Photoperiod and its effect on incidence of sexual maturity in pink salmon ( Oncorhynchus gorbuscha )

Pink salmon (Oncorhynchus gorbuscha) were reared for 15 months after fry emergence under three photoperiod regimes. About 50% of males matured in a photoperiod that had two periods of declining day length within the 15-month study period. No males matured in photoperiods having only one period of de...

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Bibliographic Details
Published in:Canadian Journal of Zoology
Main Authors: Beacham, Terry D., Murray, Clyde B.
Format: Article in Journal/Newspaper
Language:English
Published: Canadian Science Publishing 1990
Subjects:
Online Access:http://dx.doi.org/10.1139/z90-180
http://www.nrcresearchpress.com/doi/pdf/10.1139/z90-180
Description
Summary:Pink salmon (Oncorhynchus gorbuscha) were reared for 15 months after fry emergence under three photoperiod regimes. About 50% of males matured in a photoperiod that had two periods of declining day length within the 15-month study period. No males matured in photoperiods having only one period of declining day length, and no females matured in any photoperiod. The rate of change of day length is likely of greater importance than the amplitude of change in inducing sexual maturation in males.