Aspects of the life history of a freshwater population of the mummichog,Fundulus heteroclitus (Pisces: Cyprinodontidae), in the Bronx River,New York,U.S.A.

A freshwater population of the mummichog, Fundulus heteroclitus, was sampled during summer and autumn 1979, from the Bronx River, New York. Other occurrences in freshwater of this common estuarine cyprinodontid fish have been noted in Pennsylvania, New Hampshire and Canada. In the Bronx River, this species is a significant part of the fauna and is one of the few species found throughout the river system. Specimens were examined to determine the growth and diet. It appears that this freshwater population does not differ from its brackish water conspecifics with respect to age structure, growth rate and feeding behavior.