Growth and Reproduction

Abstract

By tracking schools, growth rates of young were measured on a daily basis for several weeks. Mean length at age for the Potomac River northern snakehead was lower than fish from China, Russia, and Uzbekistan. Fish condition was above average during the spring and fall and was below average in the summer months, below average condition corresponds to periods of high spawning activity. Gonadosomatic index indicted that females begin spawning at the end of April and continue through August. Peak spawning occurs at the beginning of June when average temperatures reach 26°C. Larval fish growth rate, after transitioning to exogenous feeding was 2.3 (S.D. +/- 0.7) mm per day. Although Potomac River northern snakehead exhibit lower growth rates when compared to other populations, these fish demonstrate plasticity in timing of reproduction and rapid larval growth rates. These life history characteristics allow northern snakehead to be successful in its new environment, which is ultimately exemplified by population expansion.

Reference

Gascho Landis, A., N. W. R. Lapointe, and P. L. Angermeier. In Preparation. Growth and reproductive behavior of a newly establish population of northern snakehead, Potomac River, USA.