A team of International Seafood Sustainability Foundation (ISSF) researchers and fishers are to embark on a journey through the Pacific in search of better fishing practices as part of the ISSF Bycatch Project.
The sixth chapter of the Bycatch Project, which will take place onboard Albatun Tres, will see researchers studying the behaviour and aggregation of fish, as well as observing the behaviour of sharks and tunas inside an enclosed net. It’s all in an effort to identify techniques for freeing non-target species from fishing nets.
Most of the world’s tuna catch is made by purse seine vessels, which use a net to encircle and catch tuna. The Bycatch Project’s aim is to mitigate bycatch in the purse seine fishery and is particularly focused on operations using FADs.
In order to identify new solutions, and build off old ones, ISSF has led a series of research cruises since 2011.
This latest cruise will focus on three main points: the passive mitigation of bycatch, avoiding catch before setting and release from the net.
The passive mitigation of bycatch portion of the cruise will involve estimating species and size composition of the fish aggregation around FADs through the use of echo-sounder buoys. The objective is to inform fishers on the composition of aggregations at FADs. The aim for the fishing crew is to determine if the aggregation does not have too many small bigeye and yellowfin tunas before setting the net.
The testing of an escape panel to remove sharks and other bycatch from the net once it is set will also be undertaken. In addition, scientists will collect observational information on the behaviour of the different species of tunas and bycatch inside the net to enhance the design of the escape panel and aid in the development of additional practical modifications to prevent bycatch being brought aboard.
Assessing the survival rate of large species such as whale sharks and manta rays that are sometimes caught in the net will be the final focal area. Animals will be handled following previously identified best practices and fitted with satellite tags to monitor their behaviour and movements after they are released back into the Pacific. In this way, further improvements can be adopted where necessary to improve the chance of survival.
Information gathered during the cruises will be incorporated into new protocols, proposed equipment modifications, and best practices guides, it is also passed along to vessel owners and skippers during ISSF workshops.
