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This study investigated the impact of rope polymer type, breaking strength and diameter in relation to the injury severity of entangled baleen whales, primarily North Atlantic Right whales (Eubalaena glacialis). Fishing gear removed from live and dead entangled whales from the US East Coast and Canadian Maritimes region between 1994 and 2010 were included in this study. Average tested breaking strength of removed rope was 2,616 bs, 26% below strength at manufacture. Median rope diameter was 3/8 in. The breaking strength of ropes was significantly higher for right (4,338 mean lbs) and humpback (Megaptera novaeangliae; 3,8520 mean lbs) whales compared to smaller minke whales (Balaenoptera acutorostrata; 2,353 mean lbs). Stronger ropes (7,664 lbs) entangled adult right whales when compared to juveniles (mean 3,446 lbs) and all humpback whales (mean 3,906 lbs). Study results suggest that if ropes with breaking strengths of 1,700 lbs or less were used, the number of life-threatening whale entanglements could be reduced by at least 72%.

This is a compendium of various studies evaluating potential deterrents to large whale entanglements.

This supplement to a 2002 compendium of U.S. National Oceanographic and Atmospheric Administration (NOAA) large whale entanglement prevention research includes newer studies, including evaluation of a time tension line cutter, and studies on neutrally buoyant groundline, load cell field work on gillnets, and recycling of polypropylene rope.

This supplement to a 2002 compendium of U.S. National Oceanographic and Atmospheric Administration (NOAA) large whale entanglement prevention research has newer studies, including investigation of Seasonal Area Management (SAM) gillnet gear, gillnet weak links and anchoring systems, evaluation of gillnet weak links, and a pilot study of options for reducing vertical line entanglements.

This supplement to a 2002 compendium of U.S. National Oceanographic and Atmospheric Administration (NOAA) large whale entanglement prevention research provides an overview of recent National Marine Fisheries Service gear research and testing of the time tension line cutter.

1,700 lbf prototypes were developed and tested both in a lab and at sea to determine their fishing practicality. Use of these ropes have been documented as a strategy for reducing the incidence and severity of large whale entanglements in lobster pot buoy lines. Additionally, modeling work was carried out to assess the tensions placed on ropes when hauling gear in normal fishing operations and to evaluate what forces a whale might put on gear during an entanglement. Both lab and field testing showed the feasibility of using these ropes within near and mid-shore lobster (Homarus americanus) gear off Massachusetts.

A computer model was produced to provide insight into how the Critically Endangered North Atlantic right whale (Eubalaena glacialis, NARW) becomes entangled. It allows an anatomically accurate model of a NARW Population estimates of the critically endangered North Atlantic right whale to "swim" into fishing pot ropes, that incorporate realistic physical properties and can generate measures of physical forces (such as rope tension). Modeled entanglement events showed that those  involving the pectoral flippers with body wraps were more easily generated than entanglements involving the tailstock only. The simulator is intended as a tool for testing potential new gear configurations.

Surveys and data sources were used to investigate overlap of migrating humpback whales (Megaptera novaeangliae) and both the Western Rock Lobster Fisheries and Developmental Octopus Fisheries off the coast of Western Australia, and to investigate gear modifications to mitigate entanglement. Modifications were made to float rigs (rope type, rope length, and number of floats used), but effectiveness was not assessed within this project. Preliminary results showed that whales are more likely to become entangled in ropes that are thinner, mainlines that are yellow or orange, and orange header rigs. Acoustic pingers were also trialed, but demonstrated no impact on humpback whale behavior; however, the results were inconclusive due to environmental conditions.