Pelagic longline gear depth and shoaling
نویسندگان
چکیده
Temperature-depth recorders (TDRs) were attached to pelagic longline gear in the Hawaii-based commercial fishery to obtain actual fishing depths and to test the accuracy of catenary algorithms for predicting fishing depths. Swordfish gear was set shallow by typically deploying four hooks between successive floats. The observed depth of the settled deepest hook had a median value of 60 m for 333 swordfish sets. Tuna longline gear deployed more hooks between floats (mean = 26.8), and the observed median depth of the deepest hook was 248 m (n= 266 sets). Maximum gear depth was predicted from estimates of the longline sag ratio and catenary algorithms; however, depth was not predicted for a s s t o p a d e l t i P
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