Abstract
Entanglement in commercial fishing gear is now considered the greatest threat to whales worldwide as well as a serious humane issue. Despite their remote arctic distribution, three bowhead stocks— Okhotsk Sea (OKH), East-Canada, West-Greenland (ECWG), and the Bering - Chukchi - Beaufort (BCB) Seas—currently overlap with commercial fishing. The northward expansion of fisheries due to sea ice reduction may eventually extend into East Greenland, Svalbard, Barents Sea (EGSB) habitat. While entanglement data are best understood for BCB bowheads, some entanglement statistics are available for the East Canada-West Greenland and Okhotsk Sea stocks as well. Three decades of whale examinations by hunters and biologists indicate that about 12% of harvested BCB bowheads show entanglement scars. Entanglement scars are far more frequent on large whales (> 17m) where about 50% exhibit scars and injuries; whales < 9m rarely show such scars (10%). Injuries associated with ship strikes are infrequent and documented on ~2% of harvested whales; body length and sex was not a significant factor but sample size is low. Continued monitoring of harvested and living bowheads (via aerial photography) is recommended to track injury rates associated with net entanglement and vessel collisions.
Published Version
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