|SREL Reprint #1805|
Predation-Induced Differences in Growth and Reproduction
of Bluegills (Lepomis macrochirus)
We compared growth and reproduction of bluegills (Lepomis macrochirus) in a
reservoir where fishing was not allowed (Par Pond, South Carolina) to reservoirs
that are fished. Because of intense fishing pressure, public reservoirs have
relatively low abundance and small size-structure of natural predators (e.g.,
largemouth bass). Largemouth bass (Micropterus salmoides) in Par Pond were
34 times more abundant and 10-30% larger than bass in other reservoirs in the
southeastern United States. Bluegills in Par Pond grew faster and attained larger
adult sizes than bluegills in other populations. Par Pond bluegills were about two
years older and 80 mm longer at maturity than bluegills in other southeastern
United States reservoirs. Bluegills in Par Pond began reproduction at about the
same size that they outgrew the threat of predation (about 190 mm total length).
Differences in bluegill growth and reproduction appeared largely attributable to
differences in abundance and size structure of predators in these reservoirs.
Effects of high levels of predation on growth rates and reproduction of bluegills in
this study were different from the effects of predation at low levels as studied in
SREL Reprint #1805
Belk, M.C. and L.S. Hales Jr. 1993. Predation-induced differences in growth and reproduction of bluegills (Lepomis macrochirus). Copeia 1993:1034-1044.