Behavioural responses of female lake trout Salvelinus namaycush to male chemical stimuli and prostaglandin F2α.

Male olfactory cues may guide aggregation on spawning reefs, mate evaluation and synchronized gamete release in lake trout Salvelinus namaycush, but a lack of information on the source and identity of the cues precludes direct tests of their function. Using a two-channel flume, we found ovulated female lake trout increased time spent in the channel treated with spermiated male-conditioned water, urine and bile but not synthesized prostaglandin F2α . We suggest future efforts to characterize male olfactory cues focus on urine and postulate that bile acids contribute to its behavioural activity.