Behavioral Ecology and Sociobiology

, Volume 32, Issue 6, pp 365–370

Feeding and aggressive behaviours in juvenile coho salmon (Oncorhynchus kisutch) under chemically-mediated risk of predation

  • Guy Martel
  • Lawrence M. Dill
Article

DOI: 10.1007/BF00168819

Cite this article as:
Martel, G. & Dill, L.M. Behav Ecol Sociobiol (1993) 32: 365. doi:10.1007/BF00168819

Summary

Juvenile coho salmon (Oncorhynchus kisutch) spend the first year of their lives in their natal streams, where they may often hold feeding territories. They also face significant risk of predation by birds and fish, and should alter their behaviour to reduce risk of mortality when these predators are present. Although there is laboratory evidence that coho react to predator visual stimuli, chemoreception of avian predator presence has not previously been reported. We tested the influence of chemical stimuli of common merganser (Mergus merganser), preying on juvenile coho, on two aspects of coho territorial behaviour, foraging and aggression, in flow-through aquaria. After a mixture of merganser- and coho-conditioned water was introduced into the system, juvenile coho significantly reduced their attack distance on drifting prey. The fish also significantly decreased their aggressive behaviour directed towards mirrors (total number of acts, intensity of acts and time spent) when the same odour was present. They did not change their behaviour in either experiment after control introductions of water treated with fish alone. These results are interpreted within the framework of a trade-off between juvenile growth and mortality.

Copyright information

© Springer-Verlag 1993

Authors and Affiliations

  • Guy Martel
    • 1
  • Lawrence M. Dill
    • 1
  1. 1.Behavioural Ecology Research Group, Department of Biological SciencesSimon Fraser UniversityBurnabyCanada