HR: 1330h
AN: NB33Q-13    [Abstracts]
TI: Influence of Coarse Woody Debris and Particulate Organic Matter on Density and Biomass of the Crayfish Procambarus versutus
AU: * Mitchell, R M
EM: mitchrm@auburn.edu
AF: Auburn University, Department of Biological Sciences, 331 Funchess Hall, Auburn University, AL 36849
AU: Feminella, J W
EM: jfeminel@acesag.auburn.edu
AF: Auburn University, Department of Biological Sciences, 331 Funchess Hall, Auburn University, AL 36849
AB: We estimated the density and growth of several populations of the crayfish Procambarus versutus (Cambaridae) in small sandy-bottom streams within the Southeastern Coastal Plain, at Fort Benning, Georgia. Study streams had varying levels of coarse woody debris (CWD, 4-13% of stream bottom surface) and benthic particulate organic matter (>2cm, BPOM, 1-5% of substrate). Limited work has been done to assess if CWD or BPOM, primary habitat and food resources, respectively, influence crayfish population dynamics, despite the high bioenergetic importance of crayfish in many streams. Mean monthly densities were highest in the stream with the highest %CWD and %BPOM compared with other streams; however, monthly biomass was not always highest in the high-density, high-%CWD/BPOM stream. Instead, the intermediate-%CWD stream typically had the highest crayfish biomass. This disparity may be explained by differential food quality among streams and omnivory. Benthic macroinvertebrate density and biomass both were highest in the intermediate-%CWD/POM stream, and higher macroinvertebrate biomass may have compensated for lower BPOM abundance in crayfish diets, and thus provide a better food resource for P. versutus. We are currently using stable isotope data from crayfish and potential food resources among streams to test this hypothesis.
DE: 9901 NABS Student Award - Basic Research
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly