Abstract

Turtle Excluder Devices (TEDs) are widely used in tropical shrimp trawl fisheries. TED technology was developed for shrimp trawls and its application to fish trawls is challenging due to the diversity in trawl design and gear deployment. In contrast to the local shrimp trawlers, no TED obligation currently exists for a growing fleet of demersal fish trawlers in Suriname. In this study two prototype TEDs for this fishery were evaluated. The TEDs had a vertical bar spacing of either 7 or 5 inches to ensure maximal retention of target catch. Instead of rigid aluminum bars, the TEDs were constructed from stainless steel cable and referred to as Cable TEDs (CTEDs). CTEDs are flexible which is crucial when using a drum to retrieve the trawl. The CTEDs were tested during two commercial fishing trips in 2017–2018. Twenty-five catch-comparison hauls were completed with the 7-inch CTED and 16 with the 5-inch CTED. Both CTEDs proved practical to handle on board and were easily rolled onto the ship’s net drum upon haulback. Both CTEDs caused large and significant reductions in discards. Catch rate of discards (by weight) decreased by 68 % using the 7-inch grid and by 75 % using the 5-inch grid. These reductions were mainly caused by exclusion of rays from the trawl. Ray catch rate was reduced by 79 % using the 7-inch CTED and by 94 % with the 5-inch CTED. Despite the reductions in discards, the catch of marketable fish was negatively affected by the cable grids, with significant reductions of respectively 36 % and 30 % for the 7- and 5-inch CTED. CTEDs clearly have a great potential to reduce bycatch of vulnerable species in demersal fish trawlers. Further modifications should be made and tested to improve target catch retention and make the device acceptable for the Suriname fishing industry.

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