Grey seal

There are two recognized subspecies: The type specimen of H. g. grypus (Zoological Museum of Copenhagen specimen ZMUC M11-1525, caught in 1788 off the island of Amager, Danish part of the Baltic Sea) was believed lost for many years, but was rediscovered in 2016, and a DNA test showed it belonged to a Baltic Sea specimen rather than from Greenland, as had previously been assumed (because it was first described in Otto Fabricius' book on the animals in Greenland: Fauna Groenlandica). The name H. g. grypus was therefore transferred to the Baltic subspecies (replacing H. g. macrorhynchus), and the name H. g. atlantica resurrected for the Atlantic subspecies. Molecular studies have indicated that the eastern and western Atlantic populations have been genetically distinct for at least one million years, and could potentially be considered separate subspecies. In 2022, overlap in the range of the two subspecies was recorded for the first time. This brings the possibility that hybridisation may occur. As of 2026, no hybrids have been reported. ==Description==

, England The grey seal is large and heavy: In the eastern Atlantic, males are typically long and weigh ; the females are much smaller, typically long and in weight. Individuals from the western Atlantic are often much larger, with males averaging up to and reaching a weight of as much as and females averaging up to and sometimes weighing up to . Record-sized bull grey seals can reach about in length. A common average weight in Great Britain was found to be about for males and for females whereas in Nova Scotia, Canada, adult males averaged and adult females averaged . Colours and patterns are highly variable. Males tend to have a light pattern on a dark background, while females tend to have the opposite — a dark pattern on a light background, often with a noticeably light belly. The neck and chest of males tend to be wrinkled and scarred, while females are smoother. Males have an especially wide muzzle. Males have a large, visible opening on the lower abdomen, while females have no obvious openings. Juveniles are often a solid colour, and can be difficult or impossible to sex. Differences from other seals (left), and a grey seal (right). Note the difference in snout length Grey seals lack external ear flaps (as with their fellow earless seals), and characteristically have large snouts, often referred to as a "Roman nose". The Harbour seal occurs across the entire range of the grey seal, and they can be difficult to tell apart. Compared to the harbour seal, the grey seal has a longer, more sloped snout, a flatter head, and eyes which are set farther apart. The nostrils of the harbour seal form a "V" shape, appearing to meet at the bottom, while the nostrils of the grey seal are more parallel. The grey seal has fewer, larger spots than the harbour seal. Grey seals are often larger than harbour seals, and are about 3 times heavier. Wintering hooded seals can be confused with grey seals as they are about the same size and somewhat share a large-nosed look. They can be distinguished by the fact that the hooded seal has a paler base colour and usually evidences a stronger spotting. ==Distribution and habitat==

, UK The grey seal is resident to 18 countries: Belgium, Canada, Denmark (including Faroe Islands), Estonia, Finland, France, Germany, Iceland, Ireland, Latvia, Lithuania, the Netherlands, Norway, Poland, Russia, Sweden, the United Kingdom, and the United States of America. It is also an occasional vagrant in Greenland and Portugal. The global population was estimated to be about 632,000 in 2016. Some of the more touristically significant breeding grounds in the UK which aren't SACs include: Blakeney Point and Horsey Beach in Norfolk, various locations in Cornwall, and Donna Nook in Lincolnshire. Large numbers of grey seals have recently commenced a recolonisation of the tidal section of the River Thames in London; a survey conducted by the ZSL in 2024 found that around 3,000 grey seals were living in the area. In Ireland, the 5 largest colonies are in order: Inishkea Islands, County Mayo; various islands in Connemara, County Galway; various islands in County Donegal; Blasket Islands, County Kerry; and Saltee Islands, County Wexford. In the German Bight, colonies exist off the islands Sylt, Amrum and on Heligoland. In Iceland, the largest colony is in Breiðafjörður, with 62% of Iceland's pups being born there. Other large colonies can be found on Iceland's northwest coast, in Strandir and Skagafjörður, and the south coast, in Öræfi and Surtsey. In Canada, the grey seal is typically found in large numbers in the coastal waters of the Maritime Provinces. It is typically seen in areas such as the Gulf of St. Lawrence, Newfoundland, Prince Edward Island, and Quebec. The largest colony in the world is on Sable Island, Nova Scotia, with an estimated 76,600 pups born in 2021. In the US, it is found year-round off the coast of New England, in particular Maine and Massachusetts. There are colonies all along the northern Atlantic coast as far south as New Jersey, and occasional sightings have been reported as far as North Carolina. Archaeological evidence confirms grey seals in southern New England with remains found on Block Island, Martha's Vineyard, and near the mouth of the Quinnipiac River in New Haven, Connecticut, and there is a report by Farley Mowat of historic breeding colonies as far south as Cape Hatteras, North Carolina. Its range is expanding south, with a growing population in North Carolina. , Massachusetts, USA. Note the wide variety of colours , Norfolk ==Behaviour==

, England , Germany Grey seals spend most of their time at sea. They can be seen hauled out on rocks, islands, and shoals not far from shore, occasionally coming ashore to rest. The Baltic subspecies most frequently hauls out at night, beginning right after sunset. This may be related to the behaviour of its main prey species, Atlantic herring, which forms large schools during the day and disperses at night. Reproduction Breeding colonies are known as rookeries, and are generally on beaches and remote islands, although in the Baltic and the Gulf of St Lawrence grey seals have been known to occasionally breed on sea ice. Females generally return to the exact location where they were born to give birth, but they sometimes venture to different rookeries. The time of year that pups are born varies depending on the location, landing somewhere between September and March. The earliest pups are born in Ireland and Southwest UK in September. The time at which pups are born along the UK becomes progressively later in a counterclockwise manner; pups are born on the Isles of Scilly and Cornwall in September, in Scotland and the Farne Islands in December, and on the southeast coast in January. During lactation, the pups rapidly fatten up on their mothers' extremely fat-rich milk, quadrupling their body weight in 18 days. The milk can consist of up to 60% fat. After their fast, they leave for the sea to learn to fish for themselves. The pups are precocial, with mothers returning to the sea to forage once pups are weaned. to below 50% depending on location and conditions. Starvation due to difficulties in learning to feed appears to be the main cause of pup death. In the North Sea, multiple cases were recorded of pregnant harbour seals dying as a result of forced copulation with male grey seals. Communication While it was once thought that marine mammals communicate vocally, research conducted by researchers at Monash University shows that grey seals can clap their flippers underwater as a form of communication. This may be used to deter a predator from attacking or to attract a mate. The head researcher, Dr. Burville, had been diving for 17 years in an attempt to capture this behaviour on camera. He stated: "The discovery of 'clapping seals' might not seem that surprising, after all, they're famous for clapping in zoos and aquaria, but where zoo animals are often trained to clap for our entertainment -- these grey seals are doing it in the wild of their own accord." == Ecology ==

Diet in the Baltic Sea The grey seal feeds on a wide variety of fish, mostly benthic or demersal species, taken at depths down to 70 m (230 ft) or more. Sand eels (Ammodytes spp) are important in its diet in many localities. Cod and other gadids, flatfish, herring, wrasse and skates are also important locally. However, it is clear that the grey seal will eat whatever is available, including octopus and lobsters. The average daily food requirement is estimated to be 5 kg (11 lb), though the seal does not feed every day and it fasts during the breeding season. Observations and studies from Scotland, The Netherlands, and Germany show that grey seals will also prey and feed on large animals like harbour seals and harbour porpoises. In 2014, a male grey seal in the North Sea was documented and filmed killing and cannibalising 11 pups of his own species over the course of a week. Similar wounds on the carcasses of pups found elsewhere in the region suggest that cannibalism and infanticide may not be uncommon in grey seals. Male grey seals may engage in such behaviour potentially as a way of increasing reproductive success through access to easy prey without leaving prime territory. In 2026, a number of instances of grey seals being recorded hunting, killing and partially eating common dolphins (Delphinus delphis) off the coasts of Devon and West Wales, as well as in the Irish Sea, were recorded. It is currently not known why the seals are hunting dolphins; however, it has been theorised that the attacks may be the work of a single population or family of seals operating between North Devon and the Welsh coastline. The seals may also be shifting from hunting harbour porpoises to common dolphins due to the latter species undergoing a significant population increase, becoming the most common species of cetacean in the area where the attacks are taking place. Predators Grey seals are vulnerable to the typical predators of seals; their primary predator is the orca. Certain large species of sharks are known to prey on grey seals in North American waters, particularly great white sharks and bull sharks. Some grey seal carcasses have washed ashore with visible "cookie cutter" bite marks, a telltale sign of attack by a Greenland shark. In the waters of Great Britain, grey seals are a common prey species for orcas. In the Baltic, grey seal pups are prey for White-tailed eagles and Great black-backed gulls. ==Relationship with humans==

Hunting and culling Grey seals were nearly extirpated in the United States from hunting for oil, meat, and skins. Bounties were paid on all kinds of seals up until 1945 in Maine and 1962 in Massachusetts. In 2013, there were calls by fishermen in Cape Cod to cull the rising grey seal population, over concerns it was harming the local cod catch. In 2012, there was a controversial suggestion to cull 70,000 grey seals in the Gulf of St. Lawrence. This was spurred by predictions that the local cod population would be extirpated, with the primary cause attributed to grey seals. However, as of 2026, no such cull has taken place. In 2009, the EU banned the import and sale of seal-based products, including grey seal. As of 2026, grey seal hunting is legal in all countries on the Baltic Sea. As of 2024, about 1,500 Baltic grey seals are killed annually. Between 2019–2022, 3,774 grey seals were hunted in Sweden, making it the largest hunter of seals in the EU. In 2026, the quota for grey seals in Sweden was 1,350 — up from 1,000 the previous year. Seal hunting is not a common practice in the UK, where it is illegal to kill seals. However, licenses can be granted for culling in specific circumstances. Culling regulations in the UK as a whole are governed by the Conservation of Seals Act 1970, however each individual region can decide its own laws. In England, Wales, and Scotland, licenses to cull seals can be granted to protect flora and fauna, to reduce population surplus, and to protect public safety. In 2021, the Marine (Scotland) Act was amended, which repealed the ability to grant licenses for prevention of damage to Scottish fish farms. In Scotland, 62 grey seals were legally shot under license in 2020. In 2022, the Cornish Mackerel Fishermen group called for a cull in Cornwall, referring to grey seals as "rats of the sea". This was met with heavy backlash from marine conservation groups. Conservation and recovery , Wales After near extirpation in the United States, sightings began to increase in the late 1980s. By 2009, thousands of grey seals had taken up residence on or near popular swimming beaches on outer Cape Cod, resulting in sightings of great white sharks drawn close to shore to hunt the seals. A count of 15,756 grey seals in southeastern Massachusetts coastal waters was made in 2011 by the National Marine Fisheries Service. Grey seal populations have been expanding rapidly in the UK, likely owing to changes in food availability due to climate change. There are now an estimated 157,000 individuals in the wild. The Icelandic population was estimated to be 6,697 in 2022; this is a 27% decrease from 1982. However, population numbers have remained relatively unchanged since 2005. Seal rescue groups often take in malnourished pups abandoned by their mothers. Human noise pollution continues to affect marine-life communication but remains an understudied facet of marine conservation efforts. In more recent years, the potential negative effect of human noise has been highlighted with the discovery of seals using clapping as a form of communication. In captivity Grey seals are adaptable to life in captivity, and are commonly found as zoo animals around their native range, particularly in Europe. Grey seals need a minimum of land area and pool area with a minimum depth of . Caution needs to be taken when handling grey seals, as they are capable of delivering strong bites. Seal watching Seal watching is a popular activity, with strong economic and touristic benefits. 80,000 people are estimated to visit Horsey Beach for seal watching each year. Seals are the third biggest reason why people visit the Scottish coast for wildlife viewing. In 2003, researchers estimated the economic value of grey seal tourism in Southwest England to be £526,000 per year (). Care must be taken that seal watching does not disturb the seals. The biggest cause of seal watching related disturbance is private watercrafts. Dogs walked by seal-watchers can cause seals to stampede and suddenly enter water, where they can experience thermal shock. At Blakeney Point, which is cordoned off during pupping season, a webcam has been installed, to allow for seal watching without the possibility of disturbance. ==References==