Grey Seal Facts

Grey Seals (Halichoerus Grypus) have also been heavily exploited by commercial hunts, though this trend has seen a marked decrease since the EU banned the import of Canadian seal skins in 2009. Commercial fisheries, particularly in the UK, Ireland and Canada frequently call for mass culling of Grey seals, claiming these animals are responsible for a drop in catch. These organizations ignore a mountain of evidence to the contrary and refuse to accept responsibility for their own role in the decline.

Baby Gray Seal

Grey Seal pup (Halichoerus Grypus)

BREEDING

Grey Seals are gregarious in nature and will gather together when hauling out to breed, pup and moult. The breeding season tends to vary quite considerably, depending on regional differences. In the UK for example, breeding takes place between February and April while the Canadian population breeds between December and February. Pupping may take place either on the ice or on land, again depending on regional differences.

Females usually give birth to a single pup a day or two after arriving at the rookeries. The pups weigh an average of 10-18kg and measure between 90cm and 105cm. They have a high natural mortality rate of up to 55% in the first few months of being born.

Baby Gray Seal suckling

Grey Seal nursing her pup.

The mother will nurse her pup for the first 18 days on a diet of high fat content milk. (60%fat) During this period the youngster may gain as much as 1.5kg – 2kg per day. Once the pup is fully weaned, at around 3 weeks, the mother will leave to mate with other males and leave the pup completely to fend for itself.

The pup will remain at the rookery until it has completely moulted its baby coat. During this time it survives off its blubber reserves and may actually lose a considerable amount of weight. After a period of between one and three weeks later, the pup will venture into the water to seek its own meals.

Mating can take place either on land, in the water or on the ice. Males reach sexual maturity when they are between 4-6 years but only get territorial status when they are 8-10 years old. Adult males weigh on average between 170kg – 300kg and measure approximately 1.9m to 2.5m in length. Females reach sexual maturity at 3-5years and are considerably smaller than males, weighing 100kg – 170kg and measure 1.7m – 2.1m in length. The oldest recorded female lived to 46 while the oldest male recorded lived to 29 years of age.

Female Gray seal protecting her offspring

Grey Seal protecting her baby

INTERESTING STUFF

Grey Seals are known to be illegally hunted throughout their range and, aside from entanglement issues, suffer compromised immune systems from marine pollution. They are also major victims from oil spills with Norwegian surveys showing between 40-60% of pups becoming oil fouled in their first month of life.

Pollution via organochlorines such as PCB’s and chemical pollutants such as DDT have been blamed for a large percentage of females being sterile. Reproductive failure has been reported since the 1950’s and despite measures to correct the situation, the problem still persists to this day. Studies also reflect a dramatic increase in severe stomach ulcers over the last 15 years.

Gray Seal swimming

Their scientific name, Halichoerus Grypus, means “Hooked nose sea pig.”

In 1988, signatories to the Helsinki Convention banned the hunting of this species outright in the Baltic Sea. Pressure is coming from Sweden and Finland to lift this ban despite 1997 research showing the level of sustainable hunting in the Baltic to be zero.

Gray Seals, (Halichoerus Grypus) on a rock, resting

Grey Seal sometimes spelled “Gray Seal”

Grey seals are the largest land breeding mammals in the United Kingdom. These seals are comparatively quite rare. 40% of the worlds entire population is found in the cool waters around the British Isles.

Their scientific name, Halichoerus Grypus, means “Hooked nose sea pig.” A term possibly more suited to the ministers from the DFO.

Grey Seals are also known as Gray Seals or Horse-Head Seals.

Gray seal swimming in the Baltic sea

Grey Seals are also known as Gray Seals or Horse-Head Seals.