Bioenergetics

It has been hypothesized that sharks had lower metabolic rates than comparable teleosts because most of the original work on the metabolic rate of sharks focused on relatively inactive, cooler water sharks. Over time, better techniques have evolved that have allowed for the study of more active elasmobranch species that were typically considered difficult to work with in captivity. For a full review see:

Carlson, J.K, K. Goldman, and C. Lowe (2004) "Metabolism, Energetic Demands, and Endothermy" In: Biology of Sharks and Their Relatives. J.C. Carrier, J.A. Musick, M.R. Heithaus (Eds.) CRC Press, Boca Raton, FL.

Using respirometry, oxygen consumption rate is typically determined to calculate metabolic rate. However, the problems of the large size of sharks and construction of a respirometer large enough to accommodate them have limited studies on elasmobranch metabolism to the juvenile stage. The increasing sophistication and technology associated with biotelemetry likely hold promise for determining metabolism of these larger species and for bridging the gap between laboratory and field studies (Lowe, C. and K.J. Goldman. 2001. Physiological telemetry of elasmobranchs: bridging the gap. Env. Biol. Fish. 60:2251-256).

The Shark Population Assessment Group is currently employing a number of new techniques (i.e., transmitter packages capable of recording physiological and environmental data simultaneously) in an attempt to evaluate metabolic rate of free-ranging elasmobranchs. These novel techniques are being paired with classic respirometry experiments on cownose ray and bonnethead sharks. Results from previous bioenergetics studies can be found by clicking the Publications link on the right.