Performance of circle hooks in a Mixed-species recreational fishery

The effects of the circle-hook on hooking injury, fish size and catch rates were evaluated for mixed-species recreational boat fisheries in the Balearic Islands (NW Mediterranean). The relationships between deep-hooking incidence (the main cause of fish mortality) and hook type (circle hooks vs conventional J-hooks), fish size, and angler were tested. Results demonstrated that the size of the fish was the most important predictor of deep-hooking incidence, as a larger fish size resulted in an increase in deeper wounds. Hook type also had a significant effect on the deep-hooking rate. Specifically, the deep-hooking rate of the most frequently-caught species, Diplodus annularis (L.) and Coris julis (L.), was reduced by greater than half with the circle hooks. The mean size of the fish caught and the unhooking time were not affected by the use of circle hooks. Finally, their use resulted in no change in the catch per unit effort (CPUE) compared to conventional hooks for both univariate and multivariate procedures. Hence, circle hooks are a promising conservation tool for marine resources when linked with catch-and-release strategies. © 2009 Blackwell Verlag, Berlin.