Journal
CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES
Volume 65, Issue 9, Pages 1842-1866Publisher
CANADIAN SCIENCE PUBLISHING
DOI: 10.1139/F08-094
Keywords
-
Categories
Funding
- Natural Sciences and Engineering
- Research Council of Canada
- Canada Research Chairs Program
Ask authors/readers for more resources
Temporal trends in productivity of Pacific salmon (Oncorhynchus spp.) stocks are important to detect in a timely and reliable manner to permit appropriate management responses. However, detecting such trends is difficult because observation error and natural variability in survival rates tends to obscure underlying trends. A Kalman filter estimation procedure has previously been shown to be effective in such situations. We used it on a Ricker spawner-recruit model to reconstruct indices of annual productivity (recruits per spawner (R/S) at low spawner abundance) based on historical data for 120 stocks of pink (Oncorhynchus gorbuscha), chum (Oncorhynchus keta), and sockeye (Oncorhynchus nerka) salmon. These stocks were from Washington, British Columbia, and Alaska. The resulting estimated temporal trends ill productivity Show large changes (oil average 60%-70%, differences ill RIS and average ratios Of highest to lowest RIS between 5.4 and 7.9 for the three species). Such changes suggest that salmon stock assessment methods should take into account possible nonstationarity. This step will help provide scientific advice to help managers to meet conservation and management objectives. The Kalman filter results also identified some stocks that did not share temporal trend with other stocks: these exceptions may require special monitoring and management efforts.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available