Striped Bass Hooking Mortality and Physiological Responses
Bettinger*, J.M. South Carolina Department of Natural Resources (SCDNR),
Isely, J.J. Tomasso, J.R. Clemson University, Clemson, SC.
South Carolina Cooperative
Fish and Wildlife Research
Unit, Clemson University, Clemson, SC.
Mortality and physiological responses of striped bass Morone
saxatilis caught from Lake Murray, South Carolina, and held in
live-release tubes were evaluated during spring and summer 2003.
estimate mortality, external ultrasonic transmitters were attached to 59 striped bass (average length [TL] = 585 mm).
were caught with normal fishing gear, tagged and immediately released or tagged and held in live-release tubes for 2, 4, or 6 hours and then
No mortality of striped bass was observed during spring.
Overall mortality during summer was 83%.
Mortality of summer caught striped bass was not related to tube residence time, fish total
length, depth of capture, or surface water temperature.
characterize physiological stress we measured plasma cortisol, glucose, lactate and osmolality of 62 striped bass (Average length = 563
mm) caught and immediately released or angled and held in live-release tubes.
Plasma cortisol, glucose, lactate and osmolality were positively related to tube residence time.
When the hematological characteristics were considered only in relation to tube residence time, responses characteristic of physiological
stress continued for about 150 minutes after which they began to return to normal.
Live-release tubes appear to be useful for keeping striped bass alive when they are caught from cool water, but they
are not effective when striped bass are caught from warm water.
The high summer mortality of striped bass suggests a need for restrictive fishing regulations during the summer.