The capacity of benthos release panels to reduce the impacts of beam trawls on benthic communities.

Published source details Revill A.S. & Jennings S. (2005) The capacity of benthos release panels to reduce the impacts of beam trawls on benthic communities.. Fisheries Research, 73, 73-85.
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This study is summarised as evidence for the following.

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	Fit one or more mesh escape panels/windows to trawl nets Action Link

Fit one or more mesh escape panels/windows to trawl nets

A replicated, paired, controlled study in 2002–2004 in six seabed areas in the western English Channel and the North Sea, UK, Denmark, Germany, Netherlands (Revill & Jennings 2005) found that nets fitted with either one of seven designs of square mesh benthos-release panels (“bycatch reduction device”) caught less non-commercial unwanted catch of invertebrates (discard), compared to unmodified nets, and invertebrates escaping the nets had high survival rates. The two designs that reduced discards the most compared to unmodified nets consisted of 150 mm mesh with 5 mm diameter double twine (with panel: 1,988 individuals caught, without: 9,802 individuals) and 150 mm mesh with 6 mm diameter single twine (with panel: 5,286 individuals, without: 21,128 individuals). Overall survival rates (all designs combined) of escaped invertebrates were high (93–100% depending on species). In addition, five of the seven designs caught a similar amount of commercially targeted species (including the two that led to the greatest reductions in discards). These five designs reduced invertebrate discard by 48–80%. The other two designs led to 17–20% losses of target species (reductions in invertebrate discards not shown). The designs were tested on commercial beam trawls at 20–80 m depth. One trawl fitted with a panel and an unmodified trawl were towed simultaneously (4–24 tows/design). All commercial fish caught during the trials were counted and measured, and benthic invertebrates were counted and identified to species level. Invertebrates that had escaped through the panels were caught in a sled fitted to the underside of the trawl, and their survival in tanks assessed over three days.

(Summarised by: Anaëlle Lemasson & Laura Pettit)