Seasonal Distribution and Abundance of Fishes in the Littoral Zone of a Michigan Lake

Publisher Website
Google Scholar
Abstract
The seasonal distributions and abundances of 15 littoral zone fish species were determined from May to October 1976 in a small Michigan lake. A team of divers performed seven censuses along a set of transects which encompassed nearly the entire littoral region of the lake; additional dives enabled us to determine vertical distributions and migration patterns to and from overwintering areas. All species appeared to show less habitat segregation in spring when temperatures rose and food was abundant. Species distributions and abundances were quite constant during the summer and considerable habitat segregation was apparent. The bluegill (Lepomis macrochirus) was the dominant species and was studied in greater detail. Small bluegills (<80 mm total length) were confined throughout the year to the vegetation apparently to avoid predation; larger fish moved up in the water column. This species overwintered in two localized regions of tall perennial vegetation in the deep littoral apparently in response to predation and food availability. As the water warmed to 20 C the aggregations dispersed around the entire lake; this movement was reversed in autumn. These abundances and distribution patterns appear to be stable from year to year. This is probably due to the largely perennial vegetation structure and dependable resources in this marl lake. Temperature appears to set the overall bounds to the movements and habitats utilized, but ecological interactions are probably responsible for the finer resolution of microhabitat utilization among size classes and species in the littoral zone.

This publication has 1 reference indexed in Scilit: