Biology and energetics of Tropisternus lateralis nimbatus (Coleoptera : Hydrophilidae) in a playa on the southern high plains of Texas

A study of the biology of Tropisternus lateralis nimbatus (Say), a hydrophi lid beetle, was conducted in a playa on the southern high plains of Texas f rom early June 1995 through early September 1995. Mechanism of colonization , tolerance/avoidance to drought, larval density, and secondary production were analyzed. T. lateralis colonized playas from surrounding aquatic habit ats and avoided drought through aerial dispersion. Colonization of the play a was immediate. Once in the playa, larval density increased over time. Est imated secondary production for T. lateralis in the plays was 1.86 g/m(2)/0 .25 yr with a mean standing stock biomass of 0.0819 g/m(2). The cohort prod uction interval was 14 d, resulting in an estimate of 7 discrete generation s during playa fill.