Résumé
Adult sockeye salmon (Oncorhynchus nerka, N = 179) from six Fraser River populations (British Columbia) were intercepted in continental shelf waters ∼215 km from the Fraser River mouth, gastrically implanted with acoustic transmitters, non-lethally biopsied for blood biochemistry, gill Na +,K+-ATPase activity and somatic energy density and then released. Migration behaviour and travel times to the river mouth and into the river were monitored by underwater telemetry receivers positioned at the river mouth and in the river. Post-release survival of salmon was excellent, with 84% (N = 150) of fish reaching the furthest receiving station ∼85 km upriver. Fish from Late-summer run populations (Adams and Weaver Creek) averaged a migration rate of ∼20 km day-1 through the marine area and held at the river mouth and adjacent areas for 7-9 days before entering the river. Summer-run populations (Birkenhead, Chilko, Horsefly and Stellako) had a migration rate ∼33 km day-1 and held for only 1-3 days. Once in river, similar patterns were observed: Late-run populations migrated at ∼28 km day-1 and Summer-run populations at ∼40 km day-1. From point of release to the river mouth, males migrated faster than females, but once in river migration rates did not differ between sexes. Among all females, a correlation was discovered between levels of circulating testosterone and river entry timing. This correlation was not observed among males. Plasma K+, Cl-, glucose, lactate and osmolality were also correlated with entry timing in both sexes.
Langue d'origine | English |
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Pages (de-à) | 905-918 |
Nombre de pages | 14 |
Journal | Marine Biology |
Volume | 152 |
Numéro de publication | 4 |
DOI | |
Statut de publication | Published - sept. 2007 |
Publié à l'externe | Oui |
Note bibliographique
Funding Information:Acknowledgements Many thanks are extended to M. Lapointe, J. Hills, the skipper and crew of the SunWsher, R. Alexander, L. Crossin, K. English, T. Watson and G. Wagner. Logistic support was provided by Fisheries and Oceans Canada’s Environmental Watch Program, and by the Census of Marine Life. Financial support was provided through NSERC Discovery and Strategic Grants to S.G.H., A.P.F. and G.V.D.K. G.T.C. was supported by an NSERC Canada Graduate Scholarship (CGS-D3).
ASJC Scopus Subject Areas
- Ecology, Evolution, Behavior and Systematics
- Aquatic Science
- Ecology