Size: Male grey seals may reach a length of 2.3 m in length and weigh as much as 350 kg. Females are smaller, reaching 2 m in length and weigh up to 227 kg.
Feeding habits and impact on the ecosystem: Grey seals feeds on a wide variety of fish including cod, white hake, flatfish, herring, skate, octopus and lobster.
DFO has conducted extensive scientific research, in collaboration with independent scientific experts and the fishing industry, to improve our understanding of the complex relationships between grey seals and other components of the Atlantic coastal ecosystem, including Atlantic cod.
While much research remains to be done, the lack of cod recovery in the southern Gulf of St. Lawrence appears to be due to high mortality among larger cod. Predation by grey seals may account for up to 50 percent of this natural mortality, making them a major factor limiting the recovery of this cod stock. The Department continues to study the interaction between grey seals in Quebec and Atlantic Canada and this information will be used to inform management of both the seal harvest and the cod fishery.
Reproduction and life cycle: Grey seal pups are born from late December to early February in the western Atlantic. During their two week nursing period, pups double their weight reaching approximately 50 kg at weaning. Within their first month, they shed their white coat, grow dense waterproof adult fur, and soon leave for the sea to learn to fish for themselves.
Lifespan: 30 to 40 years
Distribution: Grey seals are found on both shores of the North Atlantic Ocean. In Canada they are found in the Gulf of St. Lawrence off the shores of Quebec, New Brunswick, Prince Edward Island, Nova Scotia and Newfoundland.
Population trends: The grey seal population has risen steadily over the last three decades. The total estimated grey seal population size in 2014 (including pups) was estimated to be 505,000 animals. Grey seals in the Northwest Atlantic form a single population. However, they are usually separated into three herds for management purposes based on the location of breeding sites. The three herds are referred to as Sable Island, coastal Nova Scotia and Gulf of St. Lawrence. The Sable Island herd has increased rapidly from approximately 1,300 animals in 1960 to an estimated 394,000 animals in 2014. In the gulf, the population has grown more slowly due to higher mortality among young animals associated with breeding on the pack ice, as well as a greater number of removals from the population. The gulf population has increased from approximately 5,000 animals in 1960 to an estimated 98,000 animals in 2014. Fewer animals are associated with the coastal Nova Scotia herd. In this area total numbers have increased from approximately 1,000 in 1960, to an estimated 14,000 in 2014.
Conservation status in Canada: The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) designated grey seals ‘Not at Risk’ in April 1999.
Source: Fisheries & Oceans Canada