Meeting Abstract

15.9  Wednesday, Jan. 4   Physiological responses of blue crabs, Callinectes sapidus, swimming upriver into freshwater. DEFUR, Peter L; Virginia Commonwealth University

More than 30 years ago, David Towle began a life-long series of investigations into how the crab gill functions, notably in freshwater, based on blue crabs swimming up the James River in late summer. Dr. Towle was following up on work begun by other investigators and his research led the way for numerous other investigators who pursued similar lines of research. Physiological responses of blue crabs swimming up river into fresh water include much more than ion regulation. Blue crabs also modulate the composition of the respiratory pigment and up-regulate ion transport functions. In freshwater, blue crab also encounter hypoxia and continue molting processes. Blue crabs encountering hypoxia in freshwater are able to maintain blood pH and ion transport function, stabilize oxygen uptake via a more efficient oxygen transport properties of hemocyanin.