Shark species can be found in waters off Canada’s Atlantic, Pacific and Arctic coasts. Many shark populations that frequent our waters are also found off the coasts of the United States and Mexico (making them ‘transboundary’ species) and beyond to the high seas (making them ‘migratory’ species).
Of the 27 sharks most commonly found in Canadian fisheries waters, only a few are the subject of directed commercial fisheries. Others might be caught as bycatch in other fisheries, while some are known to be in our waters, but are not caught.
Sharks are typically slow growing and although their survival rate from birth is high, sharks produce few young per year. Given these characteristics, sharks are highly susceptible to overfishing and slow to recover from stock depletion. The precautionary approach to shark management and conservation is therefore very important to ensure healthy and sustainable shark populations.
Canada’s approach to the management and conservation of sharks is based on a commitment to ecological sustainability, integrated fisheries management, and the precautionary approach. This is outlined in Canada’s National Plan of Action for the Conservation and Management of Sharks. A broad array of scientific and traditional knowledge and advice is considered for shark management in Canada. This includes the regional advisory process, Committee on the Status of Endangered Wildlife in Canada assessments, and relevant stakeholder advisory committee consultations.
Internationally, Canada is committed to working with other countries to conserve and manage transboundary and migratory shark populations. This includes working through regional fisheries management organizations such as the International Commission for the Conservation of Atlantic Tunas, the Western and Central Pacific Fisheries Commission, the Inter-American Tropical Tuna Commission, and the Northwest Atlantic Fisheries Organization. These organizations support complete reporting of all shark catches, full use of shark carcasses and restrictions on shark finning, and the reduction and release of shark bycatch. Canada’s international initiatives also include working with other countries to exchange information and practical expertise.
The Porbeagle Shark
The porbeagle (Lamana nasus) is a large pelagic shark that is most often found close to the continental shelf between Newfoundland and Labrador and the Gulf of Maine. Porbeagle meat is mainly sold in Europe, while its fins are sold to Asian markets.
The porbeagle is the only shark species targeted by a directed longline fishery on Canada’s Atlantic coast. This fishery began in 1991, with annual landings of about 1,000 tonnes. Porbeagle can also be caught as bycatch in other fisheries, such as those directed at tuna, swordfish and groundfish species. Since the early 2000s, harvest limits have been reduced to allow stocks to rebuild: in 2002, the total allocated catch was reduced to 250 tonnes; and in 2006, it was reduced further to 185 tonnes (135 directed, 50 bycatch).
Knowledge about the biology and population dynamics of porbeagle shark has grown substantially over the last two decades. The Canadian longline shark and swordfish fishing industry has provided financial and in-kind support for research, including on-board collection of detailed measurements and tissues by scientific staff, as well as measurements by fishing industry members for 100 per cent of landings. Between 1998 and 2005, five stock assessment reports were published by Fisheries and Oceans Canada, and a recovery assessment report followed in 2005. Research on porbeagle shark in Atlantic Canadian waters will continue in summer of 2007, with the co-operation of the fishing industry.
The first Atlantic management plan for all shark species was implemented in 1995. This was followed by a series of improved plans, the most recent of which is the 2002-2007 integrated fisheries management plan for pelagic sharks. Through the implementation of these plans, the porbeagle population has stabilized.
Porbeagle catches reported to ICCAT (1981-2005)
The Spiny Dogfish
The spiny dogfish (squalus acanthias) is a small schooling shark that is potentially the most abundant shark species in the world. It is widely found in Canadian waters in both the Atlantic and Pacific oceans. Harvested for more than 100 years, spiny dogfish was initially used in the production of lamp oil, machine lubricant, and Vitamin A. Today, it is valued as food by a number of countries. Since the mid-1970s, for example, the Pacific dogfish fishery has supplied food to markets in Europe and Asia.
In the Pacific, local populations of spiny dogfish are found in Canadian waters around the Strait of Georgia and Puget Sound. A highly migratory population found outside the continental shelf from Alaska to Southern California also moves into coastal waters on a seasonal basis. Part of the commercial fishery in British Columbia since 1870, spiny dogfish continues to be the shark species of greatest commercial importance on the Pacific coast. Over the past five years, annual Pacific landings of dogfish have ranged between 4,000 and 5,000 tonnes, well below the total allowable catch of 11,500 tonnes.
In the Atlantic, both residential and migratory spiny dogfish populations are found in waters between Nova Scotia and North Carolina. The status of residential populations appears to be generally stable, while some migratory populations appear to be in decline. In 2002, harvesting of spiny dogfish was capped at 2,500 tonnes in order to conduct a five-year study on this species and its migratory and residential populations in Canadian Atlantic waters. The results of the study will be published in late 2007.
Within Canadian fisheries regulations, the spiny dogfish is governed by the groundfish integrated fish management plans.