Protandry in Pacific salmon

Protandry, the earlier arrival of males to the spawning grounds than females, has been reported in several studies of Pacific salmon (Oncorhynchus spp.). However, the reasons for protandry in salmon are poorly understood and little is known about how protandry varies among and within populations. In...

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Bibliographic Details
Published in:Canadian Journal of Fisheries and Aquatic Sciences
Main Author: Morbey, Yolanda
Format: Article in Journal/Newspaper
Language:English
Published: Canadian Science Publishing 2000
Subjects:
Online Access:http://dx.doi.org/10.1139/f00-064
http://www.nrcresearchpress.com/doi/pdf/10.1139/f00-064
Description
Summary:Protandry, the earlier arrival of males to the spawning grounds than females, has been reported in several studies of Pacific salmon (Oncorhynchus spp.). However, the reasons for protandry in salmon are poorly understood and little is known about how protandry varies among and within populations. In this study, protandry was quantified in a total of 105 years using gender-specific timing data from seven populations (one for pink salmon (O. gorbuscha), three for coho salmon (O. kisutch), two for sockeye salmon (O. nerka), and one for chinook salmon (O. tshawytscha)). Using a novel statistical procedure, protandry was found to be significant in 90% of the years and in all populations. Protandry may be part of the males' strategy to maximize mating opportunities and may facilitate mate choice by females.