Title

Secondary sexual characters and sperm traits in coho salmon Oncorhynchus kisutch

Document Type

Article

Publication Date

2009

Publication Title

Journal of Fish Biology

Volume

74

Issue

7

First Page

1450

Last Page

1461

DOI

10.1111/j.1095-8649.2009.02210.x

Keywords

longevity, motility, sexual selection, sperm competition, sperm quality

Abstract

A study was undertaken to examine secondary sexual characters (spawning colouration and overall body size) in relation to sperm metrics in one alternative reproductive tactic of coho salmon Oncorhynchus kisutch: large hooknose males that spawn in dominance-based hierarchies. Males with less intense red spawning colouration had higher sperm velocities than males with darker red spawning colouration. There was no relationship between male body size and sperm metrics. These results suggest that within an alternative reproductive tactic, variation in sperm competition intensity may select for a trade-off between investment in sexual colouration and sperm quality.