We are pleased to announce the publication of the following paper in Conservation Biology:
Effects of fishing rope strength on the severity of large whale entanglements Amy R. Knowlton, Jooke Robbins, Scott Landry, Henry A. McKenna, Scott D. Kraus, and Timothy B. Werner The article is available open access at http://onlinelibrary.wiley.com/doi/10.1111/cobi.12590/abstract We have also developed 30 right whale case studies for the entanglements analyzed in this paper which can be found on the Consortium for Wildlife Bycatch Reduction website: http://www.bycatch.org/project/case-studies-north-atlantic-right-whale-fishing-gear-entanglements ABSTRACT Entanglement in fixed fishing gear affects whales worldwide. In the United States, deaths of North Atlantic right (Eubalaena glacialis) and humpback whales (Megaptera novaeangliae) have exceeded management limits for decades. We examined fishing gear removed from live and dead entangled whales along the U.S. East Coast and the Canadian Maritimes from 1994-2010 to determine rope polymer type, breaking strength, and diameter and compare them to entangled whales by species, age, and injury severity. For the 132 retrieved ropes from 70 cases, average tested breaking strength was range 0.80-39.63 kN, mean 11.64 kilonewtons (kN), SD 8.29 ( , which is 26% lower than strength at manufacture (range 2.89-53.38 kN, mean 15.70 kN, SD 9.89). Median rope diameter was 9.5 mm. Right and humpback whales were found in ropes with significantly stronger breaking strengths at manufacture than minke whales (19.30, 17.13 and 10.47 mean kN , respectively). Adult right whales were found in stronger ropes (mean 34.09 kN) than juvenile right whales (mean 15.33 kN) and than all humpback whale age classes (mean 17.37 kN). For right whales, severity of injuries increased since the mid-1980s, possibly due to changes in rope manufacturing in the mid-1990s that resulted in stronger ropes at the same diameter. Our results suggest that broad adoption of ropes with breaking strengths of ≤7.56 kN (≤1,700 lbsf) could reduce the number of life-threatening entanglements for large whales by at least 72% and yet could provide sufficient strength to withstand the routine forces involved in many fishing operations. A reduction of this magnitude would achieve nearly all the mitigation legally required for U.S. stocks of North Atlantic right and humpback whales. Ropes with reduced breaking strength should be developed and tested to determine the feasibility of their use in a variety of fisheries. Please contact me if any questions. best, Amy Amy Knowlton Research Scientist New England Aquarium Central Wharf Boston, MA 02110 617-973-0210 [email protected]
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