Sub-lethal effects of disturbance on a predatory net-spinning caddisfly

Abstract

The sub-lethal effects of hydrologic disturbances on stream invertebrates are poorly understood, but integral to some models of how disturbances influence population and community dynamics. Carnivorous larvae of a net-spinning caddisfly, Plectrocnemia conspersa, have a strong predatory impact in some streams. Their silken nets, however, are vulnerable to high flow disturbance and the consequent destruction of nets could reduce predatory impacts and have life history consequences. In a laboratory experiment, we manipulated the frequency of disturbances that destroyed the nets of P. conspersa, in the presence and absence of potential prey. Animals were housed individually and each trial lasted..