Benthos Response to Disturbance in Western Lake Erie: Regional Faunal Surveys

Infauna at six stations in western Lake Erie was sampled on four occasions during 1981–1982 to determine if natural patterns of distribution and abundance reflected the response to disturbance that was revealed previously in tray colonization experiments. The distribution of opportunist species was patchy and positively associated with a gradient of bottom disturbance due to prevailing southwest winds. Distribution of late colonizers was more even and either unrelated to the gradient or more abundant in lower stress regions. Except to the extent that it covaried with bottom stress gradients, sediment grain size was not a significant predictor of benthos distribution. Small, shallow-dwelling, early colonizers appeared to suffer higher mortality during an unusually windy period (October 1981–April 1982) than the larger, deeper-dwelling, late colonizers. We suggest that a portion of the spatial and temporal variability of benthos in large, shallow lakes is probably the result of differential adaptation to a variety of bottom disturbances.