Ecological factors influencing lifetime productivity of pink salmon (Oncorhynchus gorbuscha) in an Alaskan stream

Ecological factors underlying freshwater productivity and marine survival of pink salmon (Oncorhynchus gorbuscha) were evaluated by analyzing a 30-year time series of local environmental data and censuses of migrating adult and juvenile fish collected at Auke Creek, Alaska. Freshwater productivity w...

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Bibliographic Details
Main Authors: Manhard, Christopher V., Joyce, John E., Smoker, William W., Gharrett, Anthony J.
Format: Article in Journal/Newspaper
Language:unknown
Published: NRC Research Press (a division of Canadian Science Publishing) 2016
Subjects:
Online Access:http://hdl.handle.net/1807/76846
http://www.nrcresearchpress.com/doi/abs/10.1139/cjfas-2016-0335
Description
Summary:Ecological factors underlying freshwater productivity and marine survival of pink salmon (Oncorhynchus gorbuscha) were evaluated by analyzing a 30-year time series of local environmental data and censuses of migrating adult and juvenile fish collected at Auke Creek, Alaska. Freshwater productivity was influenced primarily by spawning habitat limitation and less so by stream temperature and flow. Furthermore, a trend of declining freshwater productivity was detected over the time series, which may be related to observed declines in spawning substrate quality and in the duration of the adult migration. Marine survival was highly variable among brood years and was influenced by physical conditions in the nearshore marine environment; warm sea-surface temperatures during nearshore residency were associated with higher marine survival rates, whereas high stream flows late in the fry emigration period were associated with reduced marine survival. Simulations of adult recruitment, based on ecological factors in the freshwater and marine environments, indicated that the productivity of pink salmon in this stream is determined primarily by early marine survival. The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author.