The effect of a single prerelease exposure to conspecific alarm cue on poststocking survival in three strains of rainbow trout (Oncorhynchus mykiss)

Canadian Journal of Zoology, e-First Articles. Significant resources go toward rearing and stocking fish globally, yet poststocking survival is often low, largely due to high predation rates on hatchery-reared fish. Antipredator behavior has been enhanced in many species through exposure to chemical cues that simulate predation events, but the implementation of such protocols may be logistically challenging. It has been suggested that a single exposure of hatchery fish to chemical cues while en route to stocking locations may be sufficient to enhance antipredator behavior and improve survival. We tested whether a one-time exposure to conspecific alarm cues while en route to a stocking site increased poststocking survival of three strains of rainbow trout (Oncorhynchus mykiss (Walbaum, 1792)). We found no difference in mortality rates between strains or between treatment fish (exposed to alarm cues) and control fish (not exposed to alarm cues), suggesting that this quick and easy protocol was insufficient and that more complex techniques should be explored to increase poststocking survival.

Source: Canadian Journal of Zoology - July 27, 2016 Category: Zoology Authors: Christopher J. Kopack E. Dale Broder Eric R. Fetherman Jesse M. Lepak Lisa M. Angeloni Source Type: research