Can Paradise Fish (Macropodus opercularis, Anabantidae) Recognize a Natural Predator? An Ethological Analysis


  • Robert Gerlai

    Corresponding author
    1. Department of Ethology, L. Eötvös University, Göd
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      Gerlai, R. 1993: Can paradise fish (Macropodus opercularis, Anabantidae) recognize a natural predator? An ethological analysis. Ethology 94, 127–136.

Mount Sinai Hospital, Research Institute, Division of Molecular Immunology and Neurobiology, 600 University Ave., Toronto, Ontario, Canada M5G 1X5.


Predator recognition and avoidance by paradise fish have been studied with allopatric species and model experiments. The effect of sympatric predators has not been investigated. Here I report that reactions of paradise fish towards a sympatric predator (Channa micropeltes) are quantitatively different from those shown towards an allopatric predator or different harmless species of fishes. I investigate the possible cues eliciting this differential response and show that visual as well as olfactory stimuli play roles. Olfactory stimuli from the sympatric predator alone elicit an elevated level of activity from paradise fish; the appearance of the sympatric predator (with or without olfactory stimuli) results in an exploratory and display reaction. I speculate what visual stimuli may play roles in predator recognition in paradise fish and I suggest that previously asserted key stimuli such as the eyes of the encountered heterospecific fish may not differentiate the harmful species from innocuous. I conclude that the antipredatory behavior of paradise fish may be affected by both genetic factors and learning and that the relative importance of the former or latter factor may vary depending on the situation.