Presentation Abstract
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 this region. Here, we assessed spatiotemporal patterns of several traits in hatchery-origin Chinook salmon in the Salish Sea over the last 65 years. We found that the average size at release of hatchery Chinook has increased significantly in Puget Sound, but not the Strait of Georgia. Further, it appears the average release date from hatcheries in the Puget Sound and Strait of Georgia have both converged within a common two week window. This could suggest diminished strength of the portfolio effect of hatchery subsidies on the Chinook salmon population complex in the Salish Sea. In this talk, I’ll discuss the implications these changes in hatchery practices could have for conservation of wild salmon populations, predators of salmon, and fishery production in the northeastern Pacific.
Session Title
The Salish Sea Marine Survival Project: Bottom-up and Top-down Processes
Keywords
aquaculture, Chinook salmon, hatcheries, portfolio effects, predation, size-selective, subsidies
Conference Track
SSE11: Species and Food Webs
Conference Name
Salish Sea Ecosystem Conference (2018 : Seattle, Wash.)
Document Type
Event
SSEC Identifier
SSE11-530
Start Date
6-4-2018 9:30 AM
End Date
6-4-2018 9:45 AM
Type of Presentation
Oral
Genre/Form
conference proceedings; presentations (communicative events)
Contributing Repository
Digital content made available by University Archives, Heritage Resources, Western Libraries, Western Washington University.
Subjects – Topical (LCSH)
Salmon farming--Salish Sea (B.C. and Wash.); Fish declines--Salish Sea (B.C. and Wash.); Fish hatcheries--Salish Sea (B.C. and Wash.); Fish releases--Environmental aspects--Salish Sea (B.C. and Wash.)
Geographic Coverage
Salish Sea (B.C. and Wash.)
Rights
This resource is displayed for educational purposes only and may be subject to U.S. and international copyright laws. For more information about rights or obtaining copies of this resource, please contact University Archives, Heritage Resources, Western Libraries, Western Washington University, Bellingham, WA 98225-9103, USA (360-650-7534; heritage.resources@wwu.edu) and refer to the collection name and identifier. Any materials cited must be attributed to the Salish Sea Ecosystem Conference Records, University Archives, Heritage Resources, Western Libraries, Western Washington University.
Type
Text
Language
English
Format
application/pdf
Included in
Fresh Water Studies Commons, Marine Biology Commons, Natural Resources and Conservation Commons, Terrestrial and Aquatic Ecology Commons
Changes in hatchery subsidies of Chinook salmon in the Salish Sea: implications for predators, fisheries, and conservation
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 this region. Here, we assessed spatiotemporal patterns of several traits in hatchery-origin Chinook salmon in the Salish Sea over the last 65 years. We found that the average size at release of hatchery Chinook has increased significantly in Puget Sound, but not the Strait of Georgia. Further, it appears the average release date from hatcheries in the Puget Sound and Strait of Georgia have both converged within a common two week window. This could suggest diminished strength of the portfolio effect of hatchery subsidies on the Chinook salmon population complex in the Salish Sea. In this talk, I’ll discuss the implications these changes in hatchery practices could have for conservation of wild salmon populations, predators of salmon, and fishery production in the northeastern Pacific.
