Fisheries Behavioral Ecology - Abstracts
Davis, M.W. 2005. Behaviour impairment in captured and released
sablefish: ecological consequences and possible substitute measures for delayed discard mortality. Journal of Fish Biology 66:254–265.
Abstract
Sablefish Anoplopoma fimbria aged 1+ and 2+ years were towed for 4 h in a net, transferred to
air for either 15 or 30 min, and then held in tanks for up to 35 days for observation of physical
injury, immediate mortality, behaviour impairment, delayed mortality and total mortality.
Behaviour was impaired for at least 3 h and returned to normal levels by 24 h after stress
induction. Behaviour impairment was correlated with delayed mortality in 2+ year fish but not
in 1+ year fish which showed greater variation in stress responses. The results of this study and
a review of past discard and escapee studies showed that substitute measures for delayed
mortality in the field should include physical injury and behaviour impairment. These two
measures integrate the effects of capture-related stressors which can produce and magnify
physical and physiological injury, resulting in changes in fish condition and delayed
mortality.
Last updated
26 April, 2007
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