| |
Presented at the NABS Annual meeting, Pittsburgh, Pennsylvania, 2002
in Wetlands II
TEMPERATURE-SPECIFIC GROWTH RATES OF CHIRONOMID LARVAE IN A SOUTHEASTERN U.S. WETLAND.
D.R. Holliman and A.C. Benke. Aquatic Biology Program, Department of Biological Sciences, Box 870206, University of Alabama, Tuscaloosa, Alabama 35487-0206
Experimental studies were conducted to estimate growth rates and development times for larval chironomids in a Southeastern US wetland. Growth rates were measured both under controlled conditions in the laboratory and in field microcosms. Newly hatched first instars of Chironomus sp. were used in all experiments and larvae were allowed to grow to the final instar. Growth was measured in the laboratory at 15, 20, 25, and 30°C. Larvae were fed two different food sources, TetraMin® or natural detritus, to measure the effect of food quality. Field growth rates were measured in floating aquaria with natural detritus as food. Chironomid growth rates in the laboratory were significantly correlated with temperature and were best described by a second order polynomial regression. However, growth rates were significantly lower with detrital food (0.229 d−1) than with TetraMin® (0.506 d−1). Field growth rates in the summer (0.392 d−1) were higher than detrital−reared larvae in the laboratory and less than TetraMin®−reared. Although Chironomus larvae did not reach their maximum growth rates in the field, these data suggest that growth rates in wetlands can be comparable to high growth rates, and thus high biomass turnover, found in some warm water lotic systems.
|
|
