Entanglement poses a major threat to cetaceans worldwide
On the BC coast, the habitats of whales, dolphins and porpoises often overlap with human activities that can have harmful impacts on individual cetaceans, and populations as a whole. Entanglement in commercial fishing and aquaculture gear (both active and derelict) can cause significant injuries to whales, affecting their ability to swim and feed.
Entanglement and Humpback Whales
Entanglement in BC
The critically endangered vaquita, found only in the Gulf of Mexico, is at high risk of extinction due to bycatch and entanglement in fishing gear. It is estimated that only 30 individuals remain (photo credit: World Wildlife Fund).
Possible below-surface scenario of a humpback whale entangled around it’s pectoral fins.
With entanglements, there can be a lot going on under the surface of the water. Not only is attempting to disentangle a whale on your own increadibly dangerous, cutting only the ropes on the surfaces makes the entanglement less obvious, and greatly reduces a whale’s chance of recieving help. Call the Marine Mammal Incident Response Network immediately and stay with the whale so that it can be located easily. (Diagram: Provincetown Centre for Coastal Studies)
What can you do to help?
Clean up Debris
- IWC. (2010). Report of the workshop on welfare issues associated with the entanglement of large whales. Paper IWC/62/15 presented to the meeting of the International Whaling Commission, June 2010, Agadir, Morocco [To be published in: Journal of Cetacean Research and Management Supplement 13]. Retrieved from http://www.icmbio.gov.br/cma/images/stories/CIB__SORP/CIB/IWC_62_15.pdf
- Convention on the Conservation of Migratory species of Wild animals (UNEP/CMS)
- Nielson, J. L., Straley, J. M., Gabriele, C. M., & Hills, S. (2009). Nonlethal entanglement of humpback whales (Megaptera novaeangliae) in fishing gear in northern Southeast Alaska. Journal of Biogeography, 36(3), 452-464.
- Unpublished research, Marine Education and Research Society and Fisheries and Oceans Canada
- Groom, C., & Coughran, D. (2012). Entanglements of baleen whales off the coast of Western Australia between 1982 and 2010: patterns of occurrence, outcomes and management responses. Pacific Conservation Biology, 18(3), 203–214.
- Benjamins, S., Harnois, V., Smith, H.C.M., Johanning, L., Greenhill, L., Carter, C. &
- Wilson, B. (2014). Understanding the potential for marine megafauna entanglement risk from renewable marine energy developments. Scottish Natural Heritage Commissioned Report No. 791.
- Hall, A., Ellis, G., Trites, A.W. (2002). Harbour Porpoise Interactions with the 2001 Selective Salmon Fisheries in Southern British Columbia and License older Reported Small Cetacean By-Catch. Selective Salmon Fisheries Science Program Report. Fisheries and Oceans Canada.
- Driscoll, J., Rob, C., and Bodtker, K. (2009). Bycatch in Canada’s Pacific Groundfish Bottom Trawl Fishery: Trends and Ecosystem Perspectives. A Report by Living Oceans Society. (link)
- Cotrell, P., personal communication, September 20th, 2017.