From Abalone to Whales: Aquatic Species in Canada Face Risk of Extinction
Bowhead Whale Recovering in Canada’s Arctic
So says COSEWIC (Committee on the Status of Endangered Wildlife in Canada), which met in St. Andrews, New Brunswick, from April 25 through May 1, 2009 to assess the risk of extinction for 27 Canadian wildlife species. The Bowhead Whale is rooted deeply within Inuit culture and is the only baleen whale to reside year round in the Canadian waters of the High Arctic. Commercial whaling beginning in the 1500s severely depleted bowhead populations long before the species was given protection in the 1930s. Both Aboriginal Traditional Knowledge and scientific research provide evidence that bowhead population sizes have been steadily increasing in recent decades. As a consequence, Bowhead in the eastern Arctic were downlisted from Threatened to Special Concern, which is also the status assigned to the species in the western Arctic. Although the increased abundance is encouraging, the species faces an uncertain future in a rapidly changing Arctic climate.
Moratorium Not Enough to Halt Declines in Two Other Marine Species
American Plaice, a fish similar to sole and halibut, has suffered declines exceeding 90% in some areas along Canada's east coast. The fishery for plaice on Newfoundland's Grand Bank was once the largest fishery for flatfish in the world. Overfishing led to a moratorium on directed harvest in 1994 for the Newfoundland population, but fisheries in the Gulf of St. Lawrence and on the Scotian Shelf are still permitted. These populations were assessed as Threatened. Ongoing threats include fishing mortality caused by bycatch and under-reported catch.
The situation is even more dismal for a large marine shellfish on the Pacific Coast. Northern Abalone, prized for its succulent meat, is the only species of abalone to occur in Canada. The species continues to decline despite a 20-year moratorium on all harvest. Extensive poaching is unquestionably the primary threat to abalone. The species was up-listed from Threatened to Endangered, reflecting a heightened risk of extinction since the species was last assessed in 2000.
Wetland Species in Trouble
Canada contains one quarter of the planet’s wetlands. These extremely important ecosystems provide key habitats for a diversity of plants and animals, including migratory birds. They also act as nature’s kidneys, filtering toxins and debris from water before it is returned to major waterways. Wetlands are disappearing rapidly in some areas with a greater than 60% loss in southern Ontario and Manitoba due to agriculture and development. To date, one third of all wildlife species assessed by COSEWIC to be at risk live in or near wetlands.
Over 90% of the breeding grounds for Horned Grebe in North America are located in Canadian wetlands. Declining abundance led to a status of Special Concern for this species west of Quebec. The distinct Magdalen Islands population in Quebec, having fewer than 50 breeders, faces a higher risk of extinction and was assessed a status of Endangered.
Coastal salt marshes provide unique conditions for habitat specialists like the Maritime Ringlet. Globally this butterfly only occurs in Canada, inhabiting a few marshes in northern New Brunswick and the Gaspé Peninsula. Given its extremely limited distribution and vulnerability to habitat loss, this butterfly was assessed as Endangered.
Once ubiquitous and common in wetlands across most of Canada, the Northern Leopard Frog has experienced major declines. In BC, it only persists as a single population in the Creston valley in the south of the province. This population was designated as Endangered. Prairie and northern populations were assessed as Special Concern. Ongoing threats include spread of alien diseases and habitat loss. Populations east of Manitoba appear to be holding their own and were assessed as Not At Risk.
COSEWIC’s next scheduled wildlife species assessment meeting will be held in Ottawa, Ontario, in November 2009.
COSEWIC assesses the status of wild species, subspecies, varieties, or other important units of biological diversity, considered to be at risk in Canada. To do so, COSEWIC uses scientific, Aboriginal traditional and community knowledge provided by experts from governments, academia and other organizations. Summaries of assessments are currently available to the public on the COSEWIC website (www.cosewic.gc.ca ) and will be submitted to the Federal Minister of the Environment in late summer 2009 for listing consideration under the Species at Risk Act (SARA). At that time, the full status reports will be publicly available on the SAR Public Registry (www.sararegistry.gc.ca).
There are now 585 wildlife species in various COSEWIC risk categories, including 244 Endangered, 145 Threatened, 160 Special Concern, and 23 Extirpated wildlife species (i.e. no longer found in the wild in Canada). In addition, 13 are Extinct and 45 are Data Deficient.
COSEWIC comprises members from each provincial and territorial government wildlife agency, four federal entities (Canadian Wildlife Service, Parks Canada Agency, Fisheries and Oceans Canada, and the Federal Biodiversity Information Partnership, chaired by the Canadian Museum of Nature), three non-government science members, and the co-chairs of the Species Specialist and the Aboriginal Traditional Knowledge Subcommittees.
Definition of COSEWIC terms and risk categories:
Wildlife Species: A species, subspecies, variety, or geographically or genetically distinct population of animal, plant or other organism, other than a bacterium or virus, that is wild by nature and is either native to Canada or has extended its range into Canada without human intervention and has been present in Canada for at least 50 years.
Further details on all wildlife species assessed, and the reasons for designations, can be found on the COSEWIC website at: www.cosewic.gc.ca