Abstract

The choice of bait is one of the fisheries tactics used to increase selectivity for particular target species. The performance of three bait types (mackerel, sardine, squid) was evaluated with a commercial vessel operating in the Equatorial Atlantic Ocean using the deep-set pelagic longline deployment method to target large yellowfin and bigeye tunas. The effect of different factors and covariates on the Capture per Effort Unit - CPUE was evaluated through Generalized Linear Models (GLM). In 121 experimental sets using three bait types, 2385 individuals of the two target species were captured, 1166 yellowfin tuna and 1219 bigeye tuna. The results suggest a preference between bait types for each target species, with the yellowfin tuna being mostly caught by the hooks using squid and bigeye tuna with fish bait mackerel. Stratifying the results for three depth ranges of the hooks, the combination of bait and depth for yellowfin tuna resulted in an increase of catch probability in the intermediary depth layer using mackerel. For bigeye tuna, using mackerel in the intermediary layer resulted in a reduction in the catch rate. Bycatch represented around 11.15% of total captures. These results will provide important information to choosing the most efficient bait for the pelagic longline fishing operation and will help future decisions of fisheries management.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.