Bycatch reduction in the Northeast USA directed haddock bottom trawl fishery

A simple statistical method for catch comparison studies

“…Demonstration data: the results from these previously unpublished sea trials, support the findings of US workers (Beutel et al, 2008) in that the Eliminator trawl has the potential to selectively harvest haddock and whiting in a mixed-demersal fishery while allowing cod and other species to escape. In these North Sea trials, the number of cod caught were reduced by 89% and accounted for 2% (weight) of the marketable fish caught in the Eliminator, contrasted by 10% weight in the control trawl.…”

Can we increase haddock yield within the constraints of the Magnuson–Stevens Act?

“…Jacobson and Cadrin (2008) The Ruhle trawl and Separator trawl have been each independently assessed in order to quantify their respective bycatch rates Table 1 The catchability coefficients used to model the extent of technical interactions for seven species of groundfish in the Georges Bank area for three different fishing gear types. (Beutel et al, 2006;Martins et al, 2006). We derive the catchability coefficients for each of the seven stocks (Georges Bank cod, Georges Bank haddock, Georges Bank yellowtail flounder, Cape Cod yellowtail flounder, Gulf of Maine cod, plaice and witch flounder) for the Ruhle and Separator trawls by comparing the ratio of their control trawl (conventional otter trawl) catchability with their experimental catchabilities to our control catchability (NOAA 2004 data) from the respective reports of Beutel et al (2006Beutel et al ( , 2008 and Martins et al (2006).…”

“…An illustration of the main characteristics of the three trawls described in this paper. For more detailed information on the Separator and Ruhle trawls, refer to Martins et al (2006) and Beutel et al (2006Beutel et al ( , 2008. Drawing by Rachel DeLeon.…”

“…Drawing by Rachel DeLeon. species and fragile bottom habitat (Beutel et al, 2006). The Separator trawl uses a standard otter trawl with a panel that horizontally separates the trawl into an upper and lower level, whereby the codend is attached to the upper panel while the lower panel is open allowing for bycatch species to safely pass through (Martins et al, 2006).…”

“…Both the Separator trawl and the Ruhle trawl have shown, under experimental conditions, to have higher haddock to bycatch ratios. Experimental testing of the Ruhle and Separator trawls suggest significantly lower bycatch when haddock is the target species compared to the conventional otter trawl (Beutel et al, 2006(Beutel et al, , 2008Martins et al, 2006). Although only a small portion of the Georges Bank fleet are currently using the modified trawl nets, a substantial portion of U.S. groundfish catch is allocated to an area in which only the modified trawls can be used.…”