Life history of the endangered vermilion darter (etheostoma chermocki) endemic to the black warrior river system, alabama

Abstract

The endangered vermilion darter (Etheostoma chermocki) is endemic to the Black Warrior River system, Mobile Basin, Alabama. Collections of specimens obtained from October 1969 to January 2000 were evaluated to determine life history characteristics. Standard length was significantly correlated with body mass, gonad mass, and clutch size. Sex ratio (2:1) was in favor of females. Length frequency distribution and enumeration of otolith annuli revealed four different age classes (0 to 3). Vermilion darters matured at the end of the first year of life. Gonadosomatic index indicated reproduction occurred from March to June. Mean clutch size was 65 oocytes per female, and mean oocyte diameter was 1.14 mm. The vermilion darter is a generalist benthic invertivore, predominantly consuming larval chironomids, tipulids, and hydropsychids. Diet breadth was greatest during warmer months and least during colder months. © 2005, Copyright Taylor & Francis Group, LLC.