Grey whale (Eschrichtius robustus) COSEWIC assessment and status report: chapter 12

Existing protection or other status and Summary of status report

Existing protection or other status

Grey whales have been protected internationally from commercial whaling since 1937. The eastern North Pacific population was listed as endangered by the International Union for Conservation of Nature and Natural Resources (IUCN) until 1996 and is now in the ‘lower risk’ category. The western North Pacific population is considered ‘critically endangered’. Grey whales are listed in Appendix 1 of the Convention on International Trade in Endangered Species (CITES), which prohibits international trade in grey whale products. The International Whaling Commission sets a subsistence catch limit for the population for member countries to partition on a bilateral basis.

Mexico has protected a large proportion of the breeding grounds of the eastern North Pacific population (see section ‘Habitat – Protection/Ownership’) and has set up guidelines for whale-watching in Mexican waters. In the United States, grey whales are protected by the Marine Mammal Protection Act, which makes it illegal to ‘harass, hunt, capture, or kill, or to attempt to harass, hunt, capture, or kill’ any marine mammal. Implementation rests with the National Marine Fisheries Service. Hunting marine mammals for native subsistence use is exempt from these regulations.

Whales in Canadian waters are managed by the federal Department of Fisheries and Oceans under the Fisheries Act and the Marine Mammal Regulations (Canadian Department of Justice 1993). These laws make it illegal to hunt or disturb cetaceans except for subsistence use, but do not protect them from bycatch or entanglement. The Department of Fisheries and Oceans has developed a set of whale-watching guidelines, which prescribe that vessels maintain a distance of at least 100 m to any cetacean (e.g. Ford et al. 2000).

Summary of status report

The eastern North Pacific population of grey whales migrates between subtropical breeding grounds off Baja California and summer feeding grounds in the Bering, Chukchi and Beaufort seas. A small portion of the population, termed the summer-resident community, spends the summer feeding in temperate waters between northern California and southeastern Alaska. The eastern North Pacific population was severely depleted by commercial exploitation in the last century. Since 1967 it has increased by approximately 2.5% annually. In 1998 the population had increased to about 26 000 individuals and was assumed to be nearing pre-exploitation levels. Since then, however, eastern Pacific grey whales have declined and are currently estimated to number around 18 000 animals. As the population approaches its historical carrying capacity, it is increasingly limited by available feeding habitat. Acoustic and chemical pollution resulting from renewed oil and gas exploration poses a potential threat to habitat off British Columbia. Feeding grounds off the Northwest Territories, and western Nunavut, are not currently threatened, but very little grey whale habitat is actually protected in Canadian waters. Effects of biotoxins and disease on the population are poorly understood.

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