The effect of substrate and cover on Perca flavescens habitat preference.

Abstract

Habitat selection is usually the trade-off between foraging benefits and predation risk costs. Especially for young and vulnerable yellow perch (Perca flavescens), avoiding predators in dangerous areas might be important even when food is abundant there. In this study, the effect of substrate and cover on young yellow perch's habitat preference was examined. Four different habitat settings were simulated; cover-open areas with dark substrate (tank 1) and light substrate (tank 2) and dark-light substrates with all-cover (tank 3) and all-open (tank 4). While in dark substrate, fish did not show any preference between cover and open area, fish preferred the cover area to the open area. In addition, fish preferred the dark substrate regardless of presence of cover. This result indicated that yellow perch avoid predation risk by using shadows created by cover and similar color with their body.