Quantifying Juvenile Salmon Prey Quality and Exploring Trophic Linkages in Puget Sound, WA, USA

AbstractFatty acid (FA) content and composition of zooplankton in Puget Sound, Washington (USA) was studied to investigate the nutritional quality of diverse zooplankton prey for juvenile salmon (Oncorhynchus spp.) in terms of their essential fatty acid (EFA) content. The study focus was on eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and arachidonic acid (ARA) as these are key FA needed to maintain growth and development of juvenile fish. The different zooplankton taxa varied in their FA composition. Much of the variation in FA composition was driven by 18:1ω9 (a biomarker of carnivory), ARA, DHA, and FA characteristic of diatoms, which are linked to zooplankton diet sources. Gammarid and hyperiid amphipods contained the highest amount of EFA, particularly the gammarid amphipod Cyphocaris challengeri, while shrimp and copepods had much lower EFA content. Crab larvae, which are important prey for juvenile salmon in Puget Sound, had intermediate EPA + DHA content and the lowest DHA/EPA ratio, and were rich in diatom biomarkers. Temporal and spatial trends in zooplankton lipids were less apparent than the taxonomic differences, although the EFA content increased from spring to summer in Cancridae zoeae and the amphipod C. challengeri. These results on taxon-specific EFA content provide baseline information on the nutritional quality of zooplankton that can be applied in food web models. Combining zooplankton fatty acid data (quality) with taxon-specific zooplankton biomass data (quantity) enables development of new, sensitive indicators of juvenile fish production to help assess recent declines in salmon production in the Pacific Northwest and predict future adult returns.

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Biology and Management of Dogfish Sharks

Biology and Management of Dogfish Sharks ◽

10.47886/9781934874073.ch4 ◽

2009 ◽

Keyword(s):

Puget Sound ◽

Columbia River ◽

Juvenile Salmon ◽

State University ◽

Northeastern Pacific ◽

Summer Distribution ◽

National Marine Fisheries Service ◽

Columbia River Plume ◽

Oregon State University ◽

Chlorophyll Concentrations

Abstract.—Our understanding of the spiny dogfish <em>Squalus acanthias </em>of the northeastern Pacific is based almost exclusively on nearshore populations from enclosed regions (e.g., Strait of Georgia, Hecate Strait, and Puget Sound), with little attention given to more offshore populations along the open coast. Our purpose here was to characterize the summer distribution and diet of dogfish off the Washington and Oregon coasts by means of two fishery surveys: the National Marine Fisheries Service (NMFS) triennial shelf groundfish survey, 1977–2004, and the NMFS/Oregon State University juvenile salmon survey, 1998–2002. Dogfish catches were patchy throughout the entire period and showed a broad distributional range along the Washington and Oregon coasts. The highest abundances occurred in shallow waters (55–184 m) off the northern Washington and central Oregon coasts. Around the Columbia River plume, dogfish catch per unit of effort was significantly related to salinity and surface temperature patterns, but not to chlorophyll concentrations. Dogfish consumed a variety of prey, including both pelagic and benthic taxa, and with increasing size exhibited a shift in their diet to more fish and larger prey overall.

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Summary of project NR-106 activity at CVE Precommissioning School, Puget Sound Navy Yard, Bremerton, Washington. (OSRD, 1945; Publ. Bd., No. 4449.).

PsycEXTRA Dataset ◽

10.1037/e422062004-001 ◽

1946 ◽

Cited By ~ 1

Author(s):

B. J. Covner ◽

M. S. Viteles

Keyword(s):

Puget Sound

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VA Puget Sound HCS Shakes as Earth Quakes

PsycEXTRA Dataset ◽

10.1037/e511162006-007 ◽

2001 ◽

Author(s):

Joe Barison

Keyword(s):

Puget Sound

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Endangered Butterflies and their Non-Native Host Plants: Examining Shifting Values of Belonging in Restoration

Case Studies in the Environment ◽

10.1525/cse.2019.002147 ◽

2019 ◽

Vol 3 (1) ◽

pp. 1-9

Author(s):

Robert M. Anderson ◽

Amy M. Lambert

Keyword(s):

Ecological Restoration ◽

Native Species ◽

Puget Sound ◽

A Value ◽

The Social ◽

Remote Island ◽

Scientific Truth ◽

Native Host

The island marble butterfly (Euchloe ausonides insulanus), thought to be extinct throughout the 20th century until re-discovered on a single remote island in Puget Sound in 1998, has become the focus of a concerted protection effort to prevent its extinction. However, efforts to “restore” island marble habitat conflict with efforts to “restore” the prairie ecosystem where it lives, because of the butterfly’s use of a non-native “weedy” host plant. Through a case study of the island marble project, we examine the practice of ecological restoration as the enactment of particular norms that define which species are understood to belong in the place being restored. We contextualize this case study within ongoing debates over the value of “native” species, indicative of deep-seated uncertainties and anxieties about the role of human intervention to alter or manage landscapes and ecosystems, in the time commonly described as the “Anthropocene.” We interpret the question of “what plants and animals belong in a particular place?” as not a question of scientific truth, but a value-laden construct of environmental management in practice, and we argue for deeper reflexivity on the part of environmental scientists and managers about the social values that inform ecological restoration.

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