Jacqueline F. Savino Robert K. Neely John E. Miller 1992 <p><span>Interspecific competition for a food resource (fish eggs) was examined in a laboratory setting between two common benthic organisms of the Great Lakes, the slimy sculpin (</span><span class="uu">Cottus cognatus</span><span>) and crayfish (</span><span class="uu">Orconectes virilis</span><span>). In monospecific tests, the median egg predation in aquarium microcosms ranged from 2.5 eggs/d for the sculpin to 3.0 eggs/d for the crayfish. In mixed-species tests, sculpin feeding rates were no different than in the monospecific tests. Feeding rates for crayfish, however, were significantly reduced by the presence of sculpin. In mixed-species treatments in which small refuges were included in the aquaria, crayfish predation of eggs was 50% less than in the monospecific tests, i.e., 1.5 eggs/d, and, crayfish went on 93% fewer excursions outside refuges, spent 94% less time outside refuges, and engaged in 83% fewer feeding bouts than sculpin (P&le; 0.05 for all comparisons). When no refuges were provided, crayfish ceased feeding (0 eggs/d). These results suggest the potential for an asymmetrical competitive interaction in a natural setting in which crayfish may be forced into a suboptimal diet by such an interaction with the slimy sculpin.</span></p> application/pdf 10.1080/02705060.1992.9664678 en Taylor & Francis Competition for food between crayfish (<i>Orconectes virilis</i>) and the slimy sculpin (<i>Cottus cognatus</i>) article