Design and test of a grid to reduce bycatch in the longfin inshore squid ( Doryteuthis pealeii ) trawl fishery

Summary A species separation grid was tested for a squid trawl to reduce finfish bycatch in the Nantucket Sound longfin inshore squid ( Doryteuthis pealeii ) fishery in southern New England, USA . The experimental trawl with a grid significantly reduces bycatch of summer flounder ( Paralichthys dentatus ) (76.4%, p  <   .001), black sea bass ( Centropristis striata ) (71.7%, p  =   .001), smooth dogfish ( Mustelus canis ) (86.0%, p  <   .001), and total bycatch (69.2%, p  <   .001) when compared to a conventional trawl. The catch rate of scup ( Stenotomus chrysops ) is 40.2% less than in the experimental trawl, but this difference is not statistically significant ( p  =   .258). However, the experimental trawl also reduces targeted squid capture by 47.5% ( p  <   .001), which is commercially unacceptable. Length analysis indicates no size effect on the retention for squid between the trawl with a grid (experimental) and the one without a grid (control), but the experimental trawl significantly reduces larger scup (>27 cm FL ) and larger black sea bass (>37 cm TL ), and all summer flounder size‐classes. Therefore, this grid design may not be a suitable bycatch reduction device for the Nantucket Sound squid trawl fishery, and further work is needed to understand squid behavior within a trawl to develop a successful bycatch reduction strategy for the New England longfin inshore squid fishery.