|SREL Reprint #1219|
Changes in Thermoregulation of Bluegill, Lepomis macrochirus, from
a Thermally Altered Reservoir
U. Fischer Jr., Edward A. Standora, and James R. Spotila
In the absence of a predator, small bluegill (Lepomis
macrochirus) had a mean upper avoidance temperature of 30.0°C
as compared with 29.8°C
for large bluegill. In the presence
of a predator (Micropterus salmoides), bluegill upper avoidance
temperatures were significantly higher; however, predator size did not influence
this relationship. In the presence
of a small and large bass, small bluegill had a mean upper avoidance temperature
of 34.0 and 33.9°C,
respectively, while large bluegill had a mean upper avoidance temperature of
33.8 and 33.1°C.
The preferred temperatures of large bluegill (X=26.3°C)
were statistically higher than that of small bluegill (X=25.2°C).
There was no significant difference in the preferred temperatures for
bluegill from heated and normothermic sites.
SREL Reprint #1219
Fischer, R.U., E.A. Standora, and J.R. Spotila. 1987. Predator-induced changes in thermoregulation of bluegill, Lepomis macrochirus, from a thermally altered reservoir. Canadian Journal of Fisheries and Aquatic Sciences 44:1629-1634.