순천 상내리 갯골에 출현하는 민물두줄망둑(Tridentiger bifasciatus)의 식성

Abstract

The feeding habits of Tridentiger bifasciatus were studied using 733 individuals collected in the tidal creek at Sangnae-ri, Suncheon, Korea, using a push net, monthly, from April 2011 to March 2012. The standard length (SL) of the specimens ranged from 1.5 to 8.2 cm. The stomach content analysis indicated that T. bifasciatus con- sumed mainly amphipods, such as Corophium sp., while copepods, polychaetes, and shrimps were other im- portant prey species. In addition T. bifasciatus ate small quantities of crab larvae, fish, gastropod larvae, and in- sects. T. bifasciatus is a generalist that feeds on various zoobenthos, including fish. T. bifasciatus underwent an ontogenetic dietary shift. Smaller individuals (1-2 cm SL) fed mainly on amphipods. The proportion of amphi- pods decreased as body size increased, whereas the consumption of polychaetes increased gradually. The sea- sonal variation in the diet composition of T. bifasciatus was significant. Insects were common prey during sum- mer, while the amounts of other prey, including polychaetes, were similar during spring, autumn, and winter.