Date of Award
5-2009
Degree Type
Thesis
Degree Name
M.S.
Degree Program
Biological Sciences
Department
Biological Sciences
Major Professor
Poirrier, Michael A.
Second Advisor
Soniat, Thomas M.
Third Advisor
DeVries, Philip J.
Abstract
Hypoxia or dissolved oxygen concentrations < 2 mg/L is a problem in estuaries worldwide. In Lake Pontchartrain, a 250 km2 de-faunated zone exists as a result of salinity stratification and episodic hypoxia. Mature common rangia clams (Rangia cuneata) are not found within this zone. Blue crabs (Callinectes sapidus) are important estuarine predators and may move in and out of the hypoxic zone to feed on hypoxia-stressed rangia clams. To test the effects of hypoxia on predation, rangia clams were exposed experimentally to severe hypoxic conditions (< 0.75 mg/l) for 72-hours and then presented to blue crabs. One hypoxic and one normoxic clam were added to each aquarium containing a blue crab for each trial, and crab feeding choices were observed and recorded. I found prey choice varied among crabs, but in general, the experimental data demonstrates that crabs chose to feed on hypoxia-stressed clams over clams kept under normoxic conditions.
Recommended Citation
Howard, Ann C., "Enhanced Blue Crab Predation on Rangia Clams after Exposure to Hypoxia" (2009). University of New Orleans Theses and Dissertations. 961.
https://scholarworks.uno.edu/td/961
Rights
The University of New Orleans and its agents retain the non-exclusive license to archive and make accessible this dissertation or thesis in whole or in part in all forms of media, now or hereafter known. The author retains all other ownership rights to the copyright of the thesis or dissertation.