TEMPERATURE MAGNIFIED POSTCAPTURE MORTALITY IN ADULT SABLEFISH AFTER SIMULATED TRAWLING

For sablefish Anoplopoma fimbria that had been transferred abruptly fr om ambient (5.7 degrees C) to temperatures ranging from 15 to 20 degre es C for 30 min followed by 15 min in air (19.5 degrees C), mortality increased with temperature. Mortality occurred at lower temperatures f or sablefish that were net-towed for 4 h at ambient temperature before exposure to a rapid increase in temperature. A clear relationship was apparent between serum lactate and temperature with lactate increasin g as temperature increased. For treatments in which mortality did not occur, lactate decreased sharply within 24 h, suggesting recovery. It would appear that the critical postcapture temperature for sablefish t hat reside and are captured at 4-6 degrees C, would be between 12 and 15 degrees C. The results of this study suggest that fishery managemen t strategies designed to increase postcapture survival of sablefish by catch should include a consideration of the impact of exposure to seas onal thermoclines and seasonally elevated air temperatures.