Esox americanus

The mosquitofish, Gamhusiapatruelis, avoids its predators, the chain pickerel, Esox niger, and redfin pickerel, Esox americanus, by swimming to the upper water levels. It also responds to odor from the pickerel mucus coat. This odor survives passage through filter paper and hours of bubbling but loses activity if heated or passed over charcoal (George, 1960). 

George, C. J. W. (1960). Behavioral interaction of the pickerel EsoxnigerEeSuem and Esox americanus LeSueur) and the mosquitofish Gambusiapatrudlis Bairdad Girard). Ph.D. Thesis, Harvard University Massachussetts. 

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