Development and testing of an ultra-low-opening trawl to improve utilization of quota of Atlantic cod (Gadus morhua) in the groundfish fishery of New England

A team of researchers, fishermen, and a netmaker in New England developed an ultra-low-opening trawl (ULOT) with a goal to reduce catches of overfished Atlantic cod ( Gadus morhua) without loss of catches of other commercially important flatfish species. Use of the ULOT reduced catch rates of Atlantic cod by a mean of 48.0 kg/h (46.8%) compared with the use of a standard bottom trawl. It also reduced catch rates of American plaice (Hippoglossoides platessoides) by a mean of 9.5 kg/h (14.3%) but not catch rates of 3 other commercial species and 1 taxonomic group that also dominated catch. Length-based reductions in catch rates were observed, primarily for undersized American plaice (<30.5 cm in total length [TL]), mid-range yellowtail flounder (Limanda ferruginea) (36- 38 cm TL), and large witch flounder (Glyptocephalus cynoglossus) (>40 cm TL). Mean ULOT headrope height was 0.73 m, and 9.1% of fuel was saved. Economic evaluation indicated that the ULOT can increase profitability and fishing time by 53.7% and 88.1%, respectively, confirming that it is a viable option for fishermen to avoid Atlantic cod while accessing quota of more abundant groundfish species.