The effect of predation on drift rates of Stenonema (Heptagenia) in cobble substrate.

Abstract

The objectives of this experiment were to observe the effect of the crayfish on mayfly predator avoidance responses to and mayfly mortality by the sculpin predator. If the crayfish does facilitate the predation on Stenonema by sculpins, then the mortality would increase. The following hypotheses will be tested: 1. The drift rate of Stenonema will be significantly affected in the treatment with both sculpins and crayfish compared to the sculpin alone. 2. The mortality rate of Stenonema will significantly increase in the treatment with both sculpins and crayfish compared to the sculpin alone.