The effect of circle hooks and J-style hooks on the catch composition, catch rates, hooking location and status of release of target and bycatch species were compared on pelagic longline vessels. There were significant differences in catch rates between the two hook types for bigeye tuna, which had higher catch rates on circle hooks and sailfish, pelagic stingrays, and leatherback sea turtles, which had higher catch rates on J-style hooks. Survival of bigeye and yellowfin tunas was significantly higher when circle hooks were used and bigeye and yellowfin tunas, swordfish and sailfish had significantly higher external hookings when circle hooks were used. The results suggests using 18/0 circle hooks with a zero degree offset could increase the survival of bycatch species while having minimal effects on the catches of target species.
Year
Journal/Publisher Name
Fisheries Research
Volume (Issue #)
107
Page #s
39-45
Contact information
hghazin@hotmail.com
Summary
Field Studies
A comparison of circle hook and J hook performance in a western equatorial Atlantic Ocean pelagic longline fishery
Study Type
Field study in the wild
Location
Equatorial Atlantic Ocean
Target catch
Tuna
Effect on bycatch species
Sailfish, pelagic stingrays, and leatherback sea turtles, had higher catch rates on J-style hooks
Effect on target catch
Bigeye and yellowfin tuna had higher survival rates when circle hooks were used
Bycatch species
Reduction technique
Fishing Gear
A comparison of circle hook and J hook performance in a western equatorial Atlantic Ocean pelagic longline fishery
Study Type
Field study in the wild
Location
Equatorial Atlantic Ocean
Target catch
Tuna
Effect on bycatch species
Catch rates were lower for leatherback sea turtles and pelagic stingrays but not sailfish when circle hooks were used
Effect on target catch
Bigeye tuna had higher catch rates when circle hooks were used
Bycatch species
Reduction technique
Fishing Gear