Bycatch mitigation actions on tropical tuna purse seiners : best practices program and bycatch releasing tools

In order to mitigate and reduce the effects of the purse seiner FAD fishery on non-target species and the marine ecosystem, the two Spanish tuna purse seiner associations (ANABAC and OPAGAC) operating in all oceanic regions, established a voluntary agreement for the application of sustainable fishing practices. The aim of this agreement is to use best fauna handling and releasing practices to maximize survival of sensitive species incidental catches (i.e., elasmobranchs and sea turtles) and prevent passive ghost fishing by using non-entangling FADs. Fishers, both officers and crew, are regularly trained in best practices and to monitor the application of these practices 100% observer coverage has been adopted by the fleet in all ocean. Observations show that most releases of large bycatches such as sharks and manta rays in tuna purse seiners are still done manually, which potentially poses a risk to crew members. Some tools such as cargo nets or stretcher beds have been used with some success to release large bycatches, but there is still much room to refine deck release equipment to maximize their survival, facilitate rapid handling and ensure fishers’ safety. The objective of the HELEA project is to develop and test new tools to release sharks and rays in tuna purse seiners that maximize their survival and are practical to use onboard. Metallic frame grids to release manta rays and manual tools like handles and specially designed fasteners will be tested to measure their efficiency for manipulating these bycatches while minimizing injury to the animals and crew. In addition, the efficiency of shark releases with and without hoppers will be evaluated.