Evaluating the feasibility of escape mechanisms in conical snow crab traps—laboratory observations of snow crab behavior. Final report

Laboratory observations and morphometric measurements of snow crab (Chionoecetes opilio) were conducted to examine the feasi-bility of incorporating rigid escape mechanisms into conical snow crab traps to improve trap selectivity. Under laboratory conditions, undersized adolescent male snow crab (94...

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Bibliographic Details
Main Authors: Paul D. Winger, Philip J. Walsh
Other Authors: The Pennsylvania State University CiteSeerX Archives
Format: Text
Language:English
Subjects:
Online Access:http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.492.8308
http://icesjms.oxfordjournals.org/content/64/8/1587.full.pdf
Description
Summary:Laboratory observations and morphometric measurements of snow crab (Chionoecetes opilio) were conducted to examine the feasi-bility of incorporating rigid escape mechanisms into conical snow crab traps to improve trap selectivity. Under laboratory conditions, undersized adolescent male snow crab (94 mm carapace width) were capable of detecting, approaching, and interacting with escape mechanisms, and the location of the mechanisms was important in determining the likelihood of escape success. Escape mechanisms mounted low on the exterior wall of the trap received more than three times the number of penetration attempts than those mounted higher, although successful escape rates were very low. There was no difference in behaviour or escape success between traditional mesh traps and experimental wire (Aquameshw) traps fitted with escape mechanisms. Morphometric measurements suggest that an escape diameter of 95 mm would optimize the egress of small crab and prevent the loss of legal-sized crab.