Evaluation of variable strength hooks to reduce serious injury pilot whale interactions with the North Carolina-based pelagic longline fishery. Project 8 Final Report
The number of interactions between shortfin and longfin pilot whales Globicephala melaena and G. macrorhynchus (hereafter collectively “pilot whales”) with commercial pelagic longline fishing gear has apparently increased in recent years, especially around the southern portion of the Mid-‐Atlantic Bight (MAB) statistical area off North Carolina’s Outer Banks that was designated as the “Special Research Area” in 2006 by the Atlantic Pelagic Longline Take Reduction Team. This southern MAB area is also the primary fishing grounds for a local pelagic longline fleet operating throughout the year out of Wanchese, North Carolina, as well as seasonal fishing effort from the rest of the U.S. Atlantic fleet. If the current rates of pilot whale interactions continue, the entire U.S. Atlantic pelagic longline fishery may face more restrictive regulatory measures in these traditionally productive fishing grounds, resulting in serious economic cost to the industry. Preliminary work in 2007 and 2008 (Bayse and Kerstetter 2010) suggested that fishing hooks designed to straighten when hooked on a pilot whale might be a feasible means for reducing fisheries interactions. During 2010 and 2011, eight trips were taken aboard cooperating pelagic longline fishing vessels in the North Carolina-South Carolina offshore areas of high historical rates of interactions with pilot whales, testing two weaker (thinner wire gauge) versions of the industry-standard size 16/0 and 18/0 circle hooks. No significant reduction of target catch, target catch weight, or bycatch was observed during these trials. However, the recent imposition of a weak hook regulation in the Gulf of Mexico by the NOAA Fisheries Service for bluefin tuna bycatch reduction has resulted in an unwillingness of the local fleet to continue even limited field trials, based on the premise that similar regulations would be imposed upon the North Carolina-South Carolina offshore yellowfin tuna/swordfish pelagic longline fishery.