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A Characterization Of Hyporheic Temperatures With Applications For Salmon Habitat Restoration In A Thermally Impaired River, Sydney Jantsch
A Characterization Of Hyporheic Temperatures With Applications For Salmon Habitat Restoration In A Thermally Impaired River, Sydney Jantsch
WWU Graduate School Collection
This thesis project is part of an ongoing study assessing the effectiveness of a potentially innovative habitat restoration strategy for Pacific salmon in thermally impaired rivers. This strategy uses engineered log jams (ELJs) to create pockets of cool-water refuge by forming deep scour pools and promoting localized upwellings of shallow subsurface (i.e., hyporheic) water. This project seeks to characterize the relationship between hyporheic temperature and overlying surface stream temperature to elucidate the extent to which hyporheic upwellings can deliver cool water to ELJ-formed pools during the summer low-flow season. Among six sites within a 2.7 km-long study reach on the …
Visual Characteristics Of Walleye Pollock And Chinook Salmon: Modeling Theoretical Visual Space And Target Contrast Of Trawling Materials In The Bering Sea, Rebecca Haehn
WWU Graduate School Collection
Walleye pollock (Gadus chalcogrammus) and Chinook salmon (Oncorhynchus tshawytscha) are economic and cultural resources in Alaska. Chinook salmon bycatch is a large concern within the pollock fishery. Current strategies to reduce salmon bycatch include modifying trawl gear by implementing artificial light near or on escapement panels to increase salmon escapement. The visual characteristics of pollock and Chinook salmon were investigated to understand the perception of trawl gear. The visual pigments of each species were measured using microspectrophotometry (MSP). Pollock were dichromats with spectral sensitivity ranging from 449nm–518 nm and Chinook salmon were trichromats with sensitivity ranging …
Changes In Hatchery Subsidies Of Chinook Salmon In The Salish Sea: Implications For Predators, Fisheries, And Conservation, Benjamin Nelson, Eric John Ward, Ole Shelton, Joseph H. Anderson
Changes In Hatchery Subsidies Of Chinook Salmon In The Salish Sea: Implications For Predators, Fisheries, And Conservation, Benjamin Nelson, Eric John Ward, Ole Shelton, Joseph H. Anderson
Salish Sea Ecosystem Conference
Historically, salmon hatcheries were designed to increase fishery production and to recover depleted native populations. As demands of human protein consumption increase and wild populations continue to decline due to anthropogenic impacts like climate change and habitat loss, hatcheries and stocking programs will be called on to provide food security and to supplement threatened populations. Since 1950 over 3.7 billion Chinook salmon have been released into the Salish Sea and its tributaries in Washington State and southern British Columbia. However, relatively little research has been conducted that considers the impact of hatchery subsidies on estuarine and nearshore marine ecosystems in …
High-Resolution Archival Tags Provide New Insights Into The Underwater Foraging And Echolocation Behavior Of Resident Killer Whales Capturing Pacific Salmon, Brianna Wright
Salish Sea Ecosystem Conference
Dtags contain sensors for recording both high resolution animal movement and underwater sound. They provide a valuable tool for examining the foraging behavior of resident killer whales, a specialist predator that relies on echolocation to find and pursue Pacific salmon, its primary prey. We deployed Dtags on 32 northern residents off Vancouver Island, BC, and compared reconstructed whale dive paths to distributions of different salmonid prey. Foraging whales dove deeper, remained submerged longer, swam faster, increased their dive path tortuosity, and rolled their bodies more than during other activities. Foraging dive structure also reflected the deeper vertical distribution of Chinook …
Evaluating Common Trends In Chinook Density And The Influence Of Temperature And Salinity Patterns Among Distributary Channels In A Large River Estuary To Aid Evaluation, Planning, And Prioritization Of Restoration Activities, Joshua Chamberlin, Jason E. Hall, Todd Zackey, Frank Leonetti, Michael Rustay
Evaluating Common Trends In Chinook Density And The Influence Of Temperature And Salinity Patterns Among Distributary Channels In A Large River Estuary To Aid Evaluation, Planning, And Prioritization Of Restoration Activities, Joshua Chamberlin, Jason E. Hall, Todd Zackey, Frank Leonetti, Michael Rustay
Salish Sea Ecosystem Conference
Landscape context is critical in estuary restoration planning and assessment due to the complexity and size of estuaries, and the unique attributes and cumulative effects of individual restoration projects. In addition, the diversity and mobility of estuarine species, in particular juvenile salmon, highlights the importance of landscape position given certain locations in the delta are less accessible to salmon. The Snohomish River delta has been the focus of major estuary restoration efforts in recent years and efforts could result in the largest cumulative estuary restoration action in Puget Sound. While several large projects have been initiated/competed in recent years, information …
Density-Dependent And Landscape Effects Upon Estuary Rearing In Chinook Salmon: Insights From Long-Term Monitoring In Four Puget Sound Estuaries, Correigh M. Greene, Eric M. Beamer, Rich Henderson, Joshua Chamberlin, Jason Hall, Joseph H. Anderson, Matthew Pouley, Melanie Davis, Sayre Hodgson, Christopher Ellings
Density-Dependent And Landscape Effects Upon Estuary Rearing In Chinook Salmon: Insights From Long-Term Monitoring In Four Puget Sound Estuaries, Correigh M. Greene, Eric M. Beamer, Rich Henderson, Joshua Chamberlin, Jason Hall, Joseph H. Anderson, Matthew Pouley, Melanie Davis, Sayre Hodgson, Christopher Ellings
Salish Sea Ecosystem Conference
Juvenile Chinook salmon are well known for utilizing estuarine habitats within the tidal delta for rearing during outmigration. Several studies have linked population responses to availability of estuary habitat, and support the hypothesis that estuarine habitats are vital rearing areas for juvenile Chinook salmon. However, these coarse-scale studies provide little insight on how specific estuarine habitats contribute to rearing potential for salmon. We integrate long-term monitoring data from four estuaries of Puget Sound (Nooksack, Skagit, Snohomish, and Nisqually) to examine whether 1) Chinook populations in these rivers are limited by restricted estuary habitat, 2) hatchery releases can influence density dependent …
Southern Resident Killer Whales: From Captivity To Conservation, Colleen Weiler, Rob Lott, Erich Hoyt, Deborah Giles, Howard Garrett, Susan Berta, Rein Attemann, Giulia Good-Stefani, Francine Kershaw
Southern Resident Killer Whales: From Captivity To Conservation, Colleen Weiler, Rob Lott, Erich Hoyt, Deborah Giles, Howard Garrett, Susan Berta, Rein Attemann, Giulia Good-Stefani, Francine Kershaw
Salish Sea Ecosystem Conference
The endangered Southern Resident killer whale (Orcinus orca) (SRKW) population remains the only killer whale population listed under the United States Endangered Species Act in U.S. waters since it was listed in 2005. In the 1960s and 70s, the population was reduced by approximately 40% following intensive efforts to capture individuals for a growing marine park captivity industry. The first Northwest killer whale census (1974) found just 70 remaining individuals in the SRKW community. This population has struggled to return to pre-capture numbers, and in the face of new threats including prey depletion, toxic contamination, and vessel effects, fewer than …
The Ecosystem Approach: Recovering Rivers To Help Save The Southern Resident Killer Whales, Colleen Weiler, Deborah Giles, Regina Asmutis-Silvia
The Ecosystem Approach: Recovering Rivers To Help Save The Southern Resident Killer Whales, Colleen Weiler, Deborah Giles, Regina Asmutis-Silvia
Salish Sea Ecosystem Conference
The “ecosystem approach” to managing habitats is of growing interest in the world of conservation biology, with the realization that recovery of protected species ultimately relies on the health of their environment. In the case of the critically endangered Southern Resident Killer Whale (SRKW) population, prey depletion is a major threat to their survival. Research has shown that the SRKWs are highly dependent on Chinook salmon; thus the restoration of Chinook throughout the U.S. and Canada Pacific region is crucial for SRKW recovery. The significant decline of salmon abundance can be attributed to habitat loss and degradation throughout their range. …
Competing Tradeoff Between Increasing Marine Mammal Predation And Fisheries Harvest Of Chinook Salmon, Brandon E. Chasco, Isaac C. Kaplan, Austen C. Thomas, Alejandro Acevedo-Gutiérrez, Dawn P. Noren, Michael J. Ford, M. Bradley Hanson, Jonathan J. Scordino, Steven J. Jeffries, Kristin N. Marshall, Andrew O. Shelton, Craig Matkin, Brian J. Burke, Eric J. Ward
Competing Tradeoff Between Increasing Marine Mammal Predation And Fisheries Harvest Of Chinook Salmon, Brandon E. Chasco, Isaac C. Kaplan, Austen C. Thomas, Alejandro Acevedo-Gutiérrez, Dawn P. Noren, Michael J. Ford, M. Bradley Hanson, Jonathan J. Scordino, Steven J. Jeffries, Kristin N. Marshall, Andrew O. Shelton, Craig Matkin, Brian J. Burke, Eric J. Ward
Biology Faculty and Staff Publications
Many marine mammal predators, particularly pinnipeds, have increased in abundance in recent decades, generating new challenges for balancing human uses with recovery goals via ecosystem-based management. We used a spatio-temporal bioenergetics model of the Northeast Pacific Ocean to quantify how predation by three species of pinnipeds and killer whales (Orcinus orca) on Chinook salmon (Oncorhynchus tshawytscha) has changed since the 1970s along the west coast of North America, and compare these estimates to salmon fisheries. We find that from 1975 to 2015, biomass of Chinook salmon consumed by pinnipeds and killer whales increased from 6,100 to …