Unusual Population Dynamics in Largemouth Bass, Micropterus salmoides (Lacepede), Caused by a Seasonally Fluctuating Food Supply

Publisher Website
Google Scholar
Abstract
A rare instance of massive natural mortalities among 2 yr old largemouth bass (M. salmoides was recorded in Deer Island Lake [Arizona, USA], a small backwater of the Lower Colorado River. Each spring, adult threadfin shad (Dorosoma petenense) immigrate into Deer Island Lake from the river. These shad spawn and their young temporarily increase the trophic carrying capacity for piscivorous bass. In the spring and summer of 1973, yearling (1972 yr-class) bass grew rapidly while feeding on the abundant young shad. When all sizes of shad became scarce in the autumn and winter, these bass switched to an inadequate supply of crayfish and bluegill (Lepomis macrochirus) forage. Although fry and adult shad were again abundant in the spring of 1974, they were either too small to provide acceptable forage or too large for consumption by the (now 2 yr old) bass. Rising water temperatures between May and June increased the metabolic requirements of these bass resulting in their deaths presumably from starvation.

This publication has 3 references indexed in Scilit: