First published online August 8, 2003
The effect of temperature on swimming performance and oxygen consumption in adult sockeye (Oncorhynchus nerka) and coho (O. kisutch) salmon stocks
C. G. Lee1,
A. P. Farrell1,*,
A. Lotto2,
M. J. MacNutt3,
S. G. Hinch2 and
M. C. Healey4
1 Biological Sciences, Simon Fraser University, Burnaby, BC, V5A 1S6,
Canada
2 Department of Forest Sciences, University of British Columbia, Vancouver,
BC, V6T 1Z4, Canada
3 Department of Zoology, University of British Columbia, Vancouver, BC, V6T
1Z4, Canada
4 Institute for Resources and Environment, University of British Columbia,
Vancouver, BC, V6T 1Z4, Canada

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Fig. 1. Map of British Columbia, Canada illustrating the locations of fish
sampling, fish spawning and in-river hydraulic challenges to upstream
migration.
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Fig. 3. (A) Stock-specific relationships between oxygen consumption at
Ucrit
( O2max) and
water temperature t from different fish stocks (GC, Gates Creek
stock; WVR, Weaver Creek stock; CHE, Chehalis River stock; ES, Early Stuart
stock). Fish were tested at either ambient temperature (symbols without a
cross) or an adjusted temperature (symbols with a cross). The vertical lines
indicate the average ambient water temperature for each stock, which
corresponded closely with the peak
O2max for that
stock. For GC sockeye salmon:
O2max=15.26/1+[t-17.13)/8.95]2
(P<0.05; r2= 0.51). For WVR sockeye salmon:
O2max=-100.82+119.2/1+[(t-14.88)/25.52]2
(P<0.05; r2=0.59). For CHE coho salmon:
O2max=9.72/1+[(t-8.42)/7.31]2
(P<0.05; r2=0.39). (B) Stock-specific
relationships between scope for activity
( O2max- O2routine)
and water temperature from different fish stocks. The vertical lines indicate
the average ambient water temperature for each stock, which corresponded
closely with the peak
O2max for that
stock. For GC sockeye salmon: scope for
activity=11.22/1+[(t-16.63)/8.11]2 (P<0.05;
r2=0.29). For WVR sockeye salmon: scope for
activity=7.29/1+[(t-7.89)/6.03]2 (P<0.05;
r2=0.47). For CHE coho salmon: scope for
activity=8.41/1+[(t-14.48)/5.10]2 (P<0.05;
r2=0.39). (C) Relationship between
O2max and
ambient water temperature among individual fish from different stocks of
sockeye and coho salmon. The regression equation for the relationship (solid
line, P<0.05; r2=0.63) is compared with
earlier studies of adult sockeye salmon (broken line,
Davis 1966 ; dotted line,
Brett and Glass, 1973 ).
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Fig. 4. Stock-specific relationships between critical swimming speed
(Ucrit) and water temperature t among individual
fish from different fish stocks. For Gates Creek (GC) sockeye salmon:
Ucrit=2.17/1+[(t-16.15)/9.59]2
(P<0.05; r2=0.41). For Weaver Creek (WVR)
sockeye salmon:
Ucrit=1.60/1+[(t-15.18)/8.52]2
(P<0.05; r2=0.27). The relationship for
Chehalis (CHE) coho salmon was not statistically significant over the
temperature range examined. Results for Early Stuart (ES) sockeye salmon are
included for reference.
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© The Company of Biologists Ltd 2003