The Potrerillos minibasin of the La Popa basin, Mexico, is defined by the Carroza syncline and bounded by the El Gordo anticline and the La Popa salt weld. Stratigraphic geometries and facies distribution of the upper sandstone member of the Potrerillos Formation within the minibasin indicate that diapirism, shortening, and deposition were simultaneous and complexly interrelated during the Paleocene. The upper sandstone member is a regressive succession of marginal marine, siliciclastic deposits. Wave-dominated shoreface deposits consist of mudstone, siltstone, and sandstone and are interpreted to represent offshore to upper shoreface environments. Tide-dominated environments are heterogeneous and grouped into four broad classes based on the energy of the depositional environment. Lower delta-plain deposits range from mudstone to sandstone and are interpreted to represent channel, flood-plain, and lagoonal environments. Sedimentary structure orientations indicate asymmetrical, bidirectional paleocurrents with a dominant southeast trend parallel to regional structural trends. Unconformity-bounded strata onlap the El Gordo anticline, indicating syndepositional folding and control of the depositional system by detachment fold trends in the basin. The strata of the upper sandstone member are interpreted to contain six systems tracts that record three successive fourth-order eustatic cycles. These strata represent the deposits of a prograding, ebb-dominated deltaic system confined to the Carroza syncline. Maximum stratal accumulation in the synclinal hinge caused the migration of underlying salt into flanking structures. A balance between salt withdrawal and subsidence stabilized the position of both the synclinal hinge and the shoreline, leading to a positive deposition-subsidence feedback loop. During regional regression, the structural basin defined by the syncline formed a paleogeographic embayment and controlled shoreline evolution.

Clifton, H. E. and R. L. Phillips (1980). "Stratification Types in Inter-Tidal Sediment, Willapa Bay, Washington." Aapg Bulletin-American Association of Petroleum Geologists 64(5): 692-692.

Clifton, H. E., R. L. Phillips, et al. (1976). "Modern and Ancient Estuarine-Fill Facies, Willapa Bay, Washington." Aapg Bulletin-American Association of Petroleum Geologists 60(4): 657-658.

Phillips, R. L., H. E. Clifton, et al. (1976). "Bed Forms and Internal Structures in Deep Estuary Channel System, Willapa Bay, Washington." Aapg Bulletin-American Association of Petroleum Geologists 60(4): 708-708.

Felsot, A. S. and J. R. Ruppert (2000). "Imidacloprid concentrations in Willapa Bay (Washington) water and sediment following application for control of burrowing shrimp." Abstracts of Papers of the American Chemical Society 220: U68-U68.

Wang, Q., S. Q. An, et al. (2006). "Invasive Spartina alterniflora: biology, ecology and management." Acta Phytotaxonomica Sinica 44(5): 559-588.

Smooth cordgrass Spartina alterniflora Loisel., a perennial rhizomatous grass native to the Atlantic and Gulf coasts of North America, spreads rapidly in estuaries and coastal salt marshes in the Pacific coast of North America, Europe, New Zealand and China, and has caused considerable effects on the invaded regions. We here describe a comprehensive account of its biology and ecology, and discuss the management of this invasive plant. S. alterniflora was intentionally introduced to China in 1979 for the purposes of erosion check, soil melioration and dike protection. However, its rapid elongation rates, high leaf area indices, high photosynthetic rates, long photosynthetic season and clonal growth make S. alterniflora an aggressive competitor with native salt marsh plants in the coastal regions in China. The estimates made for the year 2002 show that S. alterniflora covered 112000 hectares throughout the eastern China, from Guangxi (21 degrees N) to Tianjin (39 degrees N), and is still spreading rapidly in the east coast of China. The successful invasion of S. alterniflora in non-native ranges is obviously the result of the interactions between its great invading ability and a high invasibility of the invaded ecosystems, which is further facilitated by human activities. On the basis of its population trend and potential impact on native ecosystems, S. alterniflora was officially placed on the list of most harmful invasive alien plants (nine species) in China in 2003. S. alterniflora invasions in the salt marshes have multiple effects on the abiotic and biotic properties and the functioning of the invaded ecosystems, including conversion of mudflats to Spartina meadows, loss of shorebirds' foraging habitats, alteration of ecosystem processes (e.g. carbon and nitrogen cycling), decrease in abundance of native species, degradation-of native ecosystems and their functions, and considerable economic loss. It is predicted that the environmental changes driven by human activities in the coastal regions (e.g. eutrophication, sea level rise and saltwater intrusion) may favour its further invasions in coastal ecosystems in the future. Like other invasive species, it is quite difficult, expensive and even impossible to eradicate S. alterniflora once it has successfully invaded the coastal ecosystems. Obviously, further intentional introductions of S. alterniflora should be banned in China, and effective control measures should be urgently taken, to minimize the negative impacts of S. alterniflora on native ecosystems in China.

Daehler, C. C. and D. R. Strong (1994). "Variable Reproductive Output among Clones of Spartina-Alterniflora (Poaceae) Invading San-Francisco Bay, California - the Influence of Herbivory, Pollination, and Establishment Site." American Journal of Botany 81(3): 307-313.

Spartina alterniflora has recently been introduced to San Francisco Bay, California, and is rapidly invading open mud flats, growing in circular patches that we found to be individual genetic clones. We collected spikelet samples from more than 200 clones and observed germination rates ranging from O% to 59%, indicating substantial variation in reproductive output among clones. Several experiments were performed to explore the cause of variation. Pollination manipulations showed that S. alterniflora is outcrossing, but pollen supplements did not increase spikelet germination rates. Exclusion of the only insect herbivore (a phloem feeder, Prokelisia marginata) from developing inflorescences increased the proportion of spikelets containing seed, but failed to increase germinations per spikelet. Spikelets from Willapa Bay, Washington, grown free of insect herbivores, had germination rates similar to San Francisco Bay. These results suggest herbivory is not limiting reproductive output of S. alterniflora. Spikelet viability was not related to clone size; however, clones located lower in the intertidal or far up a drainage slough averaged fewer germinations per spikelet, suggesting clones in areas with lower genet density may have lower spikelet viabilities. Spikelet samples from different sections of clones growing across wide environmental ranges had similar rates of germination, suggesting some genetic influence on spikelet viability. Differential reproductive output among clones and the novel selective environment of San Francisco Bay are expected to cause gene frequency changes in this rapidly expanding population.

Wilson, A. G., J. H. Larsen, et al. (1995). "Distribution of Vandyke Salamander (Plethodon-Vandykei Vandenburgh)." American Midland Naturalist 134(2): 388-393.

Literature and field surveys were conducted to document occurrence of Van Dyke's Salamander (Plethodon vandyke) in Washington State. A map comparing the salamander's distribution with climatic and geologic variables was constructed to reveal potentially inhabited regions. At least 80 localities for the species are presently known. These occupy regions with >150 cm average annual precipitation, and have an upper altitudinal limit coinciding with the boundary between temperate mesophytic and subalpine forests. Disjunct population centers in the Willapa Hills, on the Olympic Peninsula, and in the southern Cascade Ranges are separated by glacial and alluvial deposits which appear to limit the salamander's regional distribution.

Kaysner, C. A., C. Abeyta, et al. (1990). "Incidence of Urea-Hydrolyzing Vibrio-Parahaemolyticus in Willapa Bay, Washington." Applied and Environmental Microbiology 56(4): 904-907.

Dumbauld, B. R., S. Booth, et al. (2006). "An integrated pest management program for burrowing shrimp control in oyster aquaculture." Aquaculture 261(3): 976-992.

Integrated pest management is widely applied in terrestrial agriculture, but less so in aquaculture. Parallels to insect control in agricultural fields were exploited in this application of integrated pest management principles to control burrowing shrimp Neotrypaea californiensis and Upogebia pugettensis in Pacific Northwest U.S.A. oyster aquaculture. The pesticide carbaryl has been applied to oyster aquaculture tracts to control burrowing shrimp in Washington state coastal estuaries for over 40 years. Infestations of these shrimp reduce the stability of the bottom substrate where oysters are raised and cause them to be covered with sediment and die. The use of carbaryl to control these shrimp continues to receive scrutiny despite substantial evidence that there are few if any long term environmental impacts, and the industry recently agreed to limit this practice and implement integrated pest management. The efficacy of the current control program was investigated and a monitoring plan which achieves level I goals of an integrated pest management program is described. While the pesticide was found to be 84-96% effective at removing shrimp from a given bed, new individuals can recruit back to these beds as post-larvae on an annual basis. Shrimp recruitment was low during the years of this study (1999-2002), and most monitored beds remained relatively shrimp free after treatment compared to previous records from the early 1990's when shrimp recruited more frequently and higher burrow densities were recorded on oyster beds. Some monitored beds were re-treated with pesticide during this study under the guidelines of the current pesticide application program (threshold of 10 shrimp burrows m(-2)). An attempt to experimentally define a true injury threshold as the basis of an economic action threshold for pesticide treatment, indicated that shrimp cause substantial oyster losses at levels exceeding 20 to 40 shrimp burrows m(-2). Further refinements seem unlikely given the perennial nature of this crop and a multitude of market and environmental variables affecting both crop and pest. Instead, we propose the use of an empirical decision tree in conjunction with a shrimp monitoring program to implement integrated pest management, regardless of whether the pesticide or alternative control measures are chosen as the final tool(s) for shrimp control. Published by Elsevier B.V.

Dumbauld, B. R. and S. Wyllie-Echeverria (2003). "The influence of burrowing thalassinid shrimps on the distribution of intertidal seagrasses in Willapa Bay, Washington, USA." Aquatic Botany 77(1): 27-42.

Two species of seagrasses frequently co-occur with extensive thalassinid shrimp populations and aquaculture operations in the intertidal zone of estuaries along the west coast of North America. Although thalassinid shrimp are known to be strong bioturbators and affect both aquaculture operations and benthic intertidal community structure, few studies have investigated shrimp-seagrass interactions. Application of the pesticide carbaryl to control shrimp populations for oyster aquaculture in Willapa Bay, Washington provided us with an experimental tool to investigate one such interaction. We found that the seagrass Zovera japonica colonized areas where ghost shrimp (Neotrypaea californiensis) had been removed via carbaryl application. We applied carbaryl to small (900 m(2)) experimental plots and compared seagrass colonization on these to that on control plots where shrimp remained abundant (100 m(-2)). The cumulative proportion of Z japonica seeds and sprouts was slightly higher in the surface layer of treated plots (presumably due to the lack of shrimp bioturbation distributing them to depth), but seedling abundance was not significantly different between treated (no shrimp) and untreated control plots when they first emerged in early spring. As the season progressed however, and shrimp became more active, fewer seedlings survived in the untreated areas, and those that did survive grew much more slowly than those in the treated plots. We suspect that this was due to the effects of shrimp bioturbation and either light limitation (shoots that survived were much smaller) or direct burial and loss. Although it is an introduced plant, the natural distribution of Z japonica is high in the intertidal zone and it is often separated from its congener Zostera marina by an expansive sandflat that is dominated by the ghost shrimp N. californiensis in west coast estuaries. The treatment of intertidal oysterbeds with carbaryl clearly reduces abundance of shrimp in this zone and we documented the same pattern of seagrass colonization on a commercial oyster bed and lack of seagrass in an adjacent unsprayed area. Density of native seagrass Z. marina shoots was also enhanced in plots treated with carbaryl, but only at lower tidal elevations or in intertidal pools where it could survive. We believe the removal of shrimp will continue to broaden the distribution of Z japonica in Washington coastal estuaries where carbaryl use is permitted and add an interesting perspective to this controversial management issue. (C) 2003 Elsevier B.V. All rights reserved.

Berkenbusch, K. and A. A. Rowden (2007). "An examination of the spatial and temporal generality of the influence of ecosystem engineers on the composition of associated assemblages." Aquatic Ecology 41(1): 129-147.

The present study evaluated the generality of ecosystem engineering processes by examining the influence of sympatric burrowing shrimps (Callianassidae) and intertidal seagrasses (Zosteraceae) on benthic assemblage composition in two temperate regions, south-eastern New Zealand and north-western U.S.A. In each region, intertidal macrofauna assemblage composition was determined at sites of different burrowing shrimp/seagrass density and where both species co-occured, in three different size estuaries/tidal inlets, on two occasions. Results from both regions showed that the presence of shrimps and seagrasses consistently influenced the composition of the associated infaunal assemblages at all sites, in both summer and winter. Macrofauna assemblages at shrimp sites were significantly different to those at seagrass-only and mixed sites, whereas the composition of the latter sites was similar. The differences observed between sites were best explained by sediment variables. In New Zealand, % fines and seagrass debris showed the highest correlation to differences in assemblage composition, and in the U.S.A. % fines, % carbon and sediment turnover (by shrimp) appeared to be the most important environmental parameters measured. Four to six taxa exhibited the greatest discriminating significance (including corophiid amphipods, spionid polychaetes and oligochaetes) for dissimilarities in assemblage composition observed at the different sites, with generally lower abundances at shrimp than at seagrass sites. The present study highlights the functional importance of seagrasses and bioturbating shrimps as ecosystem engineers in soft-sediment environments, and reveals the generality of their influence on associated macro-invertebrate assemblages. The findings also allow for further development of a heuristic model for ecosystem engineering by shrimp and seagrass which indicate that numerical models that aim to explore the relationship between ecosystem engineer populations and habitat modification should be expanded to capture the interaction of co-occurring engineers and be both spatially and temporally explicit.

Kilbride, K. M. and F. L. Paveglio (2001). "Long-term fate of glyphosate associated with repeated rodeo applications to control smooth cordgrass (Spartina alterniflora) in Willapa Bay, Washington." Archives of Environmental Contamination and Toxicology 40(2): 179-183.

Cordgrasses (Spartina sp.) are exotic, invasive species that threaten to degrade the intertidal zones of estuaries along the West Coast of North America. Integrated pest management (IPM) strategies primarily focus on the use of aerial and ground applications of Rodeo(R) in conjunction with mowing, but IPM treatments over multiple years usually are necessary to control Spartina. Although information exists regarding the short-term fate and effects to marine biota of a single Rodeo(R) application to control Spartina, little information is available regarding the fate and biotic effects associated with repeated Rodeo(R) applications necessary for control. Consequently, we conducted a 3-year study to assess the short- and long-term fate and potential effects to marine biota associated with repeated applications of Rodeo(R) to control smooth cordgrass in a southwestern Washington estuary. At each of three intertidal locations in Willapa Bay, we established plots on exposed mudftats and along the edge of a Spartina meadow that were hand sprayed with Rodeo(R) (5% solution) and LI-700(R) (2% solution) during July 1997 and 1998. Glyphosate concentrations in sediment from mudflat plots declined 88% to 96% from 1 day posttreatment in 1997 to 1 year after the second Rodeo applications in 1999. In contrast, glyphosate concentrations in Spartina plots increased 231% to 591% from 1997 to 1999 because Spartina rhizomes likely did not readily metabolize or exude it. Comparison of concentrations from mudflat and Spartina plots with toxicity test values for marine biota indicates that under worst-case conditions short- and long-term detrimental effects to aquatic biota from repeated application of Rodeo(R) for Spartina control would be highly unlikely.

Waitt, R. B. (1977). "Evolution of Glaciated Topography of Upper Skagit Drainage Basin, Washington." Arctic and Alpine Research 9(2): 183-192.

Davis, H. G., D. Garcia-Rossi, et al. (2002). "The use of molecular assays to identify plant pathogenic organisms vectored by biological control agents." Biocontrol 47(5): 487-497.

The planthopper Prokelisia marginata Van Duzee (Homoptera: Delphacidae) has been considered for the biological control of the weed Spartina alterniflora Loisel (Poaceae) in Willapa Bay, Washington, U.S.A. Prokelisia marginata is a stenophagous phloem-feeding insect with the potential to transmit bacterial plant diseases that could be moved by less-specific vectors to other plant species. Initial assays with PCR primers that are putatively specific for phytoplasmas gave positive results in Spartina. However, subsequent analyses did not indicate the transmission of the pathogen by the planthopper. We sequenced the 16S ribosomal RNA (rRNA) gene of the bacterial species that gave positive results in PCR. Comparisons with sequences available in GenBank suggested that the positive results using the putatively specific PCR primers were due to the presence of such bacteria as Pseudomonas, Holomonas, Vibrio, and Acinetobacter. We did not find phytoplasmas in either Spartina or the planthopper P. marginata.

Fisher, A. J., J. M. DiTomaso, et al. (2005). "Intraspecific groups of Claviceps purpurea associated with grass species in Willapa Bay, Washington, and the prospects for biological control of invasive Spartina alterniflora." Biological Control 34(2): 170-179.

Spartina alterniflora is a salt marsh halophyte introduced to the Pacific Coast of the United States that has become a noxious weed in Willapa Bay, Washington. A sap-feeding insect has been released as part of a biological control program, which has established at multiple sites. A useful complement to this program would be a biological agent that attacks seed, to reduce expansion of the infestation by seedling recruitment. One possibility is the floral-infecting, fungal pathogen Claviceps purpurea, which causes the ergot disease. This species is comprised of three intraspecific groups, of which one is specific to salt marsh habitats, G3. Based on random amplified polymorphic DNA markers, all three intraspecific groups of C purpurea were found on grasses in Willapa Bay. The incidence of ergot on Spartina was very low over the three-year sampling period. Genetic diversity was low among G3 isolates, suggesting it may have been recently introduced to the region. Greenhouse tests showed S. alterniflora from Washington to be as susceptible to C purpurea as S. alterniflora from the Atlantic Coast, where ergot has reached epidemic levels. Neighbor-joining analysis of amplified fragment length polymorphism markers suggests that G3 C purpurea in Washington is most closely related to South-eastern USA G3 C. purpurea. Pairwise comparisons as part of AMOVA showed that Willapa Bay isolates are different from those of all other geographic regions except Argentina. The low intensity of disease in Washington may be due, in part, to a G3 ergot population that is not well adapted to conditions in this area. (c) 2005 Elsevier Inc. All rights reserved.

Grevstad, F. S., D. R. Strong, et al. (2003). "Biological control of Spartina alterniflora in Willapa Bay, Washington using the planthopper Prokelisia marginata: agent specificity and early results." Biological Control 27(1): 32-42.

Spartina alterniflora (smooth cordgrass) is introduced and invasive in Pacific Coast estuaries of North America. Its invasion transforms unvegetated intertidal mudflats to grass-covered marshes, eliminating habitat for birds, fish, and native and cultivated shellfish that depend on the open mudflats. The delphacid planthopper Prokelisia marginata was recently introduced into Willapa Bay, Washington for biological control of this grass. Prior to its introduction, we demonstrated the narrow host range of P. marginata with no-choice tests in the greenhouse using 23 potential species of nontarget plants, including species of native and otherwise valuable grasses and cranberry, Vaccinium marcrocarpon. P. marginata was capable of completing its life cycle only on S. alterniflora, S. anglica (also a noxious weed in Washington State), and S. foliosa (California cordgrass, native southward from San Francisco). Based on these results, we found no evidence of risk to nontarget plants in Washington State from P. marginata. The first release of P. marginata was made in Willapa Bay in August 2000, and the planthopper survived the winter at all three sites. Following additional releases in early summer of 2001 of 65,000 individuals at each site, population densities increased an average of 4.34 +/- 1.71-fold in one generation. The populations had spread 200 in from the release area by October, 2001. Macropterous (long-winged) individuals were more common (69%) within 5 m of the release center, while brachypters (reduced-winged) were more frequent (71%) at distances greater than 5m from the release area. In field cages, P. marginata reduced S. alterniflora biomass by 50% and plant height by 15% in comparison to planthopper-free controls. These results represented short-term impacts at a localized scale. The ultimate success of this biocontrol program over wider spatial scales will only become known over a longer time period. (C) 2002 Elsevier Science (USA). All rights reserved.

Wonham, M. J. and J. T. Carlton (2005). "Trends in marine biological invasions at local and regional scales: the Northeast Pacific Ocean as a model system." Biological Invasions 7(3): 369-392.

Introduced species are an increasing agent of global change. Biogeographic comparisons of introduced biotas at regional and global scales can clarify trends in source regions, invasion pathways, sink regions, and survey effort. We identify the Northeast Pacific Ocean (NEP; northern California to British Columbia) as a model system for analyzing patterns of marine invasion success in cool temperate waters. We review literature and field surveys, documenting 123 introduced invertebrate, algal, fish, and vascular plant species in the NEP. Major invasion pathways were shipping (hull fouling, solid and water ballast; 1500s-present) and shellfish (particularly oysters) and finfish imports (commonest from the 1870s to mid-1900s). The cumulative number of successful invasions over time increased at linear, quadratic, and exponential rates for different taxa, pathways, and regions within the NEP. Regional analysis of four major NEP estuaries showed that Puget Sound and the contiguous Straits had the most introduced species, followed by Humboldt Bay, Coos Bay and Willapa Bay. Data on cumulative shipping volumes predicted smaller-scale, but not larger-scale spatial patterns in the number of shipping-mediated invasions. We identify the major challenges in scaling up from regional to global invasion analysis in cool temperate regions. Retrospective analyses for distinct biogeographic regions such as the NEP provide insight into vector dynamics and regional invasibility, and are a necessary foundation for monitoring and managing global change caused by biotic invasions.

Nelson, T. A., A. V. Nelson, et al. (2003). "Seasonal and spatial patterns of "Green tides" (Ulvoid algal blooms) and related water quality parameters in the coastal waters of Washington state, USA." Botanica Marina 46(3): 263-275.

Eutrophication-induced macroalgal blooms can impact marine communities, yet little is known about this phenomenon in the northeastern Pacific region. Changes in ulvoid biomass and water quality parameters (nutrients, transparency, temperature, salinity, and oxygen concentrations) were monitored at 6 sites on Blakely Island, Washington State, USA for two years. Observed ulvoid biomass varied from 0 to 441 g dw m(-2). Biomass peaked in summer and autumn and was greatest at sites with the highest water-column nitrogen concentrations. Intertidal ulvoid communities were dominated by Ulva fenestrata Postels et Ruprecht while Ulvaria obscura (Kutzing) Gayral dominated the subtidal zone near Blakely Island. In contrast with these observations, prior quantitative studies describe Maria as rare or ephemeral. Fifteen additional sites were examined for species composition patterns. Similar patterns were seen at sites in Puget Sound, while Enteromorpha spp. were more common and U. obscura absent at sites in Hood Canal, Willapa Bay, and Grays Harbor. Green tides and other macroalgal blooms are typically reported to be monospecific, while in the present study two or more species are in close association, albeit at different tidal elevations. Enteromorpha spp. and Ulva spp. are known as important components of green tides, but relatively little is known about the biology of Ulvaria. Substantial variation in biomass on a fine geographic scale indicates the need for fine scale monitoring of the green tide phenomenon in the northeastern Pacific region.

Hubbard, S. M., M. K. Gingras, et al. (2002). "Variability in wave-dominated estuary sandstones: implications on subsurface reservoir development." Bulletin of Canadian Petroleum Geology 50(1): 118-137.

Although ancient estuarine deposits are generally characterized by complex facies distributions, their associated sandstones commonly constitute prolific hydrocarbon reservoirs. Ebb-tidal delta, barrier-bar, tidal-inlet, flood-tidal delta, tidal-channel, tidal-flat and bayhead delta sub-environments can all be associated with sandstones that may potentially have excellent reservoir properties. Distinguishing between depositionally distinctive sandstones is crucial to the accurate reserve and deliverability assessment of reservoirs within estuarine systems. This knowledge can help plan an optimum development strategy for a hydrocarbon play. In this study, the quality and distribution of sandstones from wave-dominated estuaries is compared using subsurface data from the Lower Cretaceous Bluesky Formation of the Peace River area in Alberta. Modern sediments From Willapa Bay, Washington, are used to support observations made in the Bluesky Formation, and fill in information gaps inherent with subsurface datasets. The modern and fossil estuarine systems studied show that tidal-inlet and barrier-bar sandstones are characterized by the best reservoir qualities, followed by tidal delta, bayhead delta, tidal-channel, and lastly tidal-flat sandstones. Variability in preservation potential amongst ancient estuarine complexes can be significant, however, and is an important factor with respect to recognizing, evaluating, and ranking the economic importance of individual units from any given estuarine deposit.

Major, W. W., C. E. Grue, et al. (2003). "Concentrations of glyphosate and AMPA in sediment following operational applications of Rodeo (R) to control smooth cordgrass in Willapa Bay, Washington, USA." Bulletin of Environmental Contamination and Toxicology 71(5): 912-918.

Miller, R. B., D. L. Whitney, et al. (1993). "Tectonostratigraphic Terranes and the Metamorphic History of the Northeastern Part of the Crystalline Core of the North Cascades - Evidence from the Twisp Valley Schist." Canadian Journal of Earth Sciences 30(7): 1306-1323.

The Twisp Valley Schist (TVS) is important for both the correlation of terranes in the Cascades crystalline core and for the determination of the metamorphic pressure-temperature-time history of the northeastern part of the core. The TVS is a chaotically mixed unit of mainly siliceous schist (metachert) with significant amounts of metabasite, calc-silicate rock, and marble, and minor ultramafite and metapsammite. Geochemical analyses of metabasites indicate that the TVS contains both ocean-island basalts (OIB) and mid-ocean-ridge basalts (MORB). The TVS is lithologically similar to the Napeequa unit of the Chelan Mountains terrane in the Cascades core and is broadly correlative with units outside of the core, including the Mississippian-Jurassic Bridge River - Hozameen terrane of the eastern Coast belt, and coeval OIB-bearing terranes in the Northwest Cascades thrust system. Much of the northeastern Cascades core thus consists of oceanic rocks that probably originally lay between the Insular and the Intermontane superterranes, or were part of the latter superterrane. The TVS experienced polyphase deformation and greenschist to middle amphibolite facies metamorphism during the interval from 90 Ma (and possibly earlier) to ca. 50 Ma. Paleocene (ca. 65 - 58 Ma) dynamothermal metamorphism is the best documented event and in part resulted from forcible emplacement of plutons and from broadly distributed deformation in the Ross Lake fault zone. Major crustal loading of the TVS is inferred from the replacement of andalusite by kyanite, the presence of garnets that record an increase in pressure of 1.5-3.0 kbar (1 kbar = 100 MPa) from cores to rims, and the deeper emplacement levels of younger plutons. Loading may record thrusting in the northeastern core that is bracketed between 88 and 65 Ma and is younger than previously recognized, major contractional deformation in the North Cascades.

Bacon, C. R., P. K. Weber, et al. (2004). "Migration and rearing histories of chinook salmon (Oncorhynchus tshawytscha) determined by ion microprobe Sr isotope and Sr/Ca transects of otoliths." Canadian Journal of Fisheries and Aquatic Sciences 61(12): 2425-2439.

Strontium isotope and Sr/Ca ratios measured in situ by ion microprobe along radial transects of otoliths of juvenile chinook salmon (Oncorhynchus tshawytscha) vary between watersheds with contrasting geology. Otoliths from ocean-type chinook from Skagit River estuary, Washington, had prehatch regions with Sr-87/Sr-86 ratios of similar to0.709, suggesting a maternally inherited marine signature, extensive fresh water growth zones with Sr-87/Sr-86 ratios similar to those of the Skagit River at similar to0.705, and marine-like Sr-87/Sr-86 ratios near their edges. Otoliths from stream-type chinook from central Idaho had prehatch Sr-87/Sr-86 ratios greater than or equal to0.711, indicating that a maternal marine Sr isotopic signature is not preserved after the similar to1000- to 1400-km migration from the Pacific Ocean. Sr-87/Sr-86 ratios in the outer portions of otoliths from these Idaho juveniles were similar to those of their respective streams (similar to0.708-0.722). For Skagit juveniles, fresh water growth was marked by small decreases in otolith Sr/Ca, with increases in Sr/Ca corresponding to increases in Sr-87/Sr-86 with migration into salt water. Otoliths of Idaho fish had Sr/Ca radial variation patterns that record seasonal fluctuation in ambient water Sr/Ca ratios. The ion microprobe's ability to measure both Sr-87/Sr-86 and Sr/Ca ratios of otoliths at high spatial resolution in situ provides a new tool for studies of fish rearing and migration.

Beechie, T. J., C. M. Greene, et al. (2006). "Incorporating parameter uncertainty into evaluation of spawning habitat limitations on Chinook salmon (Oncorhynchus tshawytscha) populations." Canadian Journal of Fisheries and Aquatic Sciences 63(6): 1242-1250.

Incorporating parameter uncertainty into a Monte Carlo procedure for estimating spawning habitat capacity helped determine that spawning habitat availability is unlikely to limit recovery of six populations of Chinook salmon (Oncorhynchus tshawytscha) in Puget Sound. Spawner capacity estimates spanned up to four orders of magnitude, yet there was virtually no overlap of distributions of capacity estimates with distributions of current spawner abundance (< 0.2% overlap), except for the Suiattle River population (51% overlap). Empirical distributions of input parameters contained several important sources of uncertainty, insuring reasonably wide distributions of capacity estimates. The most defensible ranges of input parameters tended to produce conservative capacity estimates, indicating that increased model accuracy would only strengthen our conclusion that spawning habitat is not a constraint on these populations. There are insufficient data with which to develop parameter distributions that better represent historical capacity, which would certainly be higher than our estimates. Our results suggest that factors other than spawning capacity limit population size and that recovery efforts for Skagit River Chinook salmon need not focus on spawning habitat restoration.

Greene, C. M. and T. J. Beechie (2004). "Consequences of potential density-dependent mechanisms on recovery of ocean-type chinook salmon (Oncorhynchus tshawytscha)." Canadian Journal of Fisheries and Aquatic Sciences 61(4): 590-602.

Restoring salmon populations depends on our ability to predict the consequences of improving aquatic habitats used by salmon. Using a Leslie matrix model for chinook salmon (Oncorhynchus tshawytscha) that specifies transitions among spawning nests (redds), streams, tidal deltas, nearshore habitats, and the ocean, we compared the relative importance of different habitats under three density-dependent scenarios: juvenile density independence, density-dependent mortality within streams, delta, and nearshore, and density-dependent migration among streams, delta, and nearshore. Each scenario assumed density dependence during spawning. We examined how these scenarios influenced priorities for habitat restoration using a set of hypothetical watersheds whose habitat areas could be systematically varied, as well as the Duwamish and Skagit rivers. In all watersheds, the three scenarios shared high sensitivity to changes in in nearshore and ocean mortality and produced similar responses to changes in other parameters controlling mortality (i.e., habitat quality). However, the three scenarios exhibited striking variation in population response to changes in habitat area (i.e., capacity). These findings indicate that nearshore habitat relationships may play significant roles for salmon populations and that the relative importance of restoring habitat area will depend on the mechanism of density dependence influencing salmon stocks.

Warnock, N., J. Y. Takekawa, et al. (2004). "Migration and stopover strategies of individual Dunlin along the Pacific coast of North America." Canadian Journal of Zoology-Revue Canadienne De Zoologie 82(11): 1687-1697.

We radio-marked 18 Dunlin, Calidris alpina (L., 1758), at San Francisco Bay, California, and 11 Dunlin at Grays Harbor, Washington, and relocated 90% of them along the 4200 km long coastline from north of San Francisco Bay to the Yukon-Kuskokwim Delta, Alaska. The Copper River Delta, Alaska, was the single most important stopover site, with 79% of the marked birds detected there. Our second most important site was the Willapa Bay and Grays Harbor complex of wetlands in Washington. The mean length of stay past banding sites ranged from 1.0 to 3.8 days. Controlling for date of departure, birds banded at San Francisco Bay had higher rates of travel to the Copper River Delta than those banded at Grays Harbor. The later a bird left a capture site, the faster it traveled to the Copper River Delta. Length of stay at the Copper River Delta was inversely related to arrival date. We did not find any effect of sex on travel rate or length of stay. Combining the results of this study with our previous work on Western Sandpipers, Calidris mouri (Cabanis, 1875), reveals variation of migration strategies used within and among shorebird species along the eastern Pacific Flyway.

Stowel, H. H. and E. Stein (2005). "The significance of plagioclase-dominant coronas on garnet, Wenatchee Block, northern Cascades, Washington, USA." Canadian Mineralogist 43: 367-385.

Coronas on garnet, reported from numerous localities throughout the North Cascades Crystalline Core, have been interpreted to record rapid exhumation, associated with regional late Cretaceous and early Paleogene unroofing. Granodiorite dikes adjacent to tonalite and gabbro bodies, in the southern and central Cascades Core, contain fine-grained plagioclase-dominant coronas cored by garnet. Locally, these coronas were strongly deformed into ellipsoids with aspect ratios of 1:1.8:3.1. The matrix assemblage around coronas is biotite + plagioclase + quartz + ilmenite + apatite + zircon +/- allanite +/- muscovite +/- sillimanite. Garnet is strongly zoned with simple or complex patterns. Simply zoned garnet shows a core-to-rim variation: 70-81% almandine, 7-10% pyrope, 10-2% spessartine, 14-8% grossular, with no reversals in zoning near the rim (e.g., no MD increase), and is interpreted as metamorphic growth-zoning. Examples of complexly zoned garnet show core-to-rim zoning indicative of diffusive re-equilibration of central grains, and overgrowth of younger grains. Plagioclase in all samples is mostly anhedral and unzoned, but many grains include small An(60-70) cores with oscillatory zoning that are interpreted as relict phenocrysts. Plagioclase composition and texture, and phase-equilibria constraints on mineral reactions, are most compatible with garnet growth by replacement of igneous high-An plagioclase plus chlorite by "new" lower-Ca (An(40)) plagioclase and garnet. Incomplete progress of the reaction, as indicated by persistence of coronas and "relics" of primary plagioclase, may be due to an abrupt decrease in temperature, with possible loss of fluid. The textural and mineral-chemical data support the interpretation that these plagioclase-dominant coronas around garnet from the central Cascades Core developed during prograde M-3 metamorphism, after intrusion of the Mount Stuart batholith, not late decompression.

Page, G. W., L. E. Stenzel, et al. (1999). "Overview of shorebird abundance and distribution in wetlands of the Pacific Coast of the contiguous United States." Condor 101(3): 461-471.

We coordinated censuses from April 1988 to April 1995 to obtain an overview of shorebird abundance and distribution in Pacific Coast wetlands of the contiguous United States. We attempted to acquire at least 3 years of data for all major wetlands from counts within a short time window each fall, winter, and spring. Fourteen abundant, 8 moderately abundant, and 21 rare-to-uncommon species were recorded. For temperate-zone breeders, peak periods of abundance were fall or winter and, when discernible for arctic breeders, mostly fall or spring. Arctic breeders were relatively more abundant than temperate-zone breeders in Oregon and Washington wetlands. All five of the most abundant temperate breeders were limited primarily to California wetlands in all seasons. Only for Western Sandpiper (Calidris mauri) and Dunlin (C. alpina) did the estimated total individuals present simultaneously in all wetlands exceed 100,000. Fifty-six of 66 sites surveyed had at least four counts and at least 100 shorebirds on one or more counts; 38 of the 56 sites held at least 1% of 1 of 13 key species during at least one season. San Francisco Bay accounted for 24-96% of the estimated totals for key species; Grays Harbor, Willapa Bay, Humboldt Bay, Tomales Bay, Point Reyes Esteros, Bolinas Lagoon, Elkhorn Slough, Morro Bay, Mugu Lagoon, Bolsa Chica, Mission Bay, and San Diego Bay held at least 1% of at least half the key species in at least one season. The usefulness of five criteria for selecting key wetlands for shorebird conservation are examined and potential threats are discussed.

Wilson, U. W. and J. B. Atkinson (1995). "Black Brant Winter and Spring-Staging Use at 2 Washington Coastal Areas in Relation to Eelgrass Abundance." Condor 97(1): 91-98.

We monitored numbers of Black Brant (Branta bernicla nigricans) in Washington from fall 1980 through spring 1992 at Willapa Bay, and from fall 1986 through spring 1993 in the Dungeness area. We estimated brant use by converting the counts into use days. Coincidentally we also monitored variations in the extent of eelgrass (Zostera marina) beds by remote sensing techniques. At Willapa, brant use was positively correlated with the total extent of eelgrass beds and negatively correlated with the extent of oyster beds that were located within eelgrass beds, and where eelgrass had been removed by mechanical means. A 52% decline in brant use was associated with a 22% decline in eelgrass. At Dungeness there was a significant negative trend in spring-staging brant use. Overall a 63% decline in brant use coincided with a 31% decline in eelgrass. The Dungeness eelgrass beds may have declined because of natural factors. In both areas, brant use during the spring-staging period was more related to eelgrass extent than brant use during the winter months. These results suggest that Black Brant use in coastal Washington is limited by eelgrass availability. Immatures averaged 10.4% of the population at Willapa and 9.9% at Dungeness and are amongst the lowest reported. A shortage of eelgrass during the critical spring-staging period may have led to reduced endogenous reserves and associated low reproductive success of Black Brant that staged in coastal Washington, The shortage of eelgrass may have contributed to the observed southward shift to Mexico by wintering brant.

Lipow, S. R., K. Vance-Borland, et al. (2004). "Gap analysis of conserved genetic resources for forest trees." Conservation Biology 18(2): 412-423.

We developed a gap analysis approach to evaluate whether the genetic resources conserved in situ in protected areas are adequate for conifers in western Oregon and Washington (U.S.A.). We developed geographic information system layers that detail the location of protected areas and the distribution and abundance of each tree species (noble fir [Abies procera Rehd.] and Douglas-fir [Pseudotsuga menzeisii Mirb.]). Distribution and abundance were inferred from available spatial data showing modeled potential and actual vegetation. We stratified the distribution of each species into units for genetic analysis using seed and breeding zones and ecoregions. Most strata contained at least 5000 reproductive-age individuals in protected areas, indicating that genetic resources were well protected in situ throughout most of the study region. Strict in situ protection was limited, however, for noble fir in the Willapa Hills of southwestern Washington. An in situ genetic resource gap arguably occurred for Douglas-fir in the southern Puget lowlands, but this gap was filled by extensive ex situ genetic resources from the same region. The gap analysis method was an effective tool for evaluating the genetic resources of forest trees across a large region.

Rossetti, D. F. and R. G. Netto (2006). "First evidence of marine influence in the Cretaceous of the Amazonas Basin, Brazil." Cretaceous Research 27(4): 513-528.

An integrated investigation emphasizing sedimentological and ichnological studies of Cretaceous deposits of the Alter do Chao Formation, exposed in the western Amazonas Basin, was undertaken with the aim of determining depositional environments. Four facies associations attributed to upper shoreface, foreshore, delta mouth bar, and lower/middle shoreface-prodelta depositional environments were recognized. The upper shoreface deposits were deposited by storm flows. They are interbedded with highly bioturbated sandstones displaying Thalassinoides, Planolites and Diplocraterion traces. The foreshore deposits, which are coarser-grained than the shoreface strata, are characterized by tabular sandstones with planar or trough cross-lamination/stratification, wavy/flaser lamination, and parallel lamination. These strata also contain an abundance of trace fossils. The delta mouth bar deposits comprise upward-coarsening beds displaying a lobed geometry. The lower/middle shoreface-prodelta settings consist of well-stratified, very fine-grained sandstones and mudstones deposited mostly by storm wave action. A wave-dominated delta system that prograded into a marine-influenced basin is supported for the study area. Therefore, in contrast to previous interpretations, it seems that a widespread transgression during the Cretaceous would have resulted in the submergence of large continental areas in the north of Brazil, affecting sediment deposition even in the innermost portions of the intracratonic Amazonas Basin. (c) 2006 Elsevier Ltd. All rights reserved.

Peters, E. C., P. P. Yevich, et al. (1994). "Comparative Histopathology of Gonadal Neoplasms in Marine Bivalve Mollusks." Diseases of Aquatic Organisms 20(1): 59-76.

Comparative histology of gonadal neoplasms in 14 marine bivalve species or hybrids from 5 countries described in the literature and/or archived in the Registry of Tumors in Lower Animals (RTLA), Washington, DC, USA, revealed 3 basic histotypes. Hundreds of cases were of germ cell origin with different stages of development. They consisted of undifferentiated germ cells that filled individual follicles (stage 1), were present throughout the gonadal area (stage 2), or had spread to outlying tissues (stage 3). Five cases were of stromal origin. The connective tissue comprising these tumors ranged from vesicular to myxoid to spindle-cell. As these tumors grew, they invaded and destroyed normal follicles. Three cases representing a third histotype appeared to be of both germ cell and stromal origin. Two of these 3 were among 15 Crassostrea virginica recently collected from the Pawcatuck River, Rhode Island, USA. In the most advanced case, basophilic hypertrophied neoplastic germ cells were rapidly proliferating along the walls of gonadal follicles and the ducts that extended into the mantle, while the central region of the tumor mass was densely fibrous. Some neoplastic cells in follicles adjacent to normal ova-bearing follicles were differentiating into spermatocytes. Tumor cells aggressively crossed the follicular basement membrane, invaded the vesicular connective tissue supporting the gill axis, and formed a cystic mass along the luminal wall of the branchial vein. The less advanced C. virginica case had a smaller, less aggressive tumor but its basic features were similar. The third case similar in composition, pattern, and behavior was in a C. gigas that had been collected during the 1960s from the Willapa Bay, Washington, USA, and had originally been interpreted as a fibroma. All 3 of these mixed gonadal-stromal neoplasms are presently diagnosed as gonadoblastomas.

Rhodes, L. D., C. Durkin, et al. (2006). "Prevalence and analysis of Renibacterium salmoninarum infection among juvenile Chinook salmon Oncorhynchus tshawytscha in North Puget Sound." Diseases of Aquatic Organisms 71(3): 179-190.

Renibacterium salmoninarum causes bacterial kidney disease (BKD), a chronic and sometimes fatal disease of salmon and trout that could lower fitness in populations with high prevalences of infection. Prevalence of R. salmoninarum infection among juvenile Chinook salmon Oncorhynchus tshawytscha inhabiting neritic marine habitats in North Puget Sound, Washington, USA, was assessed in 2002 and 2003. Fish were collected by monthly surface trawl at 32 sites within 4 bays, and kidney infections were detected by a quantitative fluorescent antibody technique (qFAT). The sensitivity of the qFAT was within an order of magnitude of the quantitative real-time PCR (qPCR) sensitivity. Prevalence of infection was classified by fish origin (marked/hatchery vs. unmarked/likely natural spawn), month of capture, capture location and stock origin. The highest percentages of infected fish (63.5 to 63.8 %) and the greatest infection severity were observed for fish collected in Bellingham Bay. The lowest percentages were found in Skagit Bay (11.4 to 13.5 %); however, there was no difference in prevalence between marked and unmarked fish among the capture locations. The optimal logistic regression model of infection probabilities identified the capture location of Bellingham Bay as the strongest effect, and analysis of coded wire tagged (CWT) fish revealed that prevalence of infection was associated with the capture location and not with the originating stock. These results suggest that infections can occur during the early marine life stages of Chinook salmon that may be due to common reservoirs of infection or horizontal transmission among fish stocks.

Hood, W. G. (2006). "A conceptual model of depositional, rather than erosional, tidal channel development in the rapidly prograding Skagit River Delta (Washington, USA)." Earth Surface Processes and Landforms 31(14): 1824-1838.

The origin and growth of blind tidal channels is generally considered to be an erosional process. This paper describes a contrasting depositional model for blind tidal channel origin and development in the Skagit River delta, Washington, USA. Chronological sequences of historical maps and photos spanning the last century show that as sediments accumulated at the river mouth, vegetation colonization created marsh islands that splintered the river into distributaries. The marsh islands coalesced when intervening distributary channels gradually narrowed and finally closed at the upstream end to form a blind tidal channel, or at mid-length to form two blind tidal channels. Channel closure was probably often mediated through gradient reduction associated with marsh progradation and channel lengthening, coupled with large woody debris blockages. Blind tidal channel evolution from distributaries was common in the Skagit marshes from 1889 to the present, and it can account for the origin of very small modern blind tidal channels. The smallest observed distributary-derived modern blind tidal channels have mean widths of 0.3 m, at the resolution limit of the modern orthophotographs. While channel initiation and persistence are similar processes in erosional systems, they are different processes in this depositional model. Once a channel is obstructed and isolated from distributary flow, only tidal flow remains and channel persistence becomes a function of tidal prism and tidal or wind/wave erosion. In rapidly prograding like the Skagit, blind tidal channel networks are probably inherited from the antecedent distributary network. Examination of large-scale channel network geometry of such should therefore consider distributaries and blind tidal channels part of a common network and not entirely distinct elements of the system. Finally, managers of tidal restoration projects generally assume an erosional model of tidal channel development. under circumstances conducive to progradation, depositional channel development prevail instead. Copyright (c) 2006 John Wiley & Sons, Ltd.

Garcia-Rossi, D., N. Rank, et al. (2003). "Potential for self-defeating biological control? Variation in herbivore vulnerability among invasive Spartina genotypes." Ecological Applications 13(6): 1640-1649.

Invasive species can experience strong selection in their new environments. Some populations of invasive Spartina spp. cordgrass in Pacific estuaries have been separated from the specialist planthopper Prokelisia marginata for many generations while virtually no native populations, in estuaries,of the Atlantic and Gulf coasts of North America, have experienced this separation. Contemplating the implications for biological control, we compared native cordgrass populations for resistance and tolerance to the planthopper with invasive ones that have been separated from the herbivore from many generations. We found that plant genotypes varied more in their ability to resist and. support plant-hoppers in a population that had been separated from the herbivore for many generations (in Willapa Bay, Washington, USA) than in one that had be I en consistently exposed to the herbivore (in San Francisco Bay, California, USA). In the former, some plant genotypes experienced >50% shoot mortality while others experienced none. In contrast, in the latter no genotype experienced >20% shoot mortality. Population growth rates of the herbivore paralleled this pattern among plant genotypes from the two populations. Extending previous observations, we found generally lower resistance and tolerance among six (normative) cordgrass populations that have been long-separated from the planthopper than in six (native) cordgrass populations that had been consistently exposed to it. One Willapa Bay genotype of S. alterniflora was quite tolerant of the planthopper while lacking resistance; the high densities of the insect that grew on this genotype did it virtually no harm. Plant genotypes with this combination of traits are insidious to biological control. Initially they could contribute to control by fostering herbivores that harm vulnerable genotypes. However, as these tolerant plant genotypes increase in frequency, the effectiveness of biological control would decrease. Prokelisia marginata has recently been released in Willapa Bay for biological control of S. alterniflora, Our findings of tolerant but nonresistant genetic cordgrass variants suggest the need for complementary chemical and/or mechanical control of less vulnerable genotypes. Attention to the frequency and nature of genetic variation in vulnerability to natural enemies in target species is germane to both the science and the practice of biological control.

Hentschel, B. T. (1998). "Intraspecific variations in delta C-13 indicate ontogenetic diet changes in deposit-feeding polychaetes." Ecology 79(4): 1357-1370.

Many species change diets during development. Often, these ontogenetic changes are discrete and coincide with metamorphosis (e.g., amphibians), but more gradual niche changes can occur during growth. Identifying nondiscrete changes in diet and understanding their implications at the population and community levels are especially difficult for ecologists who study detritivores and other species that have poorly characterized diets. Theory and several lines of evidence suggest, however, that benthic juveniles of species that deposit feed as adults may be unable to meet their nutritional demands by deposit feeding. To reject the null hypothesis that both juveniles and adults of deposit-feeding species assimilate the same diet and to infer ontogenetic changes in diet, I used stable carbon isotopes as a natural diet tracer. I quantified body-size-dependent variations in the delta(13)C of four species of tentaculate, surface-deposit-feeding polychaetes: the ampharetid Hobsonia florida and the spionids Pseudopolydora kempi japonica, Polydora cornuta, and Pygospio elegans. In addition to worm tissues, I measured the isotopic compositions of the most likely primary producers at each field site (benthic diatoms, macroalgae, and saltmarsh grasses) to predict the worms' carbon sources. All species showed significant size-dependent variations in delta(13)C. Furthermore, populations of P. kempi japonica at two different sandflats had similar ontogenetic trends despite isotopic differences in available foods at each site. Individuals fed a fixed diet in the laboratory, however, did not show significant size-dependent variation in delta(13)C, leaving ontogenetic changes in diet as the most parsimonious explanation of the field data. Regression analyses indicated that the gradual change in delta(13)C(= with body size was nonlinear, with most of the change in delta(13)C occurring before individuals reach sexual maturity. The complex life cycle of these species, therefore, includes both a radical change in niche when larvae metamorphose to juveniles and a gradual niche shift as benthic juveniles grow. The isotopic data indicate that the smallest juveniles assimilated much of their carbon from benthic diatoms (delta(13)C approximate to -20 parts per thousand), while adults assimilated most of their carbon from detritus derived from macroalgae (delta(13)C approximate to -9 parts per thousand) or saltmarsh grasses (delta(13)C approximate to -14 parts per thousand). Because abundances of benthic diatoms or other high-quality components of sediment are more variable and more likely to be in limiting supply than detritus or bulk sedimentary organics, populations of species that deposit feed as adults may experience food-related recruitment bottlenecks during the juvenile stage.

Civille, J. C., K. Sayce, et al. (2005). "Reconstructing a century of Spartina alterniflora invasion with historical records and contemporary remote sensing." Ecoscience 12(3): 330-338.

Remote sensing is becoming a vital tool for understanding the changing vegetation patterns that are associated with broad-scale plant invasions. The establishment of North American east coast native Spartina alterniflora (smooth cordgrass) in Willapa Bay, Washington is a specific example of broad-scale invasion following local introduction. In this study, we examined a 120-y historical record of aerial photographs, oral histories, museum records, and publications to reconstruct the spatial, temporal, and historical elements of this invasion. We conclude that the most likely means for S. alterniflora to have reached Willapa Bay was the transport and translocation of oysters from New York harbour. Our data and analysis suggest that multiple areas were colonized between 1894 and 1920 coincident with sustained import of oysters from the Atlantic seaboard. We have evidence that S. alterniflora had been long established and growing in multiple widely spread locations by 1945, which is in contrast to a widely reported single introduction. Multiple foci would not only explain the colonization patterns we have observed, but could also increase the heterogeneity of the founding populations, helping to overcome barriers to reproduction that may have initially slowed the colonization in isolated populations during the first 50-70 y.

Moser, M. L. and S. T. Lindley (2007). "Use of Washington estuaries by subadult and adult green sturgeon." Environmental Biology of Fishes 79(3-4): 243-253.

Green sturgeon, Acipenser medirostris, are the most marine-oriented of North American sturgeons. However, their estuarine/marine distribution and the seasonality of estuarine use are largely unknown. We used acoustic telemetry to document the timing of green sturgeon use of Washington estuaries. In the summers of 2003 and 2004, uniquely coded acoustic transmitters were surgically implanted in green sturgeon captured using commercial gillnets. All sturgeon tagged were greater than 1.2 m total length. They were caught, tagged, and released in both Willapa Bay (n = 49) and Columbia River (n = 11) estuaries. We deployed an array of four fixedsite acoustic receivers in Willapa Bay to detect the estuarine entry and exit of these and any of over 100 additional green sturgeon tagged in other systems during 2003 and 2004. Green sturestuarine water temperatures exceeded coastal water temperatures by at least 2'C. They exhibited rapid and extensive intra- and inter- estuary movements and green sturgeon from all known spawning populations were detected in Willapa Bay. We hypothesize that green sturgeon optimize their growth potential in summer by foraging in the relatively warm, saline waters of Willapa Bay and we caution that altering the quality of estuarine habitats could negatively affect this species throughout its range.

Heller, P. L. (1981). "Small Landslide Types and Controls in Glacial Deposits - Lower Skagit River Drainage, Northern Cascade Range, Washington." Environmental Geology 3(4): 221-228.

Lee, R. R. and W. P. Staub (1993). "Role of Slope Stability in Cumulative Impact Assessment of Hydropower Development - North-Cascades, Washington." Environmental Geology 21(4): 212-214.

Two environmental assessments considered the potential cumulative environmental impacts resulting from the development of eight proposed hydropower projects in the Nooksack River Basin and 11 proposed projects in the Skagit River Basin, North Cascades, Washington, respectively. While not identified as a target resource, slope stability and the alteration of sediment supply to creeks and river mainstems significantly affect other resources. The slope stability assessment emphasized the potential for cumulative impacts under disturbed conditions (e.g., road construction and timber harvesting) and a landslide-induced pipeline rupture scenario. In the case of small-scale slides, the sluicing action of ruptured pipeline water on the fresh landslide scarp was found to be capable of eroding significantly more material than the original landslide. For large-scale landslides, sluiced material was found to be a small increment of the original landslide. These results predicted that hypothetical accidental pipeline rupture by small-scale landslides may result in potential cumulative impacts for 12 of the 19 projects with pending license applications in both river basins.

Paveglio, F. L., K. M. Kilbride, et al. (1996). "Use of Rodeo(R) and X-77(R) spreader to control smooth cordgrass (Spartina alterniflora) in a southwestern Washington estuary .1. Environmental fate." Environmental Toxicology and Chemistry 15(6): 961-968.

A I-ha plot with smooth cordgrass (Spartina alterniflora) at three locations in Willapa Bay, a southwestern Washington estuary, was aerially treated with 4.7 L/ha Rodeo(R) and 0.9 L/ha X-77(R) Spreader to determine the fate of the herbicide formulation. Rates of spray deposit on filter pads placed over treated intertidal mudflats did not differ among locations for glyphosate and aminomethylphosphonic acid (AMPA); however, deposit rates for nonylphenol polyethoxylates (NPEO) did differ among locations. Glyphosate concentrations in sediment cores from treated mudflats declined 51 to 72% during 119 days posttreatment (DPT); NPEO concentrations in sediment declined (42%) between spray day and 14 DPT. The highest concentrations of glyphosate, AMPA, and NPEO in seawater were found in off-site samples collected from the leading edge of the first high tide after application. Glyphosate and AMPA concentrations in depth-integrated seawater samples declined 73 and 42%, respectively, between the first high tide immediately following application and the second high tide at 1 DPT. Glyphosate concentrations in Spartina stems from treated plots declined 91 to 99% between 1 and 28 DPT; whereas, AMPA declined (86 and >96%) during this period. Comparison of maximum concentrations for glyphosate in seawater from this study with acute toxicity values in the literature indicates that under worst-case conditions direct effects to aquatic organisms would not be likely.

Simenstad, C. A., J. R. Cordell, et al. (1996). "Use of Rodeo(R) and X-77(R) spreader to control smooth cordgrass (Spartina alterniflora) in a southwestern Washington estuary .2. Effects on benthic microflora and invertebrates." Environmental Toxicology and Chemistry 15(6): 969-978.

In August 1992, we conducted an intensive short-term (within 119 d) experiment in southern Willapa Bay, Washington, to evaluate the potential effects on mudflat benthic communities of herbicide control of smooth cordgrass, Spartina alterniflora Loisel. A mixture of glyphosate (Rodeo(R); 4.7 L ha(-1)) and an associated surfactant, alkylarylpolyoxyethylene (AAPOE, X-77(R) Spreader; 1 L ha(-1)) was applied aerially to three mudflat sites with invasive S. alterniflora. Sediment structure (grain size), edaphic microalgal biomass (chlorophyll a), and densities of benthic and epibenthic meiofauna and benthic macrofauna were sampled systematically in treated and adjacent control (untreated) plots 1 d before, immediately after, and 1, 14, 28 and 119 d after spraying. These mudflat biota showed no definitive differences in population trends that would indicate acute responses to the herbicide and surfactant applications over the 119-d duration of the experiment. Two-way ANOVA tests of differences in slope of linear regressions of mean plot microalgal biomass and invertebrate density of 19 taxa groups or species testing short-term (2 weeks) and long-term (17 weeks) trends in response to the experimental treatment tests indicated no significant (p < 0.1) treatment and only three site effects. Natural variability in the standing stocks (in the case of benthic microalgae) or densities (invertebrates) of most of the 19 indicator taxa prior to spray application was sufficiently high within and between treatment and control plots and among sites to preclude strong inferential tests of acute effects. Although differences in mudflat habitats (e.g., tidal elevation, sediment structure) inherent in the sites prior to treatment affect the power of our ability to test direct effects, there were no indications of either short- or long-term effects on the mudflat community of aerially applying this concentration of herbicide and surfactant. This study did not explicitly address either sublethal or indirect ecological effects, such as associated with an observed decrease in the exotic eelgrass Zostera japonica, which might appear as a longer-term, more subtle response by the mudflat community.

Armstrong, D. A., C. Rooper, et al. (2003). "Estuarine production of juvenile Dungeness crab (Cancer magister) and contribution to the Oregon-Washington coastal fishery." Estuaries 26(4B): 1174-1188.

Estuaries provide nursery habitat for juvenile stages of several commercial decapod crustaceans worldwide, and those in the Northeastern Pacific are viewed as providing this function for Dungeness crab, Cancer magister. It is difficult to ascertain the degree to which such estuarine production of juveniles eventually contributes to coastal adult populations and fisheries since there are no direct surveys of adult abundance. As other authors have done, we used fishery landings data to compute the long-term average contribution of 1+ juvenile crab populations reared in estuaries to future coastal fisheries. We focused on Oregon and Washington states, but grouped landings in two large geographic zones by combining fishery ports as adjacent to Large Estuarine Zones (LEZ; Grays Harbor and Willapa Bay, Washington, and both sides of the Columbia River) and Small Estuarine Zones (SEZ; all other ports in Oregon). Mortality estimates were used to reduce 1+ crab abundance to surviving legal males, and portrayed as percent of the fisheries. Trends in the SEZ indicate that an average of only about 5-7% of estuarine production adds to the coastal adult population and contributes about $0.7 million to the fishery. The contribution is 25-30% in the LEZ (but may be higher since interannual density varies up to 5 times) and is worth about $3.9 million based on present ex-vessel value. Analyses of crab distribution and density indicate that the majority of an estuarine population (50-80%) is located in lower side channels (LSC) in spring and summer where temperature is higher and prey within and on adjacent intertidal flats is high. The potential average dollar value of equivalent legal male crab produced from the juvenile population is about $180 ha(-1) in LSC (but $280 ha(-1) in Grays Harbor where long-term density is highest), and lower in other estuarine habitats ($50-100 ha(-1)). Estuarine juvenile production provides a relatively stable source of recruits to coastal adult populations, and large systems in the LEZ are important nurseries. Since direct coastal settlement of larvae does occur but is highly variable, the estuarine contribution may be especially important when physical forcing or unusual events lead to low survival of the coastal 0+ cohort. An unusually long period of very low landings in the LEZ from 1981-1987 is interpreted in light of the Mount St. Helens eruption (1980) and subsequent transport and deposition of very fine silt fractions over much of the LEZ nearshore shelf that may have adversely affected several year classes of small, early benthic phase juveniles at that time.

Borde, A. B., R. M. Thom, et al. (2003). "Geospatial habitat change analysis in Pacific Northwest Coastal estuaries." Estuaries 26(4B): 1104-1116.

We assessed historical changes in the location and amount of potential estuarine habitat in three of the four largest coastal estuaries in the United States Pacific Northwest (Grays Harbor, Willapa Bay, and Coos Bay) as part of the Pacific Northwest Coastal Ecosystem Regional Study (PNCERS). To accomplish the historical assessment, navigation charts, hydrographic survey data, maps, and published descriptions were used to gain information on the location of the shoreline, bathymetry, and vegetated habitats, which were then digitized and subjected to geospatial analysis using a geographic information system (GIS). We used present-day elevational boundaries for marshes, flats, and eelgrass meadows to help define habitat areas where they were not indicated on historical maps. The analysis showed that tidal flats have decreased in all study areas, potential eelgrass, Zostera marina L., habitat has increased in Grays Harbor and Willapa Bay and decreased slightly in Coos Bay, tidal wetland area has declined in all three coastal estuaries with increases in localized areas due to filling and sedimentation, and dramatic changes have occurred at the mouths of Grays Harbor and Willapa Bay. These data illustrate that direct physical alteration (filling and diking) has resulted in large changes to habitats. Forest practices in the watershed, as well as variation in climatic factors and oceanographic processes, may also have contributed to changes. The information provides more evidence for managing estuarine habitats in the region and employing historical templates to plan habitat restoration in the future.

Feist, B. E. and C. A. Simenstad (2000). "Expansion rates and recruitment frequency of exotic smooth cordgrass, Spartina alterniflora (Loisel), colonizing unvegetated littoral flats in Willapa Bay, Washington." Estuaries 23(2): 267-274.

We estimated lateral growth rates of nonindigenous Spartina alterniflora patches in Willapa Bay, Washington, over three intervals between 1970 and 1990, to reconstruct recruitment frequency since S. alterniflora was initially introduced c. 1890. Black and white aerial photographs (1:24,000 scale) of four representative sites where S. alterniflora has invaded were analyzed. Individual patches were digitized on a computer, and diameter and area were computed for each patch for all years and sites sampled using CAD software. Lateral growth rates of individual S. alterniflora patches increased linearly at 79.3 (+/- 1.674 SE) cm yr(-1). Back calculations of origin dates for individual patches based on mean lateral growth rates indicate that recruitment of new patches has been episodic and increasing in frequency since initial introduction. Environmental factors such as sea surface temperature, sea level, and precipitation may account for some of this recruitment variability. These data may be useful in existing and future models of S. alferniflora expansion in Pacific Northwest estuaries.

Feldman, K. L., D. A. Armstrong, et al. (2000). "Oysters, crabs, and burrowing shrimp: Review of an environmental conflict over aquatic resources and pesticide use in Washington State's (USA) coastal estuaries." Estuaries 23(2): 141-176.

Washington State's coastal estuaries are productive shallow water environments that support commercial fisheries for Dungeness crabs (Cancer magister) and English sole (Parophrys vetulus) by providing 0+ (settlement to age 1) populations with critical refuge and foraging habitats until subadults migrate to the nearshore coast. Intertidal mudflats also constitute prime areas for commercial oyster (Crassoscrea gigas) culture, an important industry for the coastal communities of Willapa Bay and Grays Harbor that supply much of the nation's oysters. Conflicts over natural resources and estuarine utilization have arisen over the last 37 yr due to the use of carbaryl (an organocarbamate pesticide) by oyster growers on their grounds to control populations of burrowing thalassinidean shrimp (Neotrypaea californiensis and Upogebia pugettensis). Burrowing shrimp, which have an indirect negative effect on oyster survival and growth through bioturbation and sediment destabilization, are killed by carbaryl, as are 0+ and subadult Dungeness crabs, 0+ English sole, and other non-target species present on the tideflats at the time of application. The pesticide is delivered at 9 kg ha(-1) directly to the mudflat as a wetable powder during low tides in July and August. Commercial crabbers and other groups who have economic, recreational, and environmental interests in the estuaries have generally opposed use of the chemical that oyster growers maintain is essential to sustain production levels. For years, government natural resource agencies that regulate the use of carbaryl lacked critical information needed to effectively manage the program. An Environmental impact Statement (EIS) and Supplemental EIS have provided much of that data and helped shape management decisions with regard to establishing carbaryl concentration rates and total allowable spray area. Additional research is needed to develop more economically and environmentally sound policies for shrimp control based on burrowing shrimp-oyster interactions on an estuarine-wide scale. In this paper we review issues pertaining to oyster culture, the use of carbaryl to control burrowing shrimp populations, and effects on non-target species, drawing upon research from published articles as well as unpublished data collected by the authors. We also discuss what is known of burrowing shrimp life history and ecology and emphasize the importance of integrating information on shrimp, such as timing of recruitment, variability in year class strength, and patterns of habitat use, into carbaryl control policies or alternative strategies that may be developed in the future. We recommend controlled experimentation be done to examine the ecological effects of delaying carbaryl application to some ghost shrimp beds until October after peak recruitment of 0+ ghost shrimp has occurred, allowing the number of hectares treated each year to vary based on fluctuations in pest population densities, and modifying the substrate by applying a dense layer of oyster shell to the mudflat (shell pavement) to reduce recruitment of ghost shrimp.

Ferraro, S. P. and F. A. Cole (2004). "Optimal benthic macrofaunal sampling protocol for detecting differences among four habitats in Willapa Bay, Washington, USA." Estuaries 27(6): 1014-1025.

As part of an effort to estimate estuarine habitat values with respect to ecological indicators of benthic macrofaunal community condition, an optimal (effective and least costly) sampling protocol (sample unit size [area X depth], sieve mesh size, and sample number [n]) was determined. The goal was to use four ecological indicators (number of species, abundance, biomass, and fish and crab prey abundance) to detect differences among four intertidal habitats in Willapa Bay, Washington, United States. The four habitats were eelgrass (Zostera marina), Atlantic cordgrass (Spartina alterniflora), mud shrimp (Upogebia pugettensis), and ghost shrimp (Neotrypaea californiensis). Four sample unit areas (0.005, 0.010, 0.015, and 0.020 m(2)), two sample unit depths (0-5 and 0-10 cm), and two sieve mesh sizes (1.0 and 0.5 mm) were evaluated. The optimal sampling protocol was defined as the least costly protocol capable of reliably (statistical power, 1 - beta greater than or equal to 0.80) detecting significant (alpha = 0.05) differences among greater than or equal to 4 of the 6 pairwise habitat contrasts by ANOVA on all four ecological indicators. The relative cost of each sampling protocol was estimated as a direct function of the sample unit size and number and the cost-in-processing-time ratios of 1 (5 cm deep): 1.7 (10 cm deep) and 1 (greater than or equal to1.0 mm macrofauna size fraction); 2.5 (greater than or equal to0.5 mm macrofauna size fraction), which were taken from previous studies. The optimal sampling protocol was 15-20, 0.01-m(2) x 5-cm deep, 0.5-mm mesh samples per habitat.

Holsman, K. K., D. A. Armstrong, et al. (2003). "The necessity for intertidal foraging by estuarine populations of subadult Dungeness crab, Cancer magister: Evidence from a bioenergetics model." Estuaries 26(4B): 1155-1173.

Complex intertidal habitats characteristic of northeastern Pacific coastal estuaries provide critical nursery environments for young-of-the-year Dungeness crab, Cancer magister, yet their role in supporting subsequent year classes remains unclear. Subadult C. magister (40-130 mm; 1+ and >1+ year classes), which reach densities as high as 4,300 crabs ha(-1) in subtidal channels during low tides, migrate during flood tides from subtidal refuges into intertidal habitats to forage. As with other brachyuran species that undertake extensive tidally-driven migrations, intertidal foraging may contribute significantly to the energy budget of subadult C. magister. In order to explore the energetic incentive for intertidal migrations by subadult crabs, we developed an ontogenetically-based bioenergetics model for crabs within Willapa Bay, Washington. The model showed that energetic demand varied spatially across the bay, with the highest average energetic demand of a population of subadult crabs (2.13 x 10(6) kJ ha(-1)) occurring in a habitat stratum termed lower side channel (LSC) and characterized by relatively little subtidal area and extensive intertidal flats. Comparison of model results with subtidal prey production revealed that the latter could not satisfy subadult C. magister energetic demands, especially in LSC where modeled crab predation depleted subtidal prey biomass within 17 simulation days. We estimate that 1 ha of subtidal crabs from LSC would minimally require an additional 1.6 ha of intertidal area to satisfy energetic demands without depleting prey biomass. Our model results support the assertion that C. magister make regular migrations to forage on productive intertidal flats, and suggest that intertidal foraging may contribute significantly to the diet of subadult crabs in coastal estuaries.

Hood, W. G. (2004). "Indirect environmental effects of dikes on estuarine tidal channels: Thinking outside of the dike for habitat restoration and monitoring." Estuaries 27(2): 273-282.

While the most obvious effects of dike construction and marsh conversion are those affecting the converted land (direct or intended effects), less immediately apparent effects also occur seaward of dikes (indirect or unintended effects). I analyzed historical photos of the Skagit River delta marshes (Washington, U.S.) and compared changes in estuarine marsh and tidal channel surface area from 1956-2000 in the Wiley Slough area of the South Fork Skagit delta, and from 1937-2000 in the North Fork delta. Dike construction in the late 1950s caused the loss of 80 ha of estuarine marsh and 6.7 ha of tidal channel landward of the Wiley Slough dikes. A greater amount of tidal channel surface area, 9.6 ha, was lost seaward of the dikes. Similar losses were observed for two smaller North Fork tidal channel systems. Tidal channels far from dikes did not show comparable changes in channel surface area. These results are consistent with hydraulic geometry theory, which predicts that diking reduces tidal Hushing in the undiked channel remnants and this results in sedimentation. Dikes may have significant seaward effects on plants and animals associated with tidal channel habitat. Another likely indirect dike effect is decreased sinuosity in a distributary channel of the South Fork Skagit River adjacent to and downstream of the Wiley Slough dikes, compared to distributary channels upstream or distant from the dikes. Loss of floodplain area to diking and marsh conversion prevents flood energy dissipation over the marsh surface. The distributary channel has responded to greater flood energy by increasing mean channel width and decreasing sinuosity. Restoration of diked areas should consider historic habitat loss seaward of dikes, as well as possible benefits to these areas from dike breaching or removal. Habitat restoration by breaching or removal of dikes should be monitored in areas directly affected by dikes, areas indirectly affected, and distinct reference areas.

Huppert, D. D., R. L. Johnson, et al. (2003). "Interactions between human communities and estuaries in the Pacific Northwest: Trends and implications for management." Estuaries 26(4B): 994-1009.

This paper explores social and economic aspects of coastal communities crucial to the management of estuaries in the Pacific Northwest. These aspects include the changing demographics and economies of coastal communities, and the public perceptions, attitudes, and values pertaining to estuarine ecosystems. Information from Willapa Bay and Grays Harbor in Washington and Tillamook, Yaquina, and Coos Bays in Oregon shows that the coastal communities are growing more slowly than the states overall, that the populations are relatively old, and that, although the local economies continue to rely on them, the extractive natural resource industries (fishing, aquaculture, agriculture, forest products) are declining in importance relative to tourism, recreation, and retirement industries. These trends suggest that human uses of the estuaries are changing in character, and altering the management problems. Coastal residents choose to live in these communities to enjoy the views and scenery, to experience rural living, to be near the ocean, and to recreate outdoors. People express coherent perceptions of risks to the estuaries, especially the threats of declining fish habitats, oil spills, shoreline development, invasive species, and logging in upland areas. Residential land values are enhanced by the presence of wetlands and forests and are diminished by the presence of hazardous waste sites. We conclude that, if recent trends in population age structure, income sources, and employment status continue, public attitudes and values will move towards stronger environmental protection. Because ecosystem management involves local public participation and collaboration, estuarine managers will be faced with both increased demands and opportunities.

Newton, J. A. and R. A. Horner (2003). "Use of phytoplankton species indicators to track the origin of phytoplankton blooms in Willapa Bay, Washington." Estuaries 26(4B): 1071-1078.

We focus on the question of whether high phytoplankton production events observed in a United States Pacific Northwest estuary consist of estuarine species blooms fueled by oceanic nutrient input or reflect offshore oceanic blooms that have advected into the estuary. Our approach is to use certain phytoplankton species as indicators associated with water mass origin, either estuarine or oceanic, to help resolve this question in Willapa Bay, Washington. We used species analysis and primary production data from 10 selected dates in May-September of 1998 and 1999, representing periods of high through low productivity. Out of 108 phytoplankton species identified from Willapa Bay, nine were selected and tested as indicators of oceanic species, six as estuarine, and two as surf zone. Our test results demonstrated the oceanic and estuarine species to be satisfactory indicators of source waters. The prevalence of these species indicators in our samples revealed that the highest primary production and the appearance of Pseudo-nitzschia spp. were associated with oceanic intrusions of phytoplankton biomass into Willapa Bay. While the largest blooms were oceanic in origin, numerous medium-sized production events were from either oceanic, surf zone, or estuarine sources, indicating a complex situation.

Roegner, G. C., D. A. Armstrong, et al. (2003). "Ocean distribution of Dungeness crab megalopae and recruitment patterns to estuaries in southern Washington State." Estuaries 26(4B): 1058-1070.

We investigated the distribution of meroplankton and water properties off southern Washington and simultaneously measured time series of larval abundance and water properties in two adjacent estuaries, Grays Harbor and Willapa Bay. The cruise period, in late May 1999, coincided with large variation in the alongshore wind stress that caused dynamic change in the position of the Columbia River plume, coastal upwelling and downwelling, and offshore phytoplankton production. In the coastal ocean, meroplankton groups responded differently to this wind event and the associated advection of water masses. Dungeness crab (Cancer magister) megalopae were largely indifferent to the wide salinity variation, and were found throughout the surveyed area in both plume and recently upwelled waters. Megalopae of kelp crab (Pugettia producta) and hermit crab (Pagurus spp.) were more abundant in upwelled water and low numbers were caught in the plume water. Barnacle cyprids appeared to track the advective transport suggesting that they may be more passively dispersed. Within the estuaries, hydrography responded rapidly and synchronously to variation in wind stress. Intrusions of both plume and newly upwelled waters were detected at estuarine sites, depending on the type of water present at the coast, indicating a tight link between the estuaries and the coastal ocean in this region. A 90-d record of C. magister megalopae abundance was made at 3 estuarine sites using light traps. The bulk of the C. magister recruitment was limited to a relatively brief period in late May through June. Within this window, megalopae occurred in distinct pulses of 3-5 d interspaced with periods of low or zero abundance. C. magister megalopae recruited to the estuaries over a wide range of wind forcing, and were transported into the estuary within varied water types. There were no periodic patterns indicative of spring-neap tidal variations in the abundance time series. Abundance was only weakly cross-correlated between the adjacent Grays Harbor and Willapa Bay estuaries, which contrasts with the more synchronous estuarine-coastal linkages measured for water properties. These results suggest the interaction of larval aggregation size in the ocean with estuary-ocean exchange processes likely controls patterns of estuarine recruitment.

Rooper, C. N., D. R. Gunderson, et al. (2003). "Patterns in use of estuarine habitat by juvenile English sole (Pleuronectes vetulus) in four Eastern North Pacific estuaries." Estuaries 26(4B): 1142-1154.

English sole (Pleuronectes vetulus) is one of a few commercially important marine fishes on the Pacific coast of North America that use estuarine areas as nurseries for juvenile stages. Trawl surveys of four United States Pacific Northwest estuaries were conducted to determine spatial patterns of juvenile English sole residence in estuaries during 1998-2000. Additional data from 1983-1988 were also analyzed. Two size classes of juvenile English sole were identified during surveys, with densities of small (Total length [TL] < 50 mm) sole ranging from 0 to 11,300 fish ha(-1) across all sites, and densities of large (TL 50-150 mm) sole ranging from 0 to 33,000 fish ha(-1) across all sites. Principal components analysis of static habitat data collected at each trawl survey site was used to define habitat types within each estuary, and discriminant function analysis was used to test the resulting classification scheme. Both small and large cohort English sole used lower side channel locations at significantly higher densities than other estuarine areas. Small English sole also showed significant relationships with both bottom temperature and depth. These patterns in habitat use were consistent across all estuaries and indicate that English sole used shallow depth areas surrounded by extensive tidal flats, where temperatures were optimal for growth. The analysis also suggested a carrying capacity may exist for large English sole in nursery estuaries.

Ruesink, J. L., G. C. Roegner, et al. (2003). "Contributions of coastal and watershed energy sources to secondary production in a Northeastern Pacific estuary." Estuaries 26(4B): 1079-1093.

We examined the relationship between variation in origin of organic matter and benthic secondary production in a shallow, macrotidal estuary on the United States Pacific Northwest coast, Willapa Bay, Washington. Spatial variation in energy sources and benthic productivity were investigated at both local (vertical height and cross-bank components) and regional (sites within the bay) scales. We determined the stable carbon isotope ratios of oysters (Crassostrea gigas) to evaluate marine versus terrestrial energy sources, compared growth rates of oysters, and made time series measurements of physical variables at estuarine channel and intertidal stations. The stable carbon isotope ratios of oysters ranged from -22parts per thousand in inner portions of the estuary to -18parts per thousand near the mouth and oysters grown on the substrate surface were enriched in delta(13)C relative to those grown in the water column. These patterns are consistent with terrigenous inputs away from the estuary mouth and benthic microalgae in the diets of on-bottom oysters. The highest oyster growth was found at an inner estuary site where riverine inputs are relatively high and coincided with high ammonium in the water column. However, for most sites in Willapa Bay, oyster growth actually declined away from the estuary mouth. Reducing the time available for feeding by transplanting oysters higher in the intertidal zone had significant negative effects on growth (e.g., a reduction of 27-35% over 0.5 m). Despite the fact that oysters grown on-bottom had access to different resources than those in the water column, their growth was slower at any given tidal elevation, which may be due to on-bottom competition with other suspension feeders, boundary layer effects, or interference from turbidity. In a practical sense, oyster growers have been adjusting to allochthonous energetic support of food webs in Willapa Bay for more than a century, because they have traditionally moved oysters from southern parts of the bay where recruitment is relatively high to beds where market-size oysters can be grown closer to the mouth. This study provides mechanistic support for these practices and suggests that climatic events on a variety of temporal scales (Pacific Decadal Oscillation, upwelling events) could have economic consequences for aquaculture.

Thom, R. M., A. B. Borde, et al. (2003). "Factors influencing spatial and annual variability in eelgrass (Zostera marina L.) meadows in Willapa Bay, Washington, and Coos Bay, Oregon, estuaries." Estuaries 26(4B): 1117-1129.

Environmental factors that influence annual variability and spatial differences (within and between estuaries) in eelgrass meadows (Zostera marina L.) were examined within Willapa Bay, Washington, and Coos Bay, Oregon, over a period of 4 years (1998-2001). A suite of eelgrass metrics were recorded annually at field sites that spanned the estuarine gradient from the marine-dominated to mesohaline region of each estuary. Plant density (shoots m(-2)) of eelgrass was positively correlated with summer estuarine salinity and inversely correlated with water temperature gradients in the estuaries. Eelgrass density, biomass, and the incidence of flowering plants all increased substantially in Willapa Bay, and less so in Coos Bay, over the duration of the study. Warmer winters and cooler summers associated with the transition from El Nino to La Nina ocean conditions during the study period corresponded with this increase in eelgrass abundance and flowering. Large-scale changes in climate and nearshore ocean conditions may exert a strong regional influence on eelgrass abundance that can vary annually by as much as 700% in Willapa Bay. Lower levels of annual variability observed in Coos Bay may be due to the stronger and more direct influence of the nearshore Pacific Ocean on the Coos Bay study sites. The results suggest profound effects of climate variation on the abundance and flowering of eelgrass in Pacific Northwest coastal estuaries.

Hood, W. G. (2007). "Large woody debris influences vegetation zonation in an oligohaline tidal marsh." Estuaries and Coasts 30(3): 441-450.

The amount of large woody debris (LWD) in Pacific Northwest estuaries has declined dramatically since Euro-American settlement in the mid 19th century. Little is known about the ecological significance of estuarine LWD. This ignorance impairs protection and restoration of habitat critical to threatened Chinook salmon (Oncorhynchus tshattytscha), as well as other fish and wildlife. This study investigates whether LWD affects the distribution of estuarine shrubs, particularly nitrogen-fixing Myrica gale L. (sweetgale), which dominates the tidal shrub community of the Skagit River estuary, Washington, U.S.A. LWD, M. gale, and other shrubs were surveyed along line transects in an oligohaline tidal marsh and in abandoned agricultural land whose dikes failed more than 50 years ago and which has reverted to marsh. The results demonstrate a strong association between LWD and M. gale. M. gale was very rare on LWD < 30 cm in diameter, increasingly more common for LWD between 30 and 75 cm, and always present on LWD >= 75 cm. The marsh surface was generally 45 cm below mean higher high water (MHHW), suggesting LWD benefits M. gale by providing a growth platform at an elevation near MHHW and reducing flooding stress. The largest and most abundant tree in the marsh, Picea sitchensis, averaged only 35.8 cm in diameter, which suggests LWD recruitment from upstream sources is necessary to sustain M. gale populations in the geomorphologically dynamic Skagit marsh. By affecting the distribution and abundance of M. gale in the estuary, LWD may indirectly affect nitrogen dynamics in the marsh and secondary production of detritivores and herbivores.

Hosack, G. R., B. R. Dumbauld, et al. (2006). "Habitat associations of estuarine species: Comparisons of intertidal mudflat, seagrass (Zostera marina), and oyster (Crassostrea gigas) habitats." Estuaries and Coasts 29(6B): 1150-1160.

The complexity of habitat structure created by aquatic vegetation is an important factor determining the diversity and composition of soft-sediment coastal communities. The introduction of estuarine organisms, such as oysters or other forms of aquaculture, that compete with existing forms of habitat structure, such as seagrass, may affect the availability of important habitat refugia and foraging resources for mobile estuarine fish and decapods. Fish and invertebrate communities were compared between adjacent patches of native seagrass (Zostera marina), normative cultured oyster (Crassostrea gigas), and unvegetated mudflat within a northeastern Pacific estuary. The composition of epibenthic meiofauna and small macrofaunal organisms, including known prey of fish and decapods, was significantly related to habitat type. Densities of these epifauna were significantly higher in structured habitat compared to unstructured mudflat. Benthic invertebrate densities were highest in seagrass. Since oyster aquaculture may provide a structural substitute for seagrass being associated with increased density and altered composition of fish and decapod prey resources relative to mudflat, it was hypothesized that this habitat might also alter habitat preferences of foraging fish and decapods. The species composition of fish and decapods was more strongly related to location within the estuary than to habitat, and fish and decapod species composition responded on a larger landscape scale than invertebrate assemblages. Fish and decapod species richness and the size of ecologically and commercially important species, such as Dungeness crab (Cancer magister), English sole (Parophrys vetulus), or lingcod (Ophiodon elongatus), were not significantly related to habitat type.

McDonald, P. S., K. K. Holsman, et al. (2006). "Bioenergetics Modeling to investigate habitat use by the nonindigenous crab, Carcinus maenas, in Willapa Bay, Washington." Estuaries and Coasts 29(6B): 1132-1149.

A bioenergetics model was developed and applied to questions of habitat use and migration behavior of nonindigenous European green crab (Carcinus maenas) in Willapa Bay, Washington, USA. The model was parameterized using existing data from published studies on the ecology and physiology of C. maenas and allied brachyuran crabs. Simulations of the model were run describing four scenarios of habitat use and behavior during a 214-d simulation period (April-October) including crabs occupying mid littoral habitat, high littoral habitat, sublittoral habitat, and sublittoral habitat but undertaking intertidal migrations. Monthly trapping was done along an intertidal gradient in Willapa Bay to determine the actual distribution of crabs for the same time interval as the simulation period, and model results were compared to the observed pattern. Model estimates suggest no intrinsic energetic incentive for crabs to occupy littoral habitats since metabolic costs were c. 6% higher for these individuals than their sublittoral counterparts. Crabs in the littoral simulations were also less efficient than sublittoral crabs at converting consumed energy into growth. Monthly trapping revealed that C. maenas are found predominantly in mid littoral habitats of Willapa Bay and there is no evidence of resident sublittoral populations. The discrepancy intimates the significance of other factors, including interspecific interactions, that are not incorporated into the model but nonetheless increase metabolic demand. Agonistic encounters with native Dungeness crabs (Cancer magister) may be chief among these additional costs, and C maenas may largely avoid interactions by remaining in littoral habitats neglected by native crabs, such as meadows of nonindigenous smooth cordgrass (Spartina alterniflora). Adult C. maenas in Willapa Bay may occupy tidal elevations that minimize such encounters, and metabolic costs, while simultaneously maximizing submersion time and foraging opportunities.

Ferraro, S. P. and F. A. Cole (2007). "Benthic macrofauna-habitat associations in Willapa Bay, Washington, USA." Estuarine Coastal and Shelf Science 71(3-4): 491-507.

Estuary-wide benthic macrofauna-habitat associations in Willapa Bay, Washington, United States, were determined for 4 habitats (eelgrass [Zostera marina], Atlantic cordgrass [Spartina alterniflora], mud shrimp [Upogebia pugettensis], ghost shrimp [Neotrypaea californiensis]) in 1996 and 7 habitats (eelgrass, Atlantic cordgrass, mud shrimp, ghost shrimp, oyster [Crassostrea gigas], bare mud/sand, subtidal) in 1998. Most benthic macrofaunal species inhabited multiple habitats; however, 2 dominants, a fanworm, Manayunkia aestuarina, in Spartina, and a sand dollar, Dendraster excentricus, in subtidal, were rare or absent in all other habitats. Benthic macrofaunal Bray-Curtis similarity varied among all habitats except eelgrass and oyster. There were significant differences among habitats within- and between-years on several of the following ecological indicators: mean number of species (S), abundance (A), biomass (B), abundance of deposit (AD), suspension (AS), and facultative (AF) feeders, Swartz's index (SI), Brillouin's index (H), and jackknife estimates of habitat species richness (HSR). In the 4 habitats sampled in both years, A was about 2.5 x greater in 1996 (a La Nina year) than 1998 (a strong El Nino year) yet relative values of S, A, B, AD, AS, SI, and H among the habitats were not significantly different, indicating strong benthic macrofauna-habitat associations despite considerable climatic and environmental variability. In general, the rank order of habitats on indicators associated with high diversity and productivity (high S, A, B, SI, H, HSR) was eelgrass = oyster >= Atlantic cordgrass >= mud shrimp >= bare mud/sand >= ghost shrimp = subtidal. Vegetation, burrowing shrimp, and oyster density and sediment %silt + clay and %total organic carbon were generally poor, temporally inconsistent predictors of ecological indicator variability within habitats. The benthic macrofauna-habitat associations in this study can be used to help identify critical habitats, prioritize habitats for environmental protection, index habitat suitability, assess habitat equivalency, and as habitat value criteria in ecological risk assessments in Willapa Bay. Published by Elsevier Ltd.

Davis, H. G. (2005). "r-Selected traits in an invasive population." Evolutionary Ecology 19(3): 255-274.

I compared life-history traits and self-fertilization rates in greenhouse culture of native Spartina alterniflora with an invasive population from a low-density Pacific estuary to see whether plants in the novel r-selective regime exhibit early reproduction, greater self-compatibility and high reproductive effort putting individuals at greater risk of death. Plants were grown from seed collected from the Atlantic and Gulf coasts of North America and a population introduced approximately 100 years ago to Willapa Bay, Washington, USA that has expanded to cover over ca. 6000 hectares. Pacific marshes have almost no native emergent vascular plants in the intertidal habitat, offering a virtually empty niche for invasive S. alterniflora. The low-density plants at the leading edge of this rapidly expanding population suffer a severe Allee effect of greatly reduced fecundity, caused by pollen limitation, compared to high-density areas. I found 99% of the invasive plants initiated reproduction in the first year of this study, while only 52% of the native range plants did so in the first year, followed by 34% in the second and 14% of native plants had not initiated reproduction after three years. The invasive plants had more than twice the reproductive effort of the native plants. Plants with the highest reproductive effort in the first year of growth died regardless of coastal site of origin, although nearly all of those that died over two years were invasive Pacific plants (27%). The invaders set two times the seed as the natives under forced selfing, suggesting greater self-compatibility or reproductive effort. These results suggest either a founding and bottleneck event and/or the invasive population has evolved from the long-lived, predominantly self-incompatible, K-selected state of the probable invasive propagules originating in dense, competitive native marshes.

Miller, D. R. (1982). "Migration of a Juvenile Wolf Eel, Anarrhichthys-Ocellatus, from Port-Hardy, British-Columbia, to Willapa-Bay, Washington." Fishery Bulletin 80(3): 650-651.

Porter, R. G. (1974). "Reproductive-Cycle of Soft-Shell Clam, Mya-Arenaria, at Skagit Bay, Washington." Fishery Bulletin 72(3): 648-656.

Kvenvolden, K. A., D. J. Blunt, et al. (1979). "Amino-Acid Racemization in Quaternary Shell Deposits at Willapa Bay, Washington." Geochimica Et Cosmochimica Acta 43(9): 1505-1520.

Zorn, M. E., S. V. Lalonde, et al. (2005). "Microscale oxygen distribution in invertebrate burrows from Willapa Bay, Washington." Geochimica Et Cosmochimica Acta 69(10): A115-A115.

Baker, E. T. (1976). "Distribution, Composition, and Transport of Suspended Particulate Matter in Vicinity of Willapa Submarine Canyon, Washington." Geological Society of America Bulletin 87(4): 625-632.

Massong, T. M. and D. R. Montgomery (2000). "Influence of sediment supply, lithology, and wood debris on the distribution of bedrock and alluvial channels." Geological Society of America Bulletin 112(4): 591-599.

Field surveys in the Willapa River basin, Washington State, indicate that the drainage area-channel slope threshold describing the distribution of bedrock and alluvial channels is influenced by the underlying lithology and that local variations in sediment supply can overwhelm basinwide trends. Field data from 90 short-reach surveys indicate that about one-eighth of the surveyed reaches do not conform to a threshold defined by data from free-formed alluvial and bedrock reaches due to the effects of logjams or local sediment sources or sinks. Mapping of channel type distributions in 18 extended reconnaissance surveys of >100 channel widths in channel length show that similar to 75% of the channel network was alluvial, but that the proportion of forced alluvial channels varies from 0% to 84%, Using the drainage area-slope thresholds defined by bedrock and alluvial data from the short-reach surveys, only 40% of the total channel length mapped in the longer reconnaissance surveys was correctly classified from a 10 m grid digital elevation model. Of the misclassified reaches, 80% of the alluvial channels predicted to be bedrock had forced alluvial morphologies, while almost half of the bedrock channels predicted to be alluvial were forced by low sediment supply, typically due to their location immediately downstream of large channel-spanning logjams, Poor representation of reach-scale slope in the digital topography and/or a stochastic influence of sediment wave propagation likely account for the remaining misclassified channels, which together compose 7% of the total surveyed channel length. Although variations in sediment supply can locally overwhelm the channel type predicted by the threshold model, the effect of logjams masks any influence of propagating sediment waves on the distribution of bedrock and alluvial channels in the Willapa River basin.

Meyers, R. A., D. G. Smith, et al. (1996). "Evidence for eight great earthquake-subsidence events detected with ground-penetrating radar, Willapa barrier, Washington." Geology 24(2): 99-102.

A new approach to detect Holocene subduction-zone earthquakes combines the results from ground penetrating radar (GPR), Vibracores, and accelerator mass spectrometry (AMS) dates from a barrier spit located west of Willapa Bay, southwest Washington. GPR data show a 10-m-thick facies of beach sand within which we identify, and Vibracores confirm, beach-parallel, wave-eroded, buried scarps mantled with multiple beds of magnetite. The eight GPR-detected buried scarps are interpreted to be eroded by minor transgressions caused by instantaneous barrier subsidence during earthquakes associated with the Juan de Fuca plate subducting under the North American plate. Of these scarps, four have been AMS dated at 300, 1110, 2540, and 4250 (radiocarbon) yr B.P. No datable material has yet been found for the other four radar-detected scarps, but we interpolate and extrapolate dates of 1800, 3400, 5000, and 5800 yr B.P.

Jol, H. M., D. C. Lawton, et al. (2003). "Ground penetrating radar: 2-D and 3-D subsurface imaging of a coastal barrier spit, Long Beach, WA, USA." Geomorphology 53(1-2): 165-181.

The ability to effectively interpret and reconstruct geomorphic environments has been significantly aided by the subsurface imaging capabilities of ground penetrating radar (GPR). The GPR method, which is based on the propagation and reflection of pulsed high frequency electromagnetic energy, provides high resolution (cm to m scale) and shallow subsurface (0-60 m), near continuous profiles of many coarser-grained deposits (sediments of low electrical conductivity). This paper presents 2-D and 3D GPR results from an experiment on a regressive modem barrier spit at Willapa Bay, WA, USA. The medium-grained sand spit is 38 km long, up to 2-3.5 km wide, and is influenced by a 3.7-m tidal range (spring) as well as high energy longshore transport and high wave energy depositional processes. The spit has a freshwater aquifer recharged by rainfall. The GPR acquisition system used for the test was a portable, digital pulseEKKO(TM) system with antennae frequency ranging from 25 to 200 MHz and transmitter voltages ranging from 400 to 1000 V. Step sizes and antennae separation varied depending on the test requirements. In addition, 100-MHz antennae were used for conducting antennae orientation tests and collecting a detailed grid of data (50 x 50 m sampled every meter). The 2-D digital profiles were processed and plotted using pulseEKKO(TM)," software. The 3-D datasets, after initial processing, were entered into a LANDMARK (TM) workstation that allowed for unique 3D perspectives of the subsurface. To provide depth, near-surface velocity measurements were calculated from common midpoint (CMP) surveys. Results from the present study demonstrate higher resolution from the 200-MHz antennae for the top 5-6 m, whereas the 25- and 50-MHz antennae show deeper penetration to >10 m. For the study site, I00-MHz antennae provided acceptable resolution, continuity of reflections, and penetration. The dip profiles show a shingle-like accretionary depositional pattern, whereas strike profiles show a horizontal and subhorizontal, nearly continuous reflection pattern. Results from the GPR experiment reveal upper shoreface reflections with dip towards the ocean at about 1-2degrees. The loss of signal from below a depth of 6-8 m indicates a lithofacies change because of the storm wave base. The parallel broadside and perpendicular broadside antennae orientation tests show detailed stratigraphy, continuity, and depth of penetration. The cross-polarization test exhibits reduced continuity of reflections and less depth of penetration, but dipping reflections are apparent. The grid pattern data provided a detailed view of 3-D geometry of individual reflections. High quality data were obtained, processed, and directly exported into a LANDMARK (TM) workstation for interpretation. The resulting interpretations of the upper shoreface beds from the test cube (50 x 50 m; total 2600 traces) are shown as vertical sections (slices), horizontal sections (time slices), contour maps, 3-D representations of individual beds, and an isopach map. The 3-D depositional framework allows a more detailed interpretation than widely spaced 2-D profiles. (C) 2002 Elsevier Science B.V All rights reserved.

Costa, J. E., K. R. Spicer, et al. (2000). "Measuring stream discharge by non-contact methods: A proof-of-concept experiment." Geophysical Research Letters 27(4): 553-556.

This report describes an experiment to make a completely non-contact open-channel discharge measurement. A van-mounted, pulsed doppler (10GHz) radar collected surface-velocity data across the 183-m wide Skagit River, Washington at a USGS streamgaging station using Bragg scattering from short waves produced by turbulent boils on the surface of the river. Surface velocities were converted to mean velocities for 25 sub-sections by assuming a normal open-channel velocity profile (surface velocity times 0.85). Channel cross-sectional area was measured using a 100 MHz ground-penetrating radar antenna suspended from a cableway car over the river. Seven acoustic doppler current profiler discharge measurements and a conventional current-meter discharge :measurement were also made. Three non-contact discharge measurements completed in about a 1-hour period were within 1 % of the gaging station rating curve discharge values. With further refinements, it is thought that open-channel flow can be measured reliably by non-contact methods.

Trainer, V. L., W. P. Cochlan, et al. (2007). "Recent domoic acid closures of shellfish harvest areas in Washington State inland waterways." Harmful Algae 6(3): 449-459.

Several species of the toxigenic diatom Pseudo-nitzschia, together with low concentrations of domoic acid (DA) in shellfish have been observed in Puget Sound, Washington State, since 1991. However, for the first time in September 2003, high-density blooms of Pseudo-nitzschia forced the closure of recreational, commercial, and tribal subsistence shellfish harvesting in Puget Sound. Here we report on the environmental conditions associated with shellfish closures in two inland waterways of Washington State during the Fall 2005. In Sequim Bay, shellfish harvest losses occurred on September 12 following the measurement of elevated macronutrient levels on September 2, and a bloom of P. pseudodelicatissima (up to 13 million cells/L) on September 9. Ambient NH4 concentrations >12 mu M (measured on September 2) were likely due to anthropogenic sources, ostensibly from sewage inputs to Sequim Bay. The closure of a Penn Cove commercial shellfish farm on October 16 was caused by a bloom of P. australis that followed a period of sustained precipitation, elevated Skagit River flow, and persistent southeasterly winds. The relative importance of a number of environmental factors, including temperature, stratification caused by rivers, and nutrient inputs, whether natural or anthropogenic, must be carefully studied in order to better understand the recent appearance of massive blooms of toxigenic Pseudo-nitzschia in the inland waterways of Washington State. Published by Elsevier B.V.

Howard, J. H., L. W. Seeb, et al. (1993). "Genetic-Variation and Population Divergence in the Plethodon-Vandykei Species Group (Caudata, Plethodontidae)." Herpetologica 49(2): 238-247.

Genetic variation was investigated in the Plethodon vandykei species group by examination of 24 presumptive enzyme loci from nine populations in western Washington and the northern Rocky Mountains. Eight loci were polymorphic in at least one population. Mean heterozygosities varied from 0.00-0.04. Nei's genetic distances between populations varied from 0.00-0.37. Samples from the Olympic Mountains and Willapa Hills in western Washington were virtually identical at 24 loci. Samples from the Cascade Mountains were differentiated from the coastal Washington samples by a mean genetic distance of 0.14. Populations from the Rocky Mountains were separated from the Cascade Mountain and coastal Washington samples by mean genetic distances of 0.29 and 0.33, respectively. These data suggest long term isolation and divergence of populations in the Rocky Mountains from related forms in western Washington. Based on our analysis, we recommend recognition of the Rocky Mountain populations of this complex as Plethodon idahoensis.

Felsot, A. S. and J. R. Ruppert (2002). "Imidacloprid residues in Willapa Bay (Washington State) water and sediment following application for control of burrowing shrimp." Journal of Agricultural and Food Chemistry 50(15): 4417-4423.

Pesticides have been used in the Willapa Bay estuary in western Washington State to control the exotic invasive plant species Spartina alterniflora (cordgrass) and the native species of burrowing shrimp (Callianassa sp.; Upogebia sp.) that affect oyster production. Carbaryl, the only registered insecticide for control of burrowing shrimp, has not been extensively studied in the Willapa Bay. However, carbaryl use has been severely restricted, and alternatives likely to have less severe environmental impacts are being sought. Imidacloprid applied directly to exposed sediments when the tide is out is efficacious for burrowing shrimp control but lacks studies of its behavior in the estuary. For this study, imidacloprid dissipation was monitored as the tide was rising in Willapa Bay, Over 99% of applied material dissipated from small plots within 24 h, but residues near the analytical detection limit were found in sediments 28 days later. At a distance of 152 m along a transect from the plot in the direction of tidal flow, imidacloprid residues in water peaked within 10 min after initiation of tidal flow. Within 30 min, imidacloprid residues were not detected, nor were residues detected in the water any time over the next month after application. Carbaryl residues in water were also monitored, and they exhibited the same rise and fall at the 152 m distance from the experimental plot as did the imidacloprid residues. However, carbaryl levels significantly above the detection limit were still present in water over the next month after application. The rapid dissipation of imidacloprid from water was hypothesized to be due to extensive dilution by the tide. The hypothesis was tested in batch equilibration sorption studies with radiolabeled imidacloprid and Willapa Bay sediment. Sorption distribution coefficients were <1 mL/g, and hysteresis was not observed during two desorption cycles, suggesting that imidacloprid was widely dispersed to extremely low levels soon after application.

Hobbs, P. V. and A. L. Rangno (1978). "Reanalysis of Skagit Cloud Seeding Project." Journal of Applied Meteorology 17(11): 1661-1666.

Major, W. W., C. E. Grue, et al. (2003). "Mechanical and chemical control of smooth cordgrass in Willapa Bay, Washington." Journal of Aquatic Plant Management 41: 6-12.

We evaluated four methods to control smooth cordgrass (Spartina alterniflora Loisel), hereafter spartina, in Willapa Bay, Washington: mowing, mowing plus herbicide combination, herbicide only for clones, and aerial application of herbicide for meadows. We used a single-hand application of Rodeo(R) formulated at 480 g L-1 acid equivalence (ae) of the isopropylamine salt of glyphosate (Monsanto Agricultural Co., St. Louis, MO; currently Dow AgroSciences, Indianapolis, IN) with the non-ionic surfactant LI 7000 (2.0% v/v) on clones, and a single aerial application with X-77 Spreader(R) (0.13% v/v) on large meadows. We compared efficacy using changes in stem density and stem height I yr post-treatment. Stem densities and heights within clones were reduced by all treatments. The mowing plus herbicide combination and single-hand spray were equally more efficacious than repeated mowing at two sites, whereas at a third site, the mowing plus herbicide combination was the most efficacious. Aerial application of the herbicide resulted in an average of 91% of intended deposition, but both treatment and control plots showed similar increases in stem density and decreases in stem height. A subsequent aerial application of glyphosate with the non-ionic surfactant, R-11(R) to the study area the following year resulted in no statistically significant change in stem density on our former treated plot, but stem height decreased. However, on our former control plot, stem density significantly decreased, whereas stem height increased. We conclude that the mowing plus herbicide combination consistently provided the best control of clones, but hand application of the herbicide was almost as efficacious. The aerial herbicide applications we monitored provided little or no control indicating the need to improve efficacy if aerial treatment is to be a viable control strategy.

Major, W. W., C. E. Grue, et al. (2004). "Non-target impacts to eelgrass from treatments to control Spartina in Willapa Bay, Washington." Journal of Aquatic Plant Management 42: 11-17.

Four methods to control the smooth cordgrass Spartina (Spartina alterniflora) and the footwear worn by treatment personnel at several sites in Willapa Bay, Washington were evaluated to determine the non-target impacts to eelgrass (Zostera japonica). Clone-sized infestations of Spartina were treated by mowing or a single hand-spray application of Rodeo(R) formulated at 480 g L-1 acid equivalence (ae) of the isopropylamine salt of glyphosate (Monsanto Agricultural Co., St. Louis, MO; currently Dow AgroSciences, Indianapolis, IN) with the nonionic surfactant LI 700(R) (2% v/v) or a combination of mowing and hand spraying. An aerial application of Rodeo(R) with X-77 Spreader(R) (0.13 % v/v) to a 2-ha meadow was also investigated. Monitoring consisted of measuring eelgrass shoot densities and percent cover pre-treatment and 1-yr post-treatment. Impacts to eelgrass adjacent to treated clones were determined I m from the clones and compared to a control 5-m away. Impacts from footwear were assessed at 5 equidistant intervals along a 10-m transect on mudflat and an untreated control transect at each of the three clone treatment sites. Impacts from the aerial application were determined by comparing shoot densities and percent cover 1, 3 and 10 m from the edge of the treated Spartina meadow to that at comparable distances from an untreated meadow. Methods utilized to control Spartina clones did not impact surrounding eelgrass at two of three sites. Decreases in shoot densities observed at the third site were consistent across treatments. Most impacts to eelgrass from the footwear worn by treatment personnel were negligible and those that were significant were limited to soft mud substrate. The aerial application of the herbicide was associated with reductions in eelgrass (shoot density and percent cover) at two of the three sampling distances, but reductions on the control plot were greater. We conclude that the unchecked spread of Spartina is a far greater threat to the survival and health of eelgrass than that from any of the control measures we studied. The basis for evaluating control measures for Spartina should be efficacy and logistical constraints and not impacts to eelgrass.

Patten, K. (2003). "Persistence and non-target impact of imazapyr associated with smooth cordgrass control in an estuary." Journal of Aquatic Plant Management 41: 1-6.

The herbicide (+/--2-[4,5-dihydro-4-methyl-4-(I-methylethyl)-5-oxo-1H-imidazol-2-yl]-3 -pyridinecarboxylic acid) (imazapyr) has shown potential to control smooth cordgrass (Spartina alterniflora Loisel), a noxious weed in many estuaries throughout the world. Research was conducted under tidal estuary conditions in Willapa Bay, Washington, to determine imazapyr's persistence and aquatic risk and impact to non-target estuary species. Persistence of imazapyr in water and sediment followed an exponential decay. The maximum levels of imazapyr found in water and sediment samples after application were 3.4 mug/ml and 5.4 mug/g, respectively which are 5 to 6 orders of magnitude lower than levels needed to affect aquatic invertebrates and fish. Imazapyr in water and sediment samples approached the zero asymptote at 40 and 400 hours respectively, with half-lives of <0.5 and 1.6 days, respectively. Water collected 6 or 30 in from outside the spray zone with the first incoming tide was 99% lower than the maximum water concentration collected at the edge of the spray zone. In comparison to imazapyr applied to bare mud, an application to a smooth cordgrass canopy resulted in 75% less herbicide in the underlying sediment. The amount of imazapyr found in the interstitial water within the sediment was slightly less than that found in sediment. Japanese eelgrass (Zostera japonica Aschers and Graebn) was killed by imazapyr when it was applied to a dry canopy, but sites were reinfested within 1.0 year of treatment. Applications of imazapyr to native eelgrass (Zostera manna L.) and Japanese eelgrass covered by a thin film of tidal water had no effect. Smooth cordgrass treated with imazapyr was colonized by Japanese eelgrass and Salicornia (Salicornia virginica L.) within 12 to 20 months MAT. The osmoregulatory capacity of Chinook salmon (Oncorhynchus tshawytscha (WAL-BAUM)) smolts based on plasma sodium level and gill ATPase was not affected by imazapyr at concentrations up to 1600 mug/l. Based on these studies, imazapyr had a short half-life in estuary conditions and there was a very large margin of safety between the maximum concentration of imazapyr that occurs following application and the concentrations that could result in toxicity to invertebrates and fish. There was no direct or indirect evidence of long-term persistence or impact following its use in an estuary. It is unlikely that imazapyr used to control smooth cordgrass will pose a risk to non-target estuarine organisms.

De, C. (2005). "Quaternary ichnofacies model for paleoenvironmental and paleosealevel interpretations: a study from the Banas River Basin, western India." Journal of Asian Earth Sciences 25(2): 233-249.

Integration of data from ichnological and other interdisciplinary sources from the Quaternary Banas River Basin (India) has permitted the reconstruction of a composite ichnofacies model for the interpretation of paleoenvironments and paleosealevels. A glacioeustatic transgressive-regressive system tract of the ancient Arabian Sea has been recognized from the superposition of ichnofacies. The Pleistocene shallow marine Psilonichnus ichnofacies (ichnogenus Psilonichnus, Skolithos, Arenicolites and Thalassinoides of infaunal polychaete, crab and bivalve origin), developed in the Vadpag-Vend segment of the lower Banas sequence, corresponds to interglacial high sea stands. The overlying late Pleistocene-Holocene continental Coprinisphaera-Scoyenia mixed ichnofacies (paleosol association of delicate surficial traces of terrestrial insects and river floodplain association of aquatic traces of worms and crustaceans), formed in the Radhanpur-Varahi segment of the upper Banas sequence, represents the Last Glacial regressive mode of scalevel. Levee-bound oriented crustacean burrows may be used as new ichnological tools to locate buried paleochannels and aquifers. The juxtaposition of levees with alternate worm burrow and barren zones and floodplains with gastropod and barren zones indicates monsoonal lows and highs in the Holocene. The overprinting of the Coprinisphaera elements on the Scoyenia forms has resulted from the Recent-sub-Recent environmental degradations (rising temperature, spread of desert, shrinking saltmarshes and weakened fluvial forces) probably related to global warming and other Greenhouse processes. The readable ichnological signatures of the Quaternary glacioeustatic sealevel fluctuations and consequent climatic changes qualify the Banas model for wider application. (c) 2004 Published by Elsevier Ltd.

Callaway, J. C. (2005). "The challenge of restoring functioning salt marsh ecosystems." Journal of Coastal Research: 24-36.

Substantial improvements have been made in the restoration of coastal salt marshes over the last decade; however, many challenges remain. Some opportunities for improving restoration efforts include: I. Increasing our understanding of the development of restored salt marsh ecosystems over time, especially in comparison to natural marsh development; and identifying the limiting factors that restrict the development of restored salt marshes. If. Considering the role of plant species diversity in restored salt marshes. Recent research at Tijuana Estuary has demonstrated that there is a significant effect of plant species diversity on the development of ecosystem functions in a restored salt marsh; further study of these effects is warranted in other salt marsh ecosystems. III. Evaluating the link between physical heterogeneity and ecosystem function. Small-scale changes in physical factors, such as elevation or hydrology, are likely to have substantial effects on the development of ecosystem function in restored salt marshes, and these factors should be considered in restoration design. IV. Addressing the potential impacts of exotic plants within restored marshes. Exotic species remain a substantial problem in many restored ecosystems; better efforts are needed to identify appropriate methods to control exotic plants. V. Incorporating scientific approaches into restoration efforts. Rigorously designed scientific experiments that identify cause-effect relationships for the development of restored salt marshes could substantially improve the design, implementation, and monitoring of restoration projects.

Dumbauld, B. R., D. A. Armstrong, et al. (1996). "Life-history characteristics of two sympatric thalassinidean shrimps, Neotrypaea californiensis and Upogebia pugettensis, with implications for oyster culture." Journal of Crustacean Biology 16(4): 689-708.

An investigation of the life-history characteristics of 2 thalassinid shrimps (Neotrypaea californiensis and Upogebia pugettensis) on intertidal mud hats in Willapa Bay, Washington (U.S.A.), revealed substantial differences. Both species are viewed as pests by the oyster industry due to their ability to disturb sediments. The density of Neotrypaea was always higher than that of Upogebia in the undisturbed populations sampled, and burrow opening-shrimp density relationships differed between species (1.2 burrow openings shrimp(-1) in Neotrypaea and 1.5 openings shrimp(-1) in Upogebia). Differences were also noted in growth rate (2-3-mm CL yr(-1) for Neotrypaea versus 4-5-mm CL yr(-1) for Upogebia), size at maturity, and sexual dimorphism. Male and female claw size diverged immediately in juvenile Upogebia (4-5-mm CL, <1 yr old), but not until sexual maturation in Neotrypaea (9-10-mm CL, almost 2 yr old). Average fecundity was higher for Upogebia (7,100 eggs) than Neotrypaea (3,900 eggs) and we found a distinct difference in the seasonal reproductive cycle of the 2 species of shrimps. Neotrypaea were ovigerous from April through August and Upogebia were ovigerous from October through May. Seasonal timing of postlarval recruitment was correspondingly offset; Neotrypaea recruited to the estuary from late summer through early fall (August-October). while Upogebia recruited in spring (April-June). The seasonal difference in timing of recruitment of these shrimps to the estuary has important implications for shrimp-control programs and oyster-culture practices which are currently not being considered. Control operations occur in July before settlement of postlarvae of Neotrypaea, enabling this species to rapidly reinfest oyster-culture areas.

Davis, H. G., C. M. Taylor, et al. (2004). "An Allee effect at the front of a plant invasion: Spartina in a Pacific estuary." Journal of Ecology 92(2): 321-327.

1 Spartina alterniflora sets very little viable seed at the leading edges of an invasion in Willapa Bay, Washington, USA, where it was introduced c. 100 years ago. This largely outbreeding, rhizomatous grass recruits into previously unoccupied areas at low density, so young plants initially grow isolated from one another but eventually coalesce to form continuous meadows. 2 Isolated recruits set approximately one-tenth the seed of meadow plants at five sites, spread over the 230 km(2) of Willapa Bay mudflats, and this seed germinated at only one-third the rate observed in meadow plants. 3 The consistent patterns suggested that the low seed set in the isolated plants was largely due to the demographic effects of density. Differences between sites in the incidence and amount of seed set and germination rate indicated, however, that there was some environmental influence. 4 These data imply that plants in newly invaded, low-density areas produce little viable seed until rhizomatous growth brings them into close contact. This Allee effect could substantially reduce the rate of invasion.

Banas, N. S. and B. M. Hickey (2005). "Mapping exchange and residence time in a model of Willapa Bay, Washington, a branching, macrotidal estuary." Journal of Geophysical Research-Oceans 110(C11).

The numerical model GETM is used to examine transport pathways and residence time in Willapa Bay, Washington, a macrotidal estuary with a complex channel geometry. When the model is run with realistic forcing, it reproduces both tidal velocities and the decrease of the salt intrusion length with increasing river flow with errors of 5-20%. Furthermore, a more stringent test, when the model is run with tidal forcing only, it reproduces the along-channel profile of the effective horizontal diffusivity K, a direct measure of the strength of subtidal dispersion, which is known from previous empirical estimates. A Lagrangian, particle-tracking method is used to map subtidal transport pathways at the resolution of the model grid. This analysis reveals an interweaving of coherent lateral exchange flows with discontinuous, small-scale dispersion as well as tidal residual currents that in some locations, sharpen rather than smooth gradients between water masses. Comparison between these Lagrangian results and an Eulerian salt flux decomposition suggests that along-channel complexity (channel junctions and channel curvature) is at least as important as cross-sectional depth variation in shaping the subtidal circulation. Finally, a nonconservative tracer method is used to produce high-resolution, three-dimensional maps of residence time. This analysis shows that consistent with previous observational work in Willapa, at all except the highest winter-storm-level river flows, river- and ocean-density-driven exchanges are discernable but secondary to tidal stirring. In all seasons, despite the fact that half the volume of the bay enters and leaves with every tide, average retention times in the upper third of the estuary are 3-5 weeks.

Hickey, B. M., X. Zhang, et al. (2002). "Coupling between the California Current System and a coastal plain estuary in low riverflow conditions." Journal of Geophysical Research-Oceans 107(C10).

[1] Willapa Bay, a partially mixed coastal plain estuary, is located on the shoreward side of a narrow, deep continental shelf whose water properties fluctuate on several day scales in response to alternating periods of upwelling and downwelling. Hydrographic surveys as well as water property and velocity time series at a number of sites both within the estuary and on the adjacent coast are used to examine water property and circulation patterns in the estuary during a low runoff period. The data demonstrate that variability is significant (up to 3 psu, similar to2 degreesC and 10 cm s(-1) at 5 km from the estuary mouth) and that this variability is determined primarily by the variability in the coastal ocean rather than by estuarine processes such as changes in riverflow or neap-spring variation in mixing. Density changes near the mouth of the estuary that result from upwelling or downwelling of coastal water are consistent with transmission to the estuary primarily through a gravity current mechanism, which modifies the along-estuary density gradient and hence the gravitational circulation within the estuary. Tidal stirring is likely also important to the modification of estuary water properties. New water moves up the estuary at a rate on the order of 10 cm s(-1). Associated Eulerian residual velocity fluctuations propagate up estuary about 50% faster than water properties, indicating that up-estuary transmission of the ocean water perturbation may also have internal wave-like characteristics. The modulations in estuarine circulation and water properties lag local wind stress fluctuations (hence upwelling or downwelling) by more than a day near the estuary mouth and several days farther up the estuary.

Atwater, B. F. (1992). "Geologic Evidence for Earthquakes During the Past 2000 Years Along the Copalis River, Southern Coastal Washington." Journal of Geophysical Research-Solid Earth 97(B2): 1901-1919.

Evidence for several prehistoric earthquakes is present in deposits less than 2000 years old that crop out at the Copalis River estuary (47-degrees-07.2'N, 124-degrees-09.7'W). The deposits show that land subsided decimeters into the intertidal zone on as many as three occasions and that sand vented while the land underwent little or no subsidence on another occasion. The evidence for earthquake-induced subsidence consists of buried marsh and forest soils that evince sudden estuarine submergence attended on at least one occasion by a landward directed surge of sandy water. This combination of submergence and surge implies subsidence and tsunami. Exposed evidence for subsidence and tsunami along the Copalis River is strong for a time within a few decades of 300 years ago, moderate for a time 1400-1900 years ago, and weak (subsidence) or lacking (tsunami) for an intermediate time also about 1400-1900 years ago. The history of sudden submergence and tsunami in the past 2000 years at the Copalis River estuary resembles that shown by buried soils farther south in coastal Washington at Grays Harbor and Willapa Bay. The history can be explained most simply by great (Mw of 8 or 9) thrust earthquakes at the boundary between the Juan de Fuca and North America plates, with one or two earthquakes occurring 1400-1900 years ago and another close to 300 years ago. The evidence for earthquake-induced venting along the Copalis River consists of sand intrusions and vented-sand volcanoes. The sand rose through muddy estuarine deposits at least 3 m thick, entraining these deposits in fragments as much as 0.3 m long. Intrusion occurred at one or more times in the past 2000 years, and at least some of the venting occurred 900-1300 years ago. The sand bodies do not imply artesian flow of flood-pressured groundwater because the sand vented forcefully and infrequently through a lowland that probably lacked natural levees. The earthquake implied by the venting of sand 900-1300 years ago could have come from a source below, above, or at the boundary between the Juan de Fuca and North America plates. If from the subducted Juan de Fuca plate the implied earthquake was farther west or larger than the largest earthquakes within that plate during the past 100 years. Evidence permitting a source within the North America plate includes a fault scarp, an uplifted tideflat, and landslides near Puget Sound dating from the interval 700-1700 years ago. A plate boundary source would explain buried soils whose estuarine submergence and burial imply coseismic subsidence for parts of coastal Washington in the interval 600-1300 years ago. However, stratigraphy shows that little or no coseismic subsidence occurred along the Copalis River during the venting 900-1300 years ago. If a plate boundary earthquake struck coastal Washington 900-1300 years ago, the earthquake produced a different distribution of land level change than did the plate boundary earthquakes inferred for 1400-1900 and 300 years ago.

Valley, P. M., D. L. Whitney, et al. (2003). "Metamorphism of the deepest exposed arc rocks in the Cretaceous to Paleogene Cascades belt, Washington: evidence for large-scale vertical motion in a continental arc." Journal of Metamorphic Geology 21(2): 203-220.

The Swakane Gneiss and the overlying Napeequa Complex in the North Cascade range, Washington, were metamorphosed and deformed during development of a Cretaceous-Paleogene continental arc, and are among the structurally deepest exposed rocks within the Cordilleran arcs of North America. Peak metamorphic conditions in both the Swakane Gneiss and Napeequa Complex were c. 640-750degreesC, 9-12 kbar. Clockwise paths and widespread evidence for high-P metamorphism in meta-supracrustal rocks (burial to >40 km) document major vertical tectonic motion during arc construction and unroofing. These and other moderately high-pressure rocks in the North Cascades-Coast Mountains experienced a dramatically different tectonometamorphic history than metamorphic rocks within other Cordilleran arcs. The exhumed arc complexes of the Sierra Nevada and Peninsular Ranges are dominated by relatively low-P metamorphic and plutonic rocks (typically <6 kbar). There is no evidence that the northern Cordillera was thickened to a greater degree than these other belts, suggesting that the greater magnitude of vertical motion in the Cascades may have been related to exhumation mechanisms: Eocene extension in the northern Cordillera vs. erosional unroofing in the central and southern Cordillera.

Whitney, D. L., R. B. Miller, et al. (1999). "P-T-t evidence for mechanisms of vertical tectonic motion in a contractional orogen: north-western US and Canadian Cordillera." Journal of Metamorphic Geology 17(1): 75-90.

The > 1800 km long Coast Mountains-North Cascades orogen of the Canadian Cordillera and northwestern US developed as a continental magmatic are. Metamorphic rocks in the orogen contain widespread evidence for burial of supracrustal rocks to depths of c. 40 km, followed by nearly isothermal decompression to depths of < 10 km. Near many shallowly-emplaced, mid-Cretaceous plutons, low-pressure contact metamorphic effects were overprinted by high-pressure regional metamorphic minerals and textures, as evidenced by kyanite+/-staurolite pseudomorphs after andalusite in metapelitic rocks. Therefore, near-pluton rocks record the loading history of the orogen. Metapelitic rocks not associated with plutons only preserve evidence for high-pressure conditions and/or high-temperature decompression, as indicated, for example, by sillimanite and cordierite after kyanite and garnet, respectively. Petrological evidence for burial and decompression is therefore recorded in different rocks. Various regions of the orogen differ in timing of metamorphism, the overall shape of P-T paths and the relative timing and regional extent of the high-pressure event, but most of these data and observations are consistent with thrusting and/or pure shear thickening as primary loading mechanisms throughout the orogen, as opposed to magma-dominated loading. This interpretation is further supported by comparison with thermal models, which demonstrate that the P-T paths are consistent with simultaneous thrusting and folding at a high initial geothermal gradient (35-40 degrees C km(-1)) in much of the orogen. A high geothermal gradient supports tectonic models invoking intra-arc contraction and suggests that magmatism played an important role in regional temperature-time paths. This tectonic-thermal history may be typical of other contractional orogens and illustrates the importance of large vertical displacement of crust in magmatic arcs.

Nesbitt, E. A. and K. A. Campbell (2002). "A new Psilonichnus ichnospecies attributed to mud-shrimp Upogebia in estuarine settings." Journal of Paleontology 76(5): 892-901.

Psilonichnus lutimuratus n. ichnosp. is described from a Pliocene estuarine-mouth depositional environment (Skolithos ichnofacies) of the Olympic Peninsula, Washington, U.S.A. These simple Y-, I-, and J-shaped, mud-fined burrows occur in situ as dense patches within alternating, wavy-bedded sandstone and mudstone in a storm and flood influenced coastal sequence from an active tectonic margin. The I- and J-shaped traces represent erosional modification of burrow tops during storm-flood events. The new ichnospecies differs from the two other Psilonichnus ichnospecies by the distinct mud-lining of the burrow wall. Comparison with living thalassinoidean shrimp burrows and shrimp ecology allow this new ichnospecies to be attributed to the extant mud shrimp Upogebia. Biological and behavioral characteristics of this living shrimp restrict it to the month of the open estuary, and these parameters can be used to narrowly define a shoreline environment in the stratigraphic record.

Garcia-Casco, A., F. Haissen, et al. (2003). "Synthesis of staurolite in melting experiments of a natural metapelite: Consequences for the phase relations in low-temperature pelitic migmatites." Journal of Petrology 44(10): 1727-1757.

We document experiments on a natural metapelite in the range 650-775degreesC, 6-14 kbar, 10 wt % of added water, and 700-850degreesC, 4-10 kbar, no added water. Staurolite systematically formed in the fluid-present melting experiments above 675degreesC, but formed only sporadically in the fluid-absent melting experiments. The analysis of textures, Phase assemblages, and variation of phase composition and Fe-Mg partitioning with P and T suggests that supersolidus staurolite formed at (near-) equilibrium during fluid-present melting reactions. The experimental results me used to work out the phase relations in the system K2O-Na2O-FeO-MgO-Al2O3-SiO2-H2O appropriate for initial melting of metapelites at the upper amphibolite facies. The P-T grid developed predicts the existence of a stable P-T field for supersolidus staurolite that should be encountered by aluminous Fe-rich metapelites during fluid-present melting at relatively low temperature and intermediate pressures (675-700degreesC, 6-10 kbar for X-H2O = 1, in the KNFMASH system), but not during fluid-absent melting. The implications of these findings for the scarcity of staurolite in migmatites are discussed.

DeAmicis, S., J. Hong, et al. (2006). "Demographic similarities and differences between Zostera japonica in its native (Korea) and introduced (Willapa Bay) habitats." Journal of Phycology 42: 27-27.

Banas, N. S., B. M. Hickey, et al. (2004). "Dynamics of Willapa Bay, Washington: A highly unsteady, partially mixed estuary." Journal of Physical Oceanography 34(11): 2413-2427.

Results from 3 yr of hydrographic time series are shown for Willapa Bay, Washington, a macrotidal, partially mixed estuary whose river and ocean end members are both highly variable. Fluctuating ocean conditions-alternations between wind-driven upwelling and downwelling, and intrusions of the buoyant Columbia River plume-are shown to force order-of-magnitude changes in salinity gradients on the event (2-10 day) scale. An effective horizontal diffusivity parameterizing all up-estuary salt flux is calculated as a function of riverflow: results show that Willapa's volume-integrated salt balance is almost always far from equilibrium. At very high riverflows (the top 15% of observations) the estuary loses salt, on average, while at all other riverflow levels it gains salt. Under summer, low-riverflow conditions, in fact, the effective diffusivity K is large enough to drive a net increase in salinity that is 3-6 times the seaward, river-driven salt flux. This diffusion process is amplified, not damped, by increased tidal forcing, contrary to the expectation for baroclinic exchange. Furthermore, K varies along the length of the estuary as similar to5% of the rms tidal velocity times channel width, a scaling consistent with density-independent stirring by tidal residuals. To summarize Willapa's event- and seasonal-scale variability, a simple diagnostic parameter space for unsteady estuarine salt balances is presented, a generalization from the Hansen and Rattray steady-state scheme.

Hung, W. G., B. S. Johnson, et al. (1992). "Carrying-Capacity for Bald Eagles Wintering Along a Northwestern River." Journal of Raptor Research 26(2): 49-60.

Numbers of Bald Eagles (Haliaeetus leucocephalus) wintering along the Skagit River, Washington, in a 7-year period were correlated with estimates of numbers of Chum Salmon (Oncorhynchus keta) returning to the river to spawn, and inversely associated with daily water flows and average numbers of flood days in january and February. Available salmon biomass, measured every two weeks along 43 km of river, was in surplus of eagle requirements from 24 November 1980 through 4 January 1981, but in deficit thereafter in the same winter of close study. Recruitment of fresh Churn Salmon carcasses continued until mid-january, after which slowly receding river levels exposed additional carcasses. Coho Salmon (0. kisutch) spawning in tributaries then became a major food source. We tagged 214 live post-spawn Chum Salmon at spawning sites and we estimate from recoveries that about 13% became available to eagles. Predictions of local carrying capacity for eagles based on salmon escapement figures, the availability index of 13%, and daily food requirements of Bald Eagles showed remarkably dose fits with actual numbers of eagles supported by both the entire Skagit River drainage and an intensively studied subunit. A sample of eagles fitted with radio transmitters traveled west from the Skagit and Nooksack rivers to Puget Sound, where visual surveys showed increases in eagle numbers during january and February, corresponding with decreases on the rivers.

Clifton, H. E. (1983). "Discrimination between Subtidal and Intertidal Facies in Pleistocene Deposits, Willapa Bay, Washington." Journal of Sedimentary Petrology 53(2): 353-370.

Choi, K. S., R. W. Dalrymple, et al. (2004). "Sedimentology of modern, inclined heterolithic stratification (IHS) in the Macrotidal Han River delta, Korea." Journal of Sedimentary Research 74(5): 677-689.

An occurrence of inclined heterolithic stratification (IHS) is described from a tidal point bar in a 40-m-deep distributary of the macrotidal (tidal range 3.6-7.8 m), Han River delta, Korea. The channel bank demonstrates a convex-upward profile with intermittent presence of wave-formed scarps and terraces near the low-water level. The vertical succession of IHS is approximately 25 m thick and dips into the channel with angles reaching 14degrees. The IHS overlies 15 m of trough cross-bedded sand deposited in the channel thalweg and lower point bar. Even though the channel as a whole is ebb dominated, the preserved cross bedding is predominantly flood directed because the mutually evasive nature of the ebb and flood currents causes the point-bar surface to be flood dominated. This pattern may be a common feature of tidal point bars. The IHS itself consists of interstratified fine sand, sandy silt, and silt with an upward-fining textural trend. Tidal rhythmites are well developed in the middle and upper intertidal zone, and may also be present in the subtidal zone, but are poorly developed near the low-water level because of wave action. Seasonal discharge variations of the Han River are not obvious in the deposits, because the large size, distal location, and energetic tidal environment of the studied channel reduces the impact of river-stage fluctuations. Despite the moderate salinity levels, bioturbation is rare, except in the upper intertidal zone, because of the rapid sedimentation and energetic conditions.

Gingras, M. K., G. Pemberton, et al. (2000). "Firmness profiles associated with tidal-creek deposits: The temporal significance of Glossifungites assemblages." Journal of Sedimentary Research 70(5): 1017-1025.

Indentation tests are used to detail firmness profiles from intertidal creek deposits and wave exhumed substrates at Willapa Bay. Both of these sedimentological settings are characterized by occurrences of modern Glossifungites assemblages. Firm substrates associated with the intertidal creek deposits are derived from dewatered modern sediments, whereas firmgrounds associated with wave erosion consist of dewatered and compacted Pleistocene strata, The Pleistocene firmgrounds are notably firmer than those derived from modern deposits. A strong correlation between sediment firmness and burrowing behavior is evident in these deposits. In tidal creek systems, the comparatively firm cutbank is characterized by unlined, large-diameter, open burrows that form a Glossifungites assemblage, Intertidal point bar deposits contain a softground suite consisting of mucous-lined, small diameter, dominantly vertical traces. Finally, a softground suite of robust, mucous- or mud-lined, vertical and horizontal traces are observed in intertidal-flat deposits. In contrast, Pleistocene firmgrounds generally contain large- and small-diameter traces, with dominantly vertical architectures (Thalassinoides, Gastrochaenolites-, Diplocraterion, or Arenicolites-like burrows), depending upon the firmness of the substrate. Glossifungites occurrences on modern firmgrounds are temporally insignificant, whereas similar occurrences in Pleistocene substrates are temporally significant, Contrasting these two databases suggests that the stratigraphic significance of a Glossifungites demarcated discontinuity can be assessed in the rock record. Several criteria that are useful for identifying temporally significant surfaces are suggested, including: absence of compaction of the Glossifungites assemblage; presence of well-preserved burrow sculptings; and planar to gently undulatory erosional surfaces as opposed to surfaces with notable topographic relief. Conceptual models demonstrate that muddy substrates potentially require several millennia to compact and dewater, Sandy deposits, on the other hand, have indeterminate significance.

Gingras, M. K., M. E. Rasanen, et al. (2002). "Ichnology and sedimentology reveal depositional characteristics of bay-margin parasequences in the Miocene Amazonian foreland basin." Journal of Sedimentary Research 72(6): 871-883.

Proposed depositional models for Miocene Amazon foreland basin strata (Pebas Formation, Peru) are controversial. Recent depositional models include lacustrine and tidally influenced, brackish-water embayment. This paper presents data that support tidally influenced, brackish-water deposition for at least part of Pebas time (1014 Ma). Two parasequences are presented (Santa Julia and Tamshiyacu). Both crop out along the Amazon River in Upper Amazonia near Iquitos, Peru. At these locations, abundant evidence of brackish-water, tidally influenced deposition is documented, including marginal marine bioturbation, sedimentary couplets, semidiurnal couplets (preserved in burrows), and pinstripe lamination. The deposits are locally highly bioturbated. At both locations ichnogenera normally associated with marine to brackish-water depositional environments are common. Three normally marginal-marine ichnofabrics are reported: (1) a Chondrites-reburrowed, Planolites ichnofabric resident only in massive-appearing muds; (2) a Scolicia (Laminites), Thalassinoides, Ophiomorpha ichnofabric that is manifested as intensely bioturbated silty sands; and (3) a Thalassinoides-generated ichnofabric that is interpreted to have descended into consolidated substrates and is thus representative of the Glossifungites Ichnofacies. Several trace fossils contain laminated infills organized into distinct sedimentary couplets that are best interpreted as resulting from semidiurnal processes. Six conclusions are arrived at: (1) sedimentological and ichnological data consistently indicate that sediment accumulation dominantly occurred in sporadically dysaerobic, marine to brackish water, under a tidal influence; (2) sediment accumulation occurred in bay-margin environments that prograded into a shallow, quiescent bay; (3) a stratified water column is indicated by the ichnofauna; (4) low accommodation space, repetitive and rapid adjustments of relative sea level, shallow wave base, and a stratified water column combined to generate an atypical parasequence architecture; (5) previously published isotopic data are consistent with sediment accumulation in brackish to marine water; and (6) marine incursion into Amazonia occurred during the Middle Miocene.

Smith, D. G., R. A. Meyers, et al. (1999). "Sedimentology of an upper-mesotidal (3.7 m) Holocene barrier, Willapa Bay, SW Washington, USA." Journal of Sedimentary Research 69(6): 1290-1296.

In coastal southwest Washington, there is an unusually large (largest along the Pacific coast) and thick Holocene sand barrier 38 km long by 2.0 to 3.5 km wide by 17 to 25 m thick. The barrier is 2 to 8 times thicker than previously described Holocene barriers along the North American coast, all of which have lower-magnitude tidal regimes. The Willapa barrier is influenced by (1) a 3.7 m upper-mesotidal regime, (2) high 4-7 m Hinter storm waves, and (3) a high sediment influx da northward longshore transport in Hinter from the nearby Columbia River mouth. From the perspective of oil reservoir modeling, assuming 20% porosity and 40% recovery, the barrier has a potential reservoir of recoverable fluids of one billion barrels.

(2004). "Development and implementation of an IPM program for burrowing shrimp in Willapa Bay/Grays Harbour, Washington." Journal of Shellfish Research 23(2): 651-652.

(2004). "Implementing a monitoring program for burrowing shrimp as part of an integrated pest management program in Willapa Bay and Grays Harbor, Washington." Journal of Shellfish Research 23(2): 653-654.

(2004). "The expansion of an invasive cordgrass (Spartina alterniflora) results in the loss of critical foraging habitat for Dungeness crab (Cancer magister) in Willapa Bay, Washington." Journal of Shellfish Research 23(2): 655-655.

(2004). "Efforts of Taylor Shellfish company to alleviate the problems of burrowing shrimp on aquaculture ground in Willapa Bay, Washington." Journal of Shellfish Research 23(2): 656-656.

(2004). "The effects of different aquaculture techniques on Zostera marina biomass, density, and growth rates in Willapa Bay, Washington." Journal of Shellfish Research 23(2): 660-660.

(2005). "Eelgrass (Zostera marina) seed production and recruitment in oyster aquaculture areas in Willapa Bay, Washington." Journal of Shellfish Research 24(2): 623-623.

Dumbauld, B. R., E. P. Visser, et al. (2000). "Use of oyster shell to create habitat for juvenile Dungeness crab in Washington coastal estuaries: Status and prospects." Journal of Shellfish Research 19(1): 379-386.

The deployment of oyster shell in estuarine intertidal areas to create habitat for juvenile Dungeness crab (Cancer magister) is now used routinely as mitigation for "unavoidable losses" of crab during dredging operations in Grays Harbor and Willapa Bay along the southwest coast of Washington State. Feasibility studies were conducted in 1986 to 1987 for a U.S. Army Corps of Engineers project to widen and deepen the navigation channel in Grays Harbor. Since that lime, several studies have elucidated the ecology of crab and other organisms that recruit to the created shell reefs. Studies have also refined the procedures used to calculate crab losses caused by dredging and crab production in the shell habitat. The shell does serve as crab habitat: however, initial assumptions about the longevity of the shell have proved to be overly optimistic, because the shell can sink or be covered with silt before the end of the first summer after deployment. In addition, competition with the shore crab, Hemigrapsus oregonensis, has displaced juvenile Dungeness crab. We summarize results of these studies and present initial results from an ongoing mitigation effort that seeks to produce a more persistent living oyster reef in Willapa Bay.

Rasmussen, R. S., M. T. Morrissey, et al. (2007). "Effect of age and tissue weight on the cadmium concentration in Pacific oysters (Crassostrea gigas)." Journal of Shellfish Research 26(1): 173-179.

This study investigated the influence of age and tissue weight on cadmium (Cd) levels in Pacific oysters (Crassostrea gigas). Oysters from 4 different age groups (1, 2, 3, and 4 y) were collected at an oyster farm in Willapa Bay, Washington. To examine the effects of age, 60 oysters from each group were sorted into 3 composites of 20, and Cd analysis was carried out on all composite samples. To study the effects of tissue weights, 25 oysters from each of the 4 age groups were collected and analyzed individually for Cd. All oyster Cd concentrations were below the 3.7 ppm (mu g/g) wet wt Food and Drug Administration (FDA) level of concern and the 2 ppm wet wt Hong Kong limit. There was a moderate correlation between Cd concentration and age (R-2 = 0.60). The 1-y-old oysters had significantly lower Cd concentrations than the 2-4-y-old oysters. Tissue weight also influenced Cd concentration (R-2 = 0.31). The effect of tissue weight was found to vary with age, with a stronger correlation to Cd levels in the 1- and 2-y-olds and a weaker correlation among the 3- and 4-y-olds. The results indicate that oysters accumulate the majority of their Cd during the first two years of their lives, after which point they become saturated and show only incremental additions of Cd in later years.

Wekell, J. C., E. J. Gauglitz, et al. (1994). "The Occurrence of Domoic Acid in Razor Clams (Siliqua-Patula), Dungeness Crab (Cancer-Magister), and Anchovies (Engraulis-Mordax)." Journal of Shellfish Research 13(2): 587-593.

In September 1991, water fowl died in Monterey Bay, CA, after eating anchovies (Engraulis mordax) contaminated with domoic acid. Analysis revealed that the anchovies contained up to 485 ppm domoic acid in their viscera. This was the first reported incidence of domoic acid-related mortality of any organism in the United States. After this reported outbreak we obtained frozen samples of anchovies that were harvested near Newport, CA, in April 1991 and found they contained 270 ppm domoic acid in their viscera. By May, average domoic acid levels in frozen anchovy samples from this same area were less than 1 ppm. In October 1991, domoic acid was detected in razor clams (Siliqua patula) from Oregon and Washington and appeared to peak (an average of 106 ppm for all Washington State beaches) in the first week of December 1991. The averages then declined to less than 20 ppm without 6 months. However, domoic acid was still present at low levels (averages <5 ppm) in razor clams from Washington state beaches in December 1993. Dungeness crab (Cancer magister) in Washington and Oregon were also found to contain domoic acid, but only in their viscera. Domoic acid concentrations in the raw viscera of individual crabs from Washington state in December 1991 averaged 13 ppm and ranged from 0.8 to 90 ppm. The highest average levels of domoic acid in Washington state crabs were in the Grays Harbor and Willapa Bay samples, 32 and 31 ppm, respectively. By 1992 domoic acid level averages were <5 ppm in preseason samples of Dungeness crab taken along the Oregon and Washington coasts, ranging from 0 to 71 ppm. The highest levels of domoic acid in 1992 (36-71 ppm) were recorded in samples taken early in that year (January through April).

Gove, N. E., R. T. Edwards, et al. (2001). "Effects of scale on land use and water quality relationships: A longitudinal basin-wide perspective." Journal of the American Water Resources Association 37(6): 1721-1734.

Human land use is a major source of change in catchments in developing areas. To better anticipate the long-term effects of growth, land use planning requires estimates of how changes in land use will affect ecosystem processes and patterns across multiple scales of space and time. The complexity of biogeochemical and hydrologic interactions within a basin makes it difficult to scale up from process-based studies of individual reaches to watershed scales over multiple decades. Empirical models relating land use/land cover (LULC) to water quality can be useful in longterm planning, but require an understanding of the effects of scale on apparent land use-water quality relationships. We empirically determined how apparent relationships between water quality and LULC data change at different scales, using LULC data from the Willapa Bay watershed (Washington) and water quality data collected along the Willapa and North Rivers. Spatial scales examined ranged from the local riparian scale to total upstream catchment. The strength of the correlations between LULC data and longitudinal water quality trends varied with scale. Different water quality parameters also varied in their response to changes in scale. Intermediate scales of land use data generally were better predictors than local riparian or total catchment scales. Additional data from the stream network did not increase the strength of relationships significantly. Because of the likelihood of scale-induced artifacts, studies quantifying land use-water quality relationships performed at single scales should be viewed with great caution.

Kim, Y. O. and R. N. Palmer (1997). "Value of seasonal flow forecasts in Bayesian Stochastic Programming." Journal of Water Resources Planning and Management-Asce 123(6): 327-335.

This paper presents a Bayesian Stochastic Dynamic Programming (BSDP) model to investigate the value of seasonal flow forecasts in hydropower generation. The proposed BSDP framework generates monthly operating policies for the Skagit Hydropower System (SHS), which supplies energy to the Seattle metropolitan area. The objective function maximizes the total benefits resulting from energy produced by the SHS and its interchange with the Bonneville Power Administration. The BSDP-derived operating policies for the SHS are simulated using historical monthly inflows, as well as seasonal flow forecasts during 60 years from January 1929 through December 1988. Performance of the BSDP model is compared with alternative stochastic dynamic programming models. To illustrate the potential advantage of using the seasonal how forecasts and other hydrologic information, the sensitivity of SHS operation is evaluated by varying (1) the reservoir capacity; (2) the energy demand; and (3) the energy price. The simulation results demonstrate that including the seasonal forecasts is beneficial to SHS operation.

Smith, J. M. (2002). "Wave pressure gauge analysis with current." Journal of Waterway Port Coastal and Ocean Engineering-Asce 128(6): 271-275.

Bottom-mounted pressure gauges are used to measure waves in coastal inlets, where tidal currents are significant. Theoretically, neglect of the current in analysis of pressure data can lead to order-one errors in wave height estimates. Wave height is overestimated by neglecting flood current and underestimated by neglecting ebb current. A collocated wave buoy and bottom-mounted pressure gauge were deployed at Willapa Bay, Washington, to evaluate the significance of including current in pressure data analysis. Wave heights were overestimated by up to 20% if current was neglected. Larger current-induced errors in wave height were prevented by truncation of high-frequency energy to exclude pressure system noise. Truncation of the spectra leads to overestimates of mean wave period and underestimates of wave height. Adding a theoretical tail to the spectra reduces truncation errors. If current measurements are not available for pressure gauge analysis, reasonable results can be achieved by applying a conservative high-frequency cutoff and adding a theoretical tail.

Dunwiddie, P. W. and R. C. Kuntz (2001). "Long-term trends of bald eagles in winter on the Skagit River, Washington." Journal of Wildlife Management 65(2): 290-299.

We present a long-term assessment of a bald eagle (Haliaeetus leucocephalus) population from a wintering site in the U.S. Pacific Northwest. Eagles were counted weekly between 1978 and 2000 on a 19-km reach of the Skagit River, and oil a contiguous 24-km upriver reach between 1982 and 2000. Eagles typically occurred in greatest numbers from mid-December until the end of January: with the peak during the first 3 weeks of January. Peak 1-day counts varied from 77 in 1983-84 to 506 in 1991-92. Annual eagle detections increased since the first counts were made in 1978. but this trend has not been linear. Detections increased most rapidly from 1987-92. but have averaged about 36% below the 1991-92 peak during the last 6 years. The increase in eagle detections has been most pronounced on the upriver reach. Increases in chum salmon (Oncorhynchus keta) spawning along this reach may have resulted in proportionately greater eagle use of this area. Before 1989. the size of the Skagit chum salmon run was positively correlated with eagle detections (r = 0.81. P = 0.002). whereas frequency of peak flow events on the Skagit was negatively correlated (r = -0.81, P = 0.003). These relationships have weakened since 1988 (r = 0.58, P = 0.05, and r = 0.40. P> 0.10). Low salmon escapements on several nearby rivers between 1989-93 coincided with a peak in eagle detections on the Skagit. A subsequent rebound in these other salmon runs coincides with a return to lower eagle detections on the Skagit. The proportion of subadult eagles in the Skagit population has declined over the last 2 decades, and may reflect changes in the age structure of the regional population in the Pacific Northwest.

Roegner, G. C., B. M. Hickey, et al. (2002). "Wind-induced plume and bloom intrusions into Willapa Bay, Washington." Limnology and Oceanography 47(4): 1033-1042.

The physical oceanography and chlorophyll distribution in Willapa Bay and the adjacent coastal ocean were measured during an upwelling-downwelling wind cycle in late May 1999. Coastal conditions were determined shipboard during two sets of five cross-shelf transects conducted 4 d apart, and instrument moorings simultaneously recorded wind velocity in the nearshore zone and biophysical water properties within Willapa Bay. The results demonstrate that estuarine physical oceanography and chlorophyll concentrations were determined by processes occurring in the nearshore ocean, and these in turn were forced by variation in wind stress. At the start of the study period, southerly winds produced downwelling conditions that forced the Columbia River plume against the coast, and low salinity water was advected into Willapa Bay. This water was relatively low in chlorophyll (<2 mg m(-3)) As the winds switched to an equatorward direction, coastal upwelling ensued and the Columbia plume was replaced by cold, salty water nearshore. A phytoplankton bloom exceeding 10 mg m(-3) was generated on the shelf with its core located 10 to 40 km from the estuarine mouth. The upwelling-favorable winds then relaxed, and the bloom was apparently advected across the shelf to the coast and subsequently into Willapa Bay, where instruments recorded pulses of chlorophyll entering the estuary on flood tides. Weak downwelling conditions were prevalent for the next several days, and the Columbia River plume returned to the coast where it mixed with the chlorophyll-enriched waters in the nearshore before entering the estuary. These results demonstrate that primary productivity generated in coastal waters can be transported to estuaries, where it is likely an important yet episodic food source for estuarine organisms.

Dinnel, P. A., D. A. Armstrong, et al. (1993). "Evidence for Multiple Recruitment-Cohorts of Puget Sound Dungeness Crab, Cancer-Magister." Marine Biology 115(1): 53-63.

While sampling intertidally in Puget Sound, Washington, USA, for juvenile Dungeness crab (Cancer magister) in 1984, we found evidence of two distinct ''cohorts'' of the same year-class based on sizes of first-instar juveniles (J1) and the spatial/temporal patterns of settlement. In 1988, three distinct cohorts were observed to settle in Puget Sound and its approaches. Settlement of one cohort occurred during May in the Strait of Juan de Fuca and in those areas of Puget Sound closest to the Strait. J1 individuals of this cohort were large (xBAR = 7.4 mm carapace width, CW) and comparable in both size and timing of settlement to populations along the Washington coast (e.g. Grays Harbor and Willapa Bay). Initial settlement density of the May cohort was as high as 215 crabs/m2 in intertidal eelgrass beds along the Strait of Juan de Fuca and decreased to < 2 crabs/m2 within Puget Sound and the Strait of Georgia. A second cohort apparently originated in Hood Canal (a deep inland fjord), its size upon settlement in June was significantly smaller (J1 xBAR = 5.3 mm CW) than the May cohort, and it was limited to Hood Canal and areas of Puget Sound close to the mouth of Hood Canal. A third cohort, which settled in late July and August, was the smallest of the three cohorts (J1 xBAR = 4.8 mm CW), and was widely distributed around Puget Sound from Seattle in the south to the USA/Canadian border in the north. We hypothesize that most juvenile recruitment in Hood Canal and Puget Sound originates from parental stocks endemic to their respective basins (''Hood Canal'' and ''Puget Sound'' cohorts), but that, on occasion, oceanographic conditions allow substantial influx of Pacific Ocean Dungeness crab larvae (''oceanic'' cohort) through the Strait of Juan de Fuca into Puget Sound. Tracking of spatial/temporal settlement patterns and comparison of J1 sizes proved useful for estimating the probable sources and dispersion of Dungeness crab larvae. Differences in size and time of settlement between various larval cohorts of C. magister may prove useful as ''biomarkers'' for tracing circulation patterns within and between inland waters of Washington and the Pacific Ocean. Causes of smaller size and later settlement of the ''Puget Sound'' cohort relative to oceanic conspecifics of the same year-class are discussed.

Holsman, K. K., P. S. McDonald, et al. (2006). "Intertidal migration and habitat use by subadult Dungeness crab Cancer magister in a NE Pacific estuary." Marine Ecology-Progress Series 308: 183-195.

Tidal migrations are inherent in the life histories of numerous demersal predators, and both the indirect and direct effects of these forays are important to the structure and function of littoral communities. In coastal estuaries of the Northeastern Pacific, Dungeness crabs Cancer magister are abundant and compose a significant portion of estuarine biomass. The nursery role of complex littoral habitats for young-of-the-year (0+) C. magister is well documented, yet the ecology of subsequent age classes within coastal estuarine systems, and within littoral areas in particular, remains unclear. The goal of our study was to elucidate habitat use and migratory patterns of subadult C. magister (40 to 130 mm carapace width; 1+ and > 1+ yr classes) in littoral eelgrass Zostera marina, oyster Crassostrea gigas, and unstructured littoral habitats (ULH). We employed 3 sampling techniques (trapping, acoustic telemetry, and underwater video) designed to examine various aspects of migratory behavior within Willapa Bay, Washington, a representative coastal estuary. Baited trap surveys revealed that relative catches of subadult C. magister are 30 to 50% higher on ULH than eelgrass or oyster beds, and are negatively correlated with catches of another large cancrid crab, C. productus. Ultrasonic telemetry observations suggest that subadult C. magister making nighttime foraging incursions prefer ULH to other littoral habitats, and underwater video observations show that migrations are influenced by tidal rhythms since movements are correlated with the direction and velocity of current flow in adjacent channels. Our results dramatically alter the perception of C. magister as a predominantly sublittoral predator, and underscore the significance of littoral habitats as important foraging areas.

Labenia, J. S., D. H. Baldwin, et al. (2006). "Behavioral impairment and increased predation mortality in cutthroat trout exposed to carbaryl." Marine Ecology-Progress Series 329: 1-11.

Willapa Bay is a coastal estuary in Washington State that provides seasonal rearing habitat for anadromous cutthroat trout Oncorhynchus clarki clarki. Cutthroat trout forage throughout the estuary in the summer months when carbaryl, a carbamate insecticide, is applied to oyster beds via aerial spraying and other application methods to control burrowing shrimp populations. The insecticide interferes with normal nervous system function in trout via the inhibition of acetylcholinesterase, an enzyme that regulates neurotransmitter-mediated signaling at synapses. In the present study, we show that the olfactory system of trout is unresponsive to carbaryl, and that trout do not avoid seawater containing the pesticide at environmentally representative concentrations. Short-term (6 h) carbaryl exposures significantly reduced acetylcholinesterase activity in both brain and muscle in a dose-dependent manner. Enzyme activity gradually recovered over 42 h following carbaryl exposure (6 h at 500 mu g l(-1)). In tests of swimming performance, trout were unable to orient to directional flow and swim effectively at exposure concentrations >= 750 mu g l(-1). Finally, we determined rates of predation by lingcod Ophiodon elongatus on carbaryl-exposed and unexposed trout. Exposed animals were consumed by predators at significantly higher rates at concentrations >= 500 mu g l(-1). We conclude that cutthroat trout are unlikely to avoid carbaryl-contaminated seawater, and that estuarine applications are likely to cause neurobehavioral impairments in trout that may increase individual mortality due to predation.

Ruesink, J. L., B. E. Feist, et al. (2006). "Changes in productivity associated with four introduced species: ecosystem transformation of a 'pristine' estuary." Marine Ecology-Progress Series 311: 203-215.

Multiple stressors in estuaries can cause declines in native species and impairment of ecosystem goods and services. In contrast, one stressor-the introduction of non-native species-actually leads to higher local richness. We examined the changes in ecosystem function associated with introductions into Willapa Bay, Washington, USA, a relatively undeveloped estuary with 45 documented exotic marine species. The replacement of native oysters by 2 new bivalve species has increased secondary production of harvested suspension feeders by 250 % over peak historic values (3.3 x 10(5) vs. 0.9 x 10(5) kg dry wt yr(-1)), based on > 150 yr of records of harvested biomass. Key aspects of aquaculture-particularly planted area-have remained constant over time, so we attribute much of the altered secondary production to higher growth rates of non-native species. The addition of 2 tracheophytes has increased primary production on the tideflats by > 50%, (5.3 x 10(7) vs. 3.5 x 10(7) kg dry wt yr(-1)), which we calculated by scaling up local measurements of plant growth to the total area occupied by each species. These changes in production are also associated with altered detritus, water filtration, and biogenic habitat. Because other stressors are largely absent from Willapa Bay, the addition of particular exotic species has dramatically enhanced system production, while fundamentally reshaping the ecological character of the estuary. These strong ecological impacts of introduced species have rarely been measured at whole-ecosystem scales, and they occur in part because new species occupy habitats where similar native species were not present.

Komar, P. D. and M. Z. Li (1991). "Beach Placers at the Mouth of the Columbia River, Oregon and Washington." Marine Mining 10(2): 171-187.

Four black-sand placer deposits exist in proximity to the mouth of the Columbia River on the northwest coast of the United States. The deposits have attracted attention for potential exploitation due to their contents of magnetite and ilmenite. The focus of our study is on the modes of formation of these placers, and on the grain-sorting patterns and processes. The most concentrated deposits are found on the modern beaches immediately north and south of the river mouth. These beaches owe their existence to the construction of the jetties on the Columbia, and it is likely that placer development has resulted in part from beach erosion adjacent to the jetties. The heavy-mineral concentrations are greatest at the river mouth, and decrease systematically with longshore distance both to the north and south. The patterns of sorting of the minerals according to their contrasting densities and grain sizes indicate that processes of selective entrainment have been primarily responsible for concentrating the placer sands. Two additional black sand deposits are located on opposite shores of the Columbia River in areas that would have been the active mouth prior to jetty construction. It is likely that they formed during periods of shoreline erosion induced by the natural migration of the river's mouth, much as is presently taking place along Cape Shoalwater at the mouth of Willapa Bay on the Washington coast.

Dumbauld, B. R., K. M. Brooks, et al. (2001). "Response of an estuarine benthic community to application of the pesticide carbaryl and cultivation of pacific oysters (Crassostrea gigas) in Willapa Bay, Washington." Marine Pollution Bulletin 42(10): 826-844.

Oyster culture operations on the West coast of North America have developed into complete farming operations for the introduced Japanese oyster, Crassostrea gigas, which now covers vast areas of the intertidal landscape, particularly in Washington State where the pesticide carbaryl has also been used to control burrowing thalassinid shrimp for more than 30 years. Field experiments were conducted to examine the effects of these habitat modifications on the benthic community in Willapa, Bay Washington (124 degrees 06'W,46 degrees 24'N) where 50% of the state's oyster production occurs. Results indicated that the primary long-term effect of carbaryl application was removal of the two species of thalassinid shrimp (Neotrypaea californiensis and Upogebia pugettensis), which dominated the community at the start of the experiment and clearly influenced community composition themselves. Small peracarid crustaceans like the amphipods Corophium acherusicum and Eohaustorius estuarius experienced the most significant short-term mortalities, but generally recruited back to treated sites within 3 months, and were often more abundant on treated than untreated sites 1 year after carbaryl application. Results for molluscs were mixed, with no significant effect on Macoma spp, but a significant effect on the commensal clam Crytomya californica and mixed results for the cockle Clinocardium nutalli. Polychaetes were the least susceptible to carbaryl and with the exception of a short-term effect on oligochaetes, no significant negative effects were observed. The addition of oysters did not affect the infaunal community in this study, however greater abundance of epifaunal organisms like mussels, scaleworms, and the amphipod Amphithoe valida, which builds tubes in algae attached to shells, was observed. Carbaryl, which is currently applied to roughly 242 ha (< 6% of the intertidal) in Willapa Bay on an annual basis, has a variable but relatively short-term effect on the benthic community, which should be viewed in the context of other oyster culture operations like the addition of oysters themselves to a community often dominated by burrowing thalassinid shrimp which clearly control its dynamics. (C) 2001 Elsevier Science Ltd. All rights reserved.

Stiller, J. W. and A. L. Denton (1995). "100 Years of Spartina-Alterniflora (Poaceae) in Willapa Bay, Washington - Random Amplified Polymorphic DNA Analysis of an Invasive Population." Molecular Ecology 4(3): 355-363.

Spautina alterniflora (smooth cordgrass) has invaded Willapa Bay, Washington, covering bare mud flats and seagrass beds. At current expansion rates it threatens to occupy most of the intertidal habitat in the bay within 40 years. Although a major mitigation effort is underway, nothing is known about the genetic structure of the Willapa Bay S. alterniflora population or the underlying causes for the dramatic increase in seed set that has occurred in the last 15 years. Random amplified polymorphic DNA (RAPD) analysis was assessed as a method of DNA fingerprinting to analyse the genetic history and current structure of the Willapa population. The results suggest that all S. alterniflora clones in Willapa Bay are descended from a single genet. Given the limited genetic variability expected in a clonally founded population, we discuss the utility of RAPDs as genetic markers to explore the large morphological and reproductive differences reported among Willapa clones. Cluster analysis of RAPD fragments was used to show relatedness among S. alterniflora genets and may be helpful in locating the most prolific clones for mitigation efforts. Overall, RAPDs show great potential in genetic analysis of S. alterniflora, particularly in invasive populations where isozyme variability is low or nonexistent.

Connor, E. J. and D. E. Pflug (2004). "Changes in the distribution and density of pink, chum, and Chinook salmon spawning in the upper Skagit River in response to flow management measures." North American Journal of Fisheries Management 24(3): 835-852.

We analyzed the abundance and spatial distribution of spawning pink salmon Oncorhynchus gorbuscha, chum salmon O. keta, and Chinook salmon O. tshawytscha in a 27-mi section of the upper Skagit River, Washington, regulated by the Skagit Hydroelectric Project. Densities of spawning salmon were compared among three contiguous reaches of the upper Skagit River before and after the implementation of flow management measures in 1981. The measures were intended to minimize redd dewatering during the spawning and incubation periods and fry stranding during the emergence and outmigration periods. Field monitoring confirmed that increasing the minimum incubation flows created improvements in redd protection levels. Greater protection of fry from stranding was achieved by substantially reducing the annual number of downramping events and by reducing downramping during daytime, when fry are most vulnerable to stranding. Spawner abundance of all three species progressively increased in an upstream direction following implementation of flow measures; increases were greatest in the reach immediately below the hydroelectric project. The upstream shift in spawner abundance was highly significant based on factorial analyses of variance. The greatest increases in spawner abundance for Chinook salmon and chum salmon were observed during even years, when pink salmon did not spawn. Mean spawner abundance in the upstream-most study reach increased from 311 to 1,169 carcasses/mi (odd years) for pink salmon, from 6 to 115 fish/mi (odd years) or 58 to 462 fish/mi (even years) for chum salmon, and from 48 to 49 redds/mi (odd years) or 59 to 65 redds/mi (even years) for Chinook salmon. The total number of pink salmon and chum salmon spawners significantly increased within the study area after 1981. These increases were substantially greater than those observed concurrently in other areas of the Skagit River basin and in other northern Puget Sound rivers. The average number of Chinook salmon spawners remained unchanged in the study area after 1981, while substantially declining in other unregulated Skagit River subbasins and most Puget Sound rivers. The study area now possesses the greatest percentage of pink, chum, and Chinook salmon spawners within the Skagit River basin. The Skagit River presently supports the largest run of native Chinook salmon in the Puget Sound region and the largest runs of pink and chum salmon in the coterminous United States.

Hemphillhaley, E. (1995). "Intertidal Diatoms from Willapa Bay, Washington - Application to Studies of Small-Scale Sea-Level Changes." Northwest Science 69(1): 29-45.

Sea-level reconstructions using estuarine diatoms are generally constrained by the absence of detailed ecological data regarding the distributions of modern intertidal species. As part of an on-going study to assess the biostratigraphic record of relative sea-level changes triggered by earthquakes in the Pacific Northwest, modern intertidal diatoms were collected in surface samples from northern Willapa Bay, Washington. Q-mode factor analysis was used to classify assemblages from tidal flats and banks, shallow subtidal channels, low and high marshes along two intertidal transects on the Niawiakum River, and in intertidal samples from the open bay. Autochthonous taxa dominated the assemblages, but in some cases probable allochthonous taxa scored relatively high in the factor analysis. The results of the analysis suggests that diatoms can be used to identify three elevational zones relative to tidal level: (1) intertidal flats, channel banks, and shallow subtidal channels, below approximate mean lower high water (MLHW); (2) low marshes approximately between MLHW and mean higher high water (MHHW; and (3) high marshes approximately between MHHW and extreme high water (EHW). The marsh-upland transition, near EHW, coincides with the terminus of regular diatom productivity and is recognizable by the disappearance of high-marsh diatoms in soil deposits. Absolute elevations of the ecological zones are constrained by local tidal range. Because of the cosmopolitan distributions of many of the species observed in this study, these data are probably applicable to studies of Quaternary sea-level change and paleoseismicity throughout the coastal Pacific Northwest.

Michael, J. H. (1998). "Pacific salmon spawner escapement goals for the Skagit river watershed as determined by nutrient cycling considerations." Northwest Science 72(4): 239-248.

Wild populations of Pacific salmon (Oncorhynchus spp.) in Washington State are generally at low levels compared to populations that were likely present before the arrival of Euro-Americans in the Pacific Northwest. Habitat loss, the introduction of non-native stocks and species, and overfishing have all contributed to the decline. Historically, huge numbers of salmonid carcasses provided entire watersheds with nutrients derived from the ocean. Diminished populations and transport of these nutrients out of watersheds has caused a nutrient deficiency compared to times when populations were large. This nutrient deficiency may be hampering recovery of salmon and other animal populations. Beginning with the premise that the Pacific Northwest ecosystem evolved to fully utilize massive numbers of spawning salmon, I estimated the biomass of salmon carcasses necessary to support nesting song birds, wintering bald eagles, and salmonid smolt production in the Skagit River watershed in Washington. The proposed spawner escapement goals thus estimated are 150% to 680% higher than current spawner escapement goals for salmon in the watershed The justifications for these proposed gears include comparison with escapement goals used in other watersheds, the actual uptake of marine-derived nutrients by fish, the impact of increased escapement on subsequent smelt production, and actual relationships between adult spawners and smolts in less intensively fished streams. Actual attainment of these goals will need to consider the physical condition of the watershed and its ability to retain and cycle the nutrients and the social and economic disruption to fisheries that may result from allowing more fish to survive to adulthood and spawn.

Stimac, M. V. (1975). "Impact of Zoning on Siting of Skagit Nuclear-Power Project." Nuclear Technology 25(4): 722-723.

Johnson, P. (1985). "The Bowl at the Center of the World - Edges and Pathways in the Skagit Estuary." Oceans 18(1): 34-47.

Daehler, C. C. and D. R. Strong (1997). "Reduced herbivore resistance in introduced smooth cordgrass (Spartina alterniflora) after a century of herbivore-free growth." Oecologia 110(1): 99-108.

We compared resistance to insect herbivory in two introduced populations of smooth cordgrass (Spartina alterniflora) differing in their history of herbivory. One population in Willapa Bay, Washington, has spread in the absence of herbivory for more than a century, while another population in San Francisco, California, was introduced 20 years ago and is fed upon by the Spartina-specialist planthopper, Prokelisia marginata. The planthopper is a sap-feeder common on the Atlantic and Gulf coasts of North America, where smooth cordgrass is native. Smooth cordgrass plants from Willapa Bay (WB), San Francisco Bay (SFB), and Maryland (the source of the SFB introduction) were exposed to P. marginata herbivory over two consecutive summers in a common greenhouse environment, and their growth was compared with that of control plants that were grown herbivore-free. The planthoppers had relatively little effect on the growth of SFB plants, with plants exposed to herbivores averaging 77% and 83% of the aboveground biomass of herbivore-free controls after the first and second season of herbivory, respectively. The growth of plants from Maryland was similarly little-affected by the planthoppers, with the plants exposed to herbivores averaging near 100% of the biomass of herbivore-free controls after two seasons. In contrast, the growth of the WB plants was greatly reduced by the planthopper, with the plants exposed to planthopper herbivory averaging only 30% and 12% of the aboveground biomass of herbivore-free controls after the first and second seasons of herbivory, respectively. By the end of the second season of herbivory, 37% of the WB plants exposed to herbivory had died, while none of the SFB plants exposed to herbivores had died. Among WB clones, there was variation in resistance; one WB clone suffered 0% mortality while another suffered 100% mortality when exposed to herbivores. Short-term herbivory experiments with the putative founder clone for the WB population suggested that the WE founder was similar to the more resistant WB clones in its susceptibility to planthopper herbivory. Nitrogen analyses of green leaf tissue indicated that WB plants, including the WB founder clone, averaged 70% more total leaf nitrogen than SFB and Maryland plants. In a planthopper choice experiment, more planthoppers were observed on WB plants than SFB plants after 95 days of exposure to herbivory. Planthopper preference for WB plants may have contributed to the lower resistance of WB plants to herbivory; however, even before planthoppers had become more abundant on the WB plants, the proportion of leaves with 50% or more dead tissue averaged significantly greater on the WB plants, suggesting a difference between populations in tolerance to herbivory as well. Multiple factors, including a founder effect, further loss of herbivore tolerance, and herbivore preference for WB plants, appear to account for the reduced planthopper resistance in the WB population.

Gingras, M. K., S. G. Pemberton, et al. (2001). "Bathymetry, sediment texture, and substrate cohesiveness; their impact on modern Glossifungites trace assemblages at Willapa Bay, Washington." Palaeogeography Palaeoclimatology Palaeoecology 169(1-2): 1-21.

Glossifungites-demarcated discontinuities have been demonstrated to have stratigraphic significance. Unfortunately, their stratigraphic utility commonly eclipses the palaeoecological information derived from such surfaces. This paper attempts to identify factors that influence the nature of trace assemblages observed in modem firmgrounds. In particular, it focuses on the causes of lateral variability and erosional topography inherent to Glossifungites surfaces. The extensive Pleistocene database at Willapa Bay is used to test the interpretations. Striking heterogeneity in Gloosifungites assemblages is documented from modern firmgrounds at Willapa Bay. This variability is related to intertidal zonation, sediment texture, the absolute firmness of the firmground, and the presence or absence of a sediment veneer. Generally, subtidal and lower- to middle-intertidal firmgrounds are colonized by crustaceans (the Upogebia Association) or the bivalve Petricola (the Petricola Association). These surfaces are characteristically burrowed with Thalas-sinoides- and Gastrochaenolites-like traces. The upper intertidal is dominated by the Polydora Association, the burrows of which include diminutive Diplocraterion and Arenicolites-like traces. Sandy and heterolithic substrates are avoided by burrowing crustaceans and polychaetes alike. In contrast, Petricola is observed in muddy, sandy-mud, and heterolithic substrates. Therefore, where colonized, sandier substrates are dominated by the clavate, Gastrochaenolites-like burrows produced by these bivalves. The absolute firmness of exhumed firmgrounds is quite variable. The Upogebia Association is absent in substrates that exceed 10(9) Pa. Polydora-dominated assemblages are poorly developed in similar firmgrounds. The Petricola Association, however, is well-developed in relatively firm substrates. Finally, the morphologic characteristics of exhumed (modern) firmgrounds show that the history of a Glossifungites-demarcated surface can be extremely dynamic. Firmground surfaces are exposed to an array of physico-chemical conditions as they are exhumed, colonized, and pass into the geological record. These surfaces are commonly re-exhumed due to auto- and allocyclic processes. (C) 2001 Elsevier Science B.V. All rights reserved.

Buatois, L. A., M. K. Gingras, et al. (2005). "Colonization of brackish-water systems through time: Evidence from the trace-fossil record." Palaios 20(4): 321-347.

Trace fossils in estuarine deposits of different ages have been compared to evaluate colonization history of brackish-water ecosystems and to calibrate trace-fossil, brackish-water models with respect to geologic time. This comparative analysis reveals that, although the colonization of marginal-marine, brackish-water environments was a long-term process that spanned most of the Phanerozoic, this process of invasion of fully marine organisms into restricted, marginal-marine habitats did not occur at a constant rate. Five major colonization phases can be distinguished. The first phase (Ediacaran-Ordovician) represents a prelude to the major invasion that occurred during the rest of the Paleozoic. While Ediacaran-Cambrian ichnofaunas seem to be restricted to the outermost zones of marginal-marine depositional systems, Ordovician assemblages show some degree of landward expansion within brackish-water ecosystems. Intensity of bioturbation and ichnodiversity levels were relatively low during this phase. The second phase (Silurian-Carboniferous) is marked by the appearance of more varied morphologic patterns and behavioral strategies, resulting in a slight increase in ichnodiversity While previous assemblages were arthropod dominated, brackish-waterSilurian-Carboniferous ichnofaunas include structures pro- duced by bivalves, ophiuroids, and polychaetes. Ichnofaunas from the third phase (Permian-Triassic) seem to be characterized by the presence of crustacean burrows, reflecting the late Paleozoic crustacean radiation and adaptation of some groups to brackish-water conditions. The fourth phase (Jurassic Paleogene) is typified by a remarkable increase in ichnodiversity and intensity of bioturbation of estuarine facies. Colonization occurred not only in softgrounds and firmgrounds, but also in hardgrounds and xylic substrates. The fifth phase (Neogene Recent) records the onset of modern brackish-water benthos. Although still impoverished with respect to their fully marine counterparts, brackish-water ichnofaunas may reach moderately high diversities, particularly in middle- and outer-estuarine regions, and degree of bioturbation may be high in certain estuarine sub-environments. Comparative analysis of brackish-water ichnofaunas through geologic time provides valuable evidence to understand colonization of marginal-marine environments through the Phanerozoic, and allows for calibration of ichnologic models that may aid in the recognition of estuarine valley-fill deposits in the stratigraphic record.

Campbell, K. A. and E. A. Nesbitt (2000). "High-resolution architecture and paleoecology of an active margin, storm-flood influenced estuary, Quinault Formation (Pliocene), Washington." Palaios 15(6): 553-579.

An exhumed Pliocene estuarine sequence is preserved in exquisite detail in the Quinault Formation of coastal western Washington. The thick fill of the Quinault estuarine basin. (similar to 700 m) represents a single transgressive-regressive system that was punctuated by subduction-related tectonic events, and may reflect erosion and sediment accumulation during accelerated uplift of the Olympic Mountains in, the Pliocene. Sedimentation patterns in the ancient Quinault estuary were influenced strongly both by floods on the paleo-Quinault River, and by storm waves on the high-energy, open Pacific coast. Body fossils were derived from both marine and brackish faunal elements. Trace fossil suites indicate that the benthos flourished in the fluctuating physicochemical conditions of an estuary in dynamic equilibrium. An estuarine-specific trace fossil, a new ichnospecies of Psilonichnus that is attributed to burrows of the mud shrimp Upogebia pugettensis, is restricted to inlet-mouth, muddy sandstone facies. The marine-marginal marine transition is well-preserved in Quinault estuarine strata (exposed in the Point Grenville and Cape Elizabeth areas), as evidenced by: (I) distinctive sedimentologic signatures characteristic of lower shoreface, estuarine mouth, central basin, tidal creek/flat, and fluvial subenvironments; and (2) systematic changes in trace fossil associations in the up-estuary direction, from Skolithos ichnofacies elements to a mixed Skolithos-Cruziana assemblage to Glossifungites associations with rhizome phytoburbation. Hence, Quinault strata record a classic tripartite division of an ancient estuarine system, allowing a fine-scale delineation of subenvironments in an active tectonic regime.

Gingras, M. K., S. M. Hubbard, et al. (2000). "The significance of Pleistocene Psilonichnus at Willapa Bay, Washington." Palaios 15(2): 142-151.

Two types of ichnofossils from Pleistocene outcrop at Willapa Bay are described. Because both trace fossils are characterized by an inclined to horizontal tunnel, are unlined, have an exaggerated J-shaped morphology: rarely branch, and have an unconstricted apertural opening, they have been classified as Psilonichnus upsilon Type A and B. Psilonichnus upsilon Type A is generally 1 to 3 cm in diameter and is infilled with. laminated sediment In general, P. upsilon Type A is observed in ancient point-bar deposits. It has an extremely simple architecture that is almost identical to that produced by the crab Hemigrapsus oregonensis in modern tidal flats at Willapa: Bay. Psilonichnus upsilon Type B normally exceeds 10 cm diameter and is infilled with laminated sediment, The passive infill commonly is deposited in couplets and may be delivered to the burrow network by tide-generated currents. Psilonichnus upsilon Type B is observed in intertidal flat deposits. The overall morphology of this trace fossil is most similar to burrows generated by large crustaceans such as crabs, stomatopods, and lobsters. The occurrence of these traces leads to four findings: (1) Psilonichnus upsilon has a more variable architecture than discussed in the literature. The size and angle of the tunnel are variable, and Psilonichnus may aggrade, forming Teichichnus-like structures. (2) In the modern bay, burrowing shrimp dominate subtidal point-bar, and intertidal deposits. The Pleistocene record indicates that burrowing crabs sometimes occupied similar niches in the ancient bay. (3) Laminated, heterolithic burrow fills provide evidence of rhythmic sedimentation. These laminae represent tidal or episodic sedimentation and provide the only evidence of such. processes in otherwise muddy deposits. (4) A large burrowing crab that might make P. upsilon Type B may not be present in the modern bay. However, such a trace maker was present when these Pleistocene deposits accumulated.

Gingras, M. K., J. A. Maceachern, et al. (2004). "Modem perspectives on the Teredolites ichnofacies: Observations from Willapa Bay, Washington." Palaios 19(1): 79-88.

This study details occurrences of Teredolites ichnocoenoses from modern bay-margin settings in Willapa Bay, Washington. In particular, the paper scrutinizes in situ log-grounds from two intertidal zones situated immediately seaward of low-lying, supratidal, forested marshlands that are fed by small streams. Vestiges of remnant marshes and streams are preserved on intertidal flats as in-situ roots, broken stumps, strewn logs, abundant organic detritus, and organic sandy mud. Xylic material and organic sediment were deposited in the supratidal marshes: tide and wave processes truncated the swamps, exposing in situ tree-root networks and the lowermost supratidal sediments. Stream and swamp deposits overlie and incise older Pleistocene strata. Both units are overlain by discontinuous, modern intertidal deposits. The intertidally exposed stumps and logs support a diverse community of animal and plant life. Boring organisms, encrusters, and refugium seekers are found on and within the xylic substrates. Some encrusting animals and all of the boring fauna produce traces that are comparable to ichnofossils reported by palichnologists. Wood-boring traces reported in this study are similar morphologically to the ichnogenera Caulostrepsis, Entobia, Meandropolydora, Psilonichnus, Rogerella, Teredolites, Thalassinoides, and Trypanites. Most of these ichnogenera have not been reported from rock-record examples of the Teredolites ichno-facies. The stratigraphic and environmental significance of the reported (modern) locales is consistent with previous studies that associate Teredolites ichnofacies with base-level rise in marginal-marine environments. At Willapa Bay, bored xylic media form a coeval surface with adjacent, burrowed firmgrounds as well as softgrounds.

Gingras, M. K., S. G. Pemberton, et al. (1999). "The ichnology of modern and Pleistocene brackish-water deposits at Willapa Bay, Washington: Variability in estuarine settings." Palaios 14(4): 352-374.

Detailed analysis of modern and Pleistocene deposits at Willapa Bay, Washington concentrated on identifying ichnological and sedimentological characteristics of five estuarine subenvironments. These include: (1) intertidal flat deposits, which are typically thoroughly bioturbated by a somewhat diminutive suite of various vertical and horizontal shafts and burrows that are locally cross-cut by robust crustacean dwellings; (2) unburrowed to rarely burrowed tidal creek point-bar deposits, which are sporadically burrowed by minute Gyrolithes, Skolithos, Cylindrichnus, Planolites, Palaeophycus, and rare bivalve equilibrichnia; (3) fluvially- through tidally-influenced main point-bar deposits, which are sporadically bioturbated with vertical traces superimposed upon inclined heterolithic stratification; (4) well to thoroughly bioturbated bay deposits, burrowed by relatively robust forms of Ophiomorpha, Teichichnus, Skolithos and bivalve equilibrichnia; and (5) locally bioturbated channel-bar deposits, typically displaying robust bivalve equilibrichnia, rare Ophiomorpha, and deep-penetrating Skolithos. Traces from both the modern and ancient deposits display a marked reduction in size and diversity in the upper estuary. Ongoing research at Willapa Bay confirms the validity of the brackish-water model and provides data that potentially improve our understanding of these deposits. Our findings suggest that strong textural controls are overprinted by salinity stresses; commonly vertical deposit-feeding structures, made by infauna that are mining and/or stoping organic-rich laminae, are present; and there is a potential for the presence of large diameter crustacean burrows in brackish deposits. This research emphasizes ichnologic variability due to autocyclic changes and climatic variability, and urges caution when integrating ichnologic and sedimentologic data into a genetic stratigraphic model.

Gingras, M. K., R. Pickerill, et al. (2002). "Resin cast of modern burrows provides analogs for composite trace fossils." Palaios 17(2): 206-211.

A neoichnological resin cast of modern burrows from a mudflat at Willapa Bay, Washington, reveals much of the architecture of the infaunal community present locally within sediments of this mudflat. The cast structures comprise Psilonichnus-, Skolithos-, Trichichnus-, Chondrites(?)-, Planolites-, Palaeophycus-, and Arenicolites-like burrows. The range of behaviors represented by these structures cannot be classified into an archetypal (Seilacherian) ichnofacies. The resin cast contains many coeval, composite burrows that may reflect certain commensal relationships. Notable composite associations include: (1) siphon shafts of Mya arenaria that are connected to and descend from crab domiciles; (2) an example of a pair of infaunal Mya arenaria that share a single siphonate shaft; (3) abundant Heteromastus burrows that connect to crab and bivalue burrows; and, (4) Nereis burrows that are connected to crab domiciles. It is suggested that such contemporaneous relationships, if passed into the fossil record, might be misinterpreted as representing tiering or faunal succession. The reported observations provide a new perspective on the potential significance of interpenetrating trace fossils and complex ichnofabrics.

Nesbitt, E. A. and K. A. Campbell (2006). "The paleoenviromnental significance of psilonichnus." Palaios 21(2): 187-196.

The ichnogenus Psilonichnus and its named ichnospecies are evaluated for their utility in paleoenvironmental reconstructions. A combined ichnological-sedimentological model for shoreface-estuarine-fluvial settings is presented herein to show distributions of the ichnospecies of Psilonichnus in an ichnofacies framework. High-resolution differentiation of coastal paleoenvironments may be achieved in strata containing Psilonichnus only if the trace fossils are identified to ichnospecies level, and if they are assessed as sedimentary structures within a depositional context. The simple Y, J-, and I-shaped, vertical to inclined burrows referred to as Psilonichnus include three distinct ichnospecies-P. tubiformis, P. upsilon, and P. lutimuratus. Each can be attributed to either of two decapod crustacean progenitors, thalassinoid mud shrimp, or ocypodid ghost crabs. The ichnogenus occurs in association with the Psilonichnus, Glossifungites, and Skolithos ichnofacies in estuary / bay to backshore / dune sedimentary settings. Psilonichnus has proved to be an effective paleoenvironmental indicator, especially in studies of sequence stratigraphy, To date, however, inconsistencies in both ichnotaxonomic and ichnofacies assignments for Psilonichnus, and confusion regarding probable tracemakers, have diminished its usefulness to sedimentary geology. To avoid such problems, each new field occurrence of a potential Psilonichnus trace must be evaluated thoroughly within its biological, ecological, and physical context.

King, G. M., C. Giray, et al. (1994). "A New Hemichordate, Saccoglossus-Bromophenolosus (Hemichordata, Enteropneusta, Harrimaniidae), from North-America." Proceedings of the Biological Society of Washington 107(2): 383-390.

A new species. S. bromophenolosus, is distinguished from its congener, S. kowalevskii (Agassiz 1873), on the basis of the following morphological, biochemical, and genetic criteria: placement of gill pores; prominence of the dorsal ridge; structure of the proboscis skeleton; presence of bromophenols or bromopyrroles; relative electrophoretic mobility of allozymes (e.g., superoxide dismutase); molecular weights of fragments from restriction endonuclease digestion of mitochondrial DNA. S. bromophenolosus occurs from southern Maine, U.S.A., to Nova Scotia, Canada, with an additional record from Willapa Bay, Washington, U.S.A.

Kilfeather, A. A., J. J. Blackford, et al. (2007). "Micromorphological analysis of coastal Sediments from Willapa Bay, Washington, USA: A technique for analysing inferred tsunami deposits." Pure and Applied Geophysics 164(2-3): 509-525.

Tsunami deposits are provisionally distinguished in the field on the basis of anomalous sand horizons, fining-up and fining-landward, coupled with organic-rich, fragmented 'backwash' sediments. In this paper, micromorphological features of a sediment sequence previously interpreted as being of tsunami origin are described. These characteristics are shown to be consistent with the macro-scale features used elsewhere, but show additional details not seen in standard stratigraphies, including possible evidence for individual waves, possibly wave-magnitude progression, organic fragment alignment and intraclast microstructures. Although replication and more complete studies are needed, this analysis confirms the identification of a tsunami in Willapa Bay in ca. 1700 AD, while demonstrating a widely applicable technique for confirming or refuting possible tsunami deposits.

Benson, B. E., B. F. Atwater, et al. (2001). "Renewal of tidal forests in Washington state after a subduction earthquake in AD 1700." Quaternary Research 56(2): 139-147.

With few exceptions, today's tidal trees near Washington's Pacific coast postdate an earthquake that lowered the region by 1 m or more. The earthquake, which occurred in A.D. 1700, is the most recent to have ruptured much of the plate boundary at this central part of the Cascadia subduction zone. Because of the coseismic subsidence, lowland forests became tidal flats where thousands of trees died. Most of the trees killed were Sitka spruce (Picea sitchensis). In the centuries since the earthquake, tidal deposits have built new land that has been colonized by new Sitka spruce. All but several tens of the region's tidal spruce consequently postdate 1700, as shown by counts of annual rings in 121 of the largest spruce in tidal forests at Copalis River, Grays Harbor, and Willapa Bay. Forests began to return to each of these estuaries in the early 1700s and spread seaward in the late 1700s and 1800s. Annual rings in the oldest of the trees thus record a large fraction of the earthquake-recurrence interval that began with the 1700 earthquake. (C) 2001 University of Washington.

Luepke, G. and H. E. Clifton (1983). "Heavy-Mineral Distribution in Modern and Ancient Bay Deposits, Willapa Bay, Washington, USA." Sedimentary Geology 35(4): 233-247.

Rebata, L. A., M. K. Gingras, et al. (2006). "Tidal-channel deposits on a delta plain from the Upper Miocene Nauta Formation, Maranon Foreland Sub-basin, Peru." Sedimentology 53(5): 971-1013.

Miocene siliciclastic sediments of the Maranon Foreland Sub-basin in Peru record the sedimentary response to regional marine incursions into Amazonia. Contrary to previous interpretations, the Late Miocene Nauta Formation provides evidence of the last known marine incursion before the current Amazonia river basin became established. Sedimentological, ichnological and palynological data from well-exposed outcrops along a ca 100 km road transect suggest that the Nauta Formation represents a shallow, marginal-marine channel complex dominated by tidal channels developed in the inactive, brackish-water portions of a delta plain. The main facies associations are: FA1 - slightly bioturbated mud-draped trough cross-stratified sand; FA2 - locally, pervasively bioturbated inclined heterolithic stratification (IHS); and FA3 - moderately bioturbated horizontally bedded sand-mud couplets. These identify subtidal compound dunes, tidal point bars and shallow subtidal to intertidal flats, respectively. Bi-seasonal depositional cycles are ascribed to the abundant metre- to decimetre-scale sand-mud couplets that are found mainly in the IHS association: semi-monthly to daily tidal rhythmicity is inferred from centimetre- and millimetre-scale couplets in the mud-dominated parts of the decimetre-scale couplets. The ichnology of the deposits is consistent with brackish depositional conditions; the presence of Laminites, a variant of Scolicia, attests to episodic normal marine conditions. Trace fossil suites are assigned to the Skolithos, Cruziana and mixed Skolithos-Cruziana ichnofacies. Pollen assemblages related to mangrove environments (e.g. Retitricolporites sp., Zonocostites sp., Psilatricolporites maculosus, Retitricolpites simplex) support a brackish-water setting. Uplift of the Merida Andes to the North and the consequent closure of the Proto-Caribbean connection, and the onset of the transcontinental Amazon drainage, constrain the deposition of the Nauta sediments with around 10 to 8 Ma, probably contemporaneous to similar marine incursions identified in the Cuenca (Ecuador), Acre (Brazil) and Madre de Dios (Southern Peru) (sub)basins, and along the Chaco-Paranan corridor across Bolivia, Paraguay and Argentina.

Hurlow, H. A. (1993). "Midcretaceous Strike-Slip and Contractional Fault Zones in the Western Intermontane Terrane, Washington, and Their Relation to the North Cascades-Southeastern Coast Belt Orogen." Tectonics 12(5): 1240-1257.

Structural and geochronologic data from the 111-114 Ma Okanogan Range batholith in north central Washington are used to characterize the timing and style of deformation during the early stages of the mid- to Late Cretaceous North Cascades-southeastern Coast Belt (NC-SECB) orogen. The Pasayten fault zone bounds Jurassic-Cretaceous sedimentary and volcanic rocks of the Methow basin to the west against predominantly Mesozoic igneous rocks of the Intermontane terrane to the east. The Pasayten fault zone accommodated intrusion of the western units of the Okanogan Range batholith during high-angle slip, then approximately 20 km of left-lateral strike-slip at 109-95 Ma. South of the Pasayten fault zone, the Red Shirt and Methow River thrust zones accommodated (1) west vergent contraction at amphibolite grade that began by 113 Ma and ended by 112 Ma, based on new U-Pb zircon dates for deformed and undeformed granitoids, and (2) northwest vergent contraction in the Methow River thrust zone followed by west vergent contraction in the Red Shirt thrust zone, both at greenschist grade prior to 104 Ma. These contractional displacements thrust the Methow basin 10-20 km southeastward beneath the western Okanogan Range batholith. Deformation in the NC-SECB thus began by earliest Albian time, earlier than previously thought and was characterized by coeval sinistral transcurrent and west vergent contractional faulting. Sinistral strike-slip in the Pasayten fault zone may have reflected the pre-100 Ma sense of oblique plate convergence or relatively minor southward tectonic escape of the adjacent Methow basin during contractional deformation. The slip history of the Pasayten fault zone is undocumented between approximately 80 Ma and 60 Ma when, on the basis of paleomagnetic data, some workers have proposed that the Methow basin moved 1700 km northward to its present position relative to the Intermontane terrane. However, significant Late Cretaceous to Early Eocene dextral slip on the Pasayten fault zone is unlikely because the western intrusive, units of the Okanogan Range batholith continue without disruption across its southeastward trend.

Matzel, J. E. P., S. A. Bowring, et al. (2004). "Protolith age of the Swakane Gneiss, North Cascades, Washington: Evidence of rapid underthrusting of sediments beneath an arc." Tectonics 23(6).

[1] The metamorphic core of the North Cascades largely comprises island arc and oceanic terranes juxtaposed prior to circa 96 Ma magmatism. However, the tectonic affinity of the structurally deepest terrane, the 9 - 12 kbar Swakane Gneiss, is distinctly different from other terranes in the core; it is not intruded by arc-related plutons and contains abundant Precambrian zircons. New U-Pb analyses of detrital zircons from the Swakane Gneiss yield dates from 73 Ma to 1610 Ma with a dominant Late Cretaceous population. These data indicate that the Swakane protolith was deposited as late as 72.5 +/- 0.6 Ma, the Pb-206/U-238 date of the youngest detrital grain. Following deposition, the gneiss was intruded by peraluminous leucogranite sheets that may represent partial melt derived from the gneiss at near- to postpeak P-T conditions. One sheet yielded a U-Pb crystallization age of 68.36 +/- 0.07 Ma, which indicates that the gneiss was deeply buried within 5 Myr of deposition. Two possible mechanisms considered for this rapid burial ( similar to 7 mm/yr) are overthrusting of a forearc or back arc basin by older crystalline rock or underthrusting of trench sediments during low-angle subduction. The model involving overthrusting of a forearc or back arc basin is most consistent with thermobarometric and isotopic data and the regional geologic setting of the Cascades core. Rapid burial of the Swakane protolith is coincident with burial of sediments that formed the Pelona, Orocopia and Rand schists of southern California; however, differences in peak metamorphic temperatures indicate that conditions of burial must have varied along the plate margin.

Paterson, S. R., R. B. Miller, et al. (2004). "Driving mechanisms for > 40 km of exhumation during contraction and extension in a continental arc, Cascades core, Washington." Tectonics 23(3).

[1] In the NW North American Cordillera, the Cascades core region of the Coast Plutonic Complex underwent Late Cretaceous (> 96 Ma to locally 73 Ma) SW-NE contraction and crustal thickening followed by dextral transpression (similar to 73 to 55 Ma), then transtension (< 55 Ma). Exhumation occurred during all three phases. During contraction, slow exhumation ( &SIM; 0.6 mm/yr) occurred along the margins of the core, driven by isostatic rebound and erosion, and faster exhumation (> 3 mm/yr) by local thrusting in regions undergoing crustal thickening. In the central part of the core (Chelan block), > 40 km of exhumation occurred between 91 and 45 Ma, about half of which occurred during early contraction ( driven by thrusting) and half during top-to-north, arc-oblique shear during reactivation of a midcrustal Cretaceous thrust, the Dinkelman decollement. The footwall of this thrust consists of the Swakane Biotite Gneiss, a Cretaceous, metaclastic assemblage with recorded pressures of 10 - 12 kbar, no arc-related magmatism, and structures dominated by pervasive top-to-north shearing. The hanging wall consists of the Napeequa Complex, an oceanic assemblage with recorded pressures of 6 12 kbar, voluminous arc-related magmatism, and complex structures indicating early top-to-WSW shearing, younger top-to-north shearing, and widespread folding. In the Napeequa, top-to-north shearing started by 73 Ma during melt-present conditions at pressures greater than or equal to6 kbar. Top-to-north shearing in both hanging wall and footwall continued during exhumation ( similar to 1.6 mm/yr) and cooling to greenschist facies conditions during which slip became increasingly localized, eventually resulting in formation of pseudotachylite on discrete slip surfaces. We suggest that arc-oblique extension was driven by along-arc heterogeneity in displacements/ erosion, initially during transpression and underplating of continental sediments, and later during transtension.

Hastings, A., R. J. Hall, et al. (2006). "A simple approach to optimal control of invasive species." Theoretical Population Biology 70(4): 431-435.

The problem of invasive species and their control is one of the most pressing applied issues in ecology today. We developed simple approaches based on linear programming for determining the optimal removal strategies of different stage or age classes for control of invasive species that are still in a density-independent phase of growth. We illustrate the application of this method to the specific example of invasive Spartina alterniflora in Willapa Bay, WA. For all such systems, linear programming shows in general that the optimal strategy in any time step is to prioritize removal of a single age or stage class. The optimal strategy adjusts which class is the focus of control through time and can be much more cost effective than prioritizing removal of the same stage class each year. (c) 2006 Elsevier Inc. All rights reserved.

Greene, C. M., D. W. Jensen, et al. (2005). "Effects of environmental conditions during stream, estuary, and ocean residency on Chinook salmon return rates in the Skagit River, Washington." Transactions of the American Fisheries Society 134(6): 1562-1581.

We predicted 22 years of return rates for wild Chinook salmon Oncorhynchus tshawytscho as a function of environmental conditions experienced during residency in freshwater, tidal delta, bay, and ocean habitats as well as as an indicator of density dependence (based on egg production) across life stages. The best predictors of return rate included the magnitude of floods experienced during incubation, a principal components factor describing environmental conditions during bay residency, a similar factor describing conditions experienced during the third ocean year, and an estimate of egg production. Our models explained up to 90% of the variation in return rate and had a very high forecasting precision, yet environmental conditions experienced during ocean residency explained only 5% of the variation. Our results suggest that returns of wild Chinook salmon can be predicted with high precision by incorporating habitat residency and that freshwater and nearshore environmental conditions strongly influence the survival of Skagit River Chinook salmon.

Greene, C. M., D. W. Jensen, et al. (2006). "Effects of environmental conditions during stream, estuary, and ocean residency on Chinook salmon return rates in the Skagit River, Washington (vol 134, pg 1562, 2005)." Transactions of the American Fisheries Society 135(2): 456-456.

Rapp, J. B., K. A. Kvenvolden, et al. (1976). "Hydrocarbons in Sediments of Willapa Bay, Washington." Transactions-American Geophysical Union 57(12): 931-931.

Smith, S. W. (1976). "Skagit Valley Earthquakes of 1974-75." Transactions-American Geophysical Union 57(2): 90-90.

Hood, W. G. (2007). "Scaling tidal channel geometry with marsh island area: A tool for habitat restoration, linked to channel formation process." Water Resources Research 43(3).

Hydraulic geometry and related analyses are often used to investigate tidal channel geometry and evolution and inform marsh restoration. An alternative approach is presented that avoids calculating tidal prism and allows analysis of additional channel metrics. It relies on scaling relationships between marsh island surface area and various metrics of the set of tidal channels draining each island. In the Skagit Delta marshes (Washington, United States), total channel surface area and length and surface area of the largest channel draining an island scaled disproportionately with island area, suggesting restoration of a 100-ha site would be preferable to restoration of 10 separate 10-ha sites to maximize channel length and area. A model of channel formation through random island conglomeration replicated observed scaling patterns, linking channel scaling to blind channel evolution from river distributaries. Channel size and complexity varied spatially, with significant deficits in an eroding marsh isolated from river distributaries and riverine sediments.

Galbraith, H., R. Jones, et al. (2002). "Global climate change and sea level rise: Potential losses of intertidal habitat for shorebirds." Waterbirds 25(2): 173-183.

Global warming is expected to result in an acceleration in Current rates of sea level rise, inundating many low-lying coastal arid intertidal areas. This could have important implications for organisms that depend on these sites, including shorebirds that rely on them for feeding habitat during their migrations and in winter. We modeled the potential changes in the extent of intertidal foraging habitat for shorebirds at five sites in the United States that currently-support internationally important numbers of migrating and wintering birds. Even assuming a conservative global warming scenario of 2degreesC within the next century (the most recent projections range between 1.4degreesC and 5.8degreesC), we project major intertidal habitat loss at four of the sites (Willapa Bay, Humboldt Bay, San Francisco Bay, arid Delaware Bay). Projected losses range between 20% and 70% of current intertidal habitat. Such losses might jeopardize the ability of these sites to continue to support their current shorebird numbers. The most Severe losses are likely to occur at sitcom where the coastline is unable to move inland because of steep topography or seawalls. The effects of sea level rise may be exacerbated by additional anthropogenic factors. In southern San Francisco Bay, for example, sea level rise may interact with land subsidence due to aquifer depletion, and the constraints imposed by existing seawalls on the landward migration of habitat, resulting in the greatest habitat loss. At the fifth site (Bolivar Flats) we project smaller losses as the intertidal habitat: are unconstrained by sea walls and will be able to migrate inland in response to rising sea level. Installation of additional coastal protection barriers at this site and others is likely to exacerbate the rate and extent of intertidal habitat loss.

Kilbride, K. M., F. L. Paveglio, et al. (1995). "Control of Smooth Cordgrass with Rodeo(R) in a Southwestern Washington Estuary." Wildlife Society Bulletin 23(3): 520-524.

We investigated efficacy of aerial and ground application of Rodeo(R) to control smooth cordgrass (Spartina alterniflora) on intertidal mudflats in Willapa Bay, Washington during 1992-1993. The herbicidal formula was applied to 2 1-ha plots using a helicopter with toe-mounted spray boom or by hand-held wand sprayer. Stem densities did not differ from pre- to post-treatment between aerially treated and control clones, Stem densities were reduced on clones where the herbicidal formulation was applied by hand, Stem density was reduced most at plots located highest in the intertidal zone, Efficacy depended on the time between treatment and subsequent tidal inundation of treated plants.