Harbor seal

The harbor 'seal, also known as the common seal', is a true seal found along temperate and Arctic marine coastlines of the Northern Hemisphere. The most widely distributed species of pinniped, they are found in coastal waters of the northern Atlantic and Pacific oceans, Baltic and North seas.
Harbour seals are brown, silvery white, tan, or grey, with distinctive V-shaped nostrils. An adult can attain a length of 1.85 m and weigh up to. Blubber under the seal's skin helps to maintain body temperature. Females outlive males. Harbor seals stick to familiar resting spots or haulout sites, generally rocky areas where they are protected from adverse weather conditions and predation, near a foraging area. Males may fight over mates under water and on land. Females bear a single pup after a nine-month gestation, which they care for alone. Pups can weigh up to and are able to swim and dive within hours of birth. They develop quickly on their mothers' fat-rich milk, and are weaned after four to six weeks.
The global population of harbor seals is 350,000–500,000, but the freshwater subspecies Ungava seal in Northern Quebec is endangered. Once a common practice, sealing is now illegal in many nations within the animal's range.

Description

Individual harbor seals possess a unique pattern of spots, either dark on a light background or light on a dark. They vary in colour from brownish black to tan or grey; underparts are generally lighter. The body and flippers are short, heads are rounded. Nostrils appear distinctively V-shaped. As with other true seals, there is no pinna. An ear canal may be visible behind the eye. Including the head and flippers, they may reach an adult length of 1.85 m and a weight of 55 to 168 kg. Females are generally smaller than males.

Subspecies

The five proposed subspecies of Phoca vitulina are:

Image	Subspecies	Common name	Distribution
	P. v. vitulina	Eastern Atlantic common seal	Europe and northwestern Asia.
	P. v. concolor	Western Atlantic common seal	Inhabit eastern North America. The validity of this subspecies is questionable, and not supported by genetic evidence. They might be part of the Eastern Atlantic subspecies.
	P. v. mellonae	Ungava seal	Found in eastern Canada in fresh water
	P. v. richardii	Pacific harbor seal	Western North America.
	Phoca vitulina stejnegeri	Insular seal	Eastern Asia. Currently not recognised as a separate subspecies, but part of P. v. richardii

Population

There are an estimated 350,000–500,000 harbor seals worldwide. While the population is not threatened as a whole, the Greenland, Hokkaidō and Baltic Sea populations are exceptions. Local populations have been reduced or eliminated through disease and conflict with humans, both unintentionally and intentionally. Killing seals perceived to threaten fisheries is legal in Norway, and Canada, but commercial hunting is illegal. Seals are also taken in subsistence hunting and accidentally as bycatch. Along the Norwegian coast, bycatch accounted for 48% of pup mortality. Killing or taking seals has been illegal in the United Kingdom since 1 March 2021.
Seals in the United Kingdom are protected by the 1970 Conservation of Seals Act, which prohibits most forms of killing. In the United States, the Marine Mammal Protection Act of 1972 prohibits the killing of any marine mammals, and most local ordinances, as well as NOAA, instruct people to leave them alone unless serious danger to the seal exists.

In North America

Pacific Coast

The California population of subspecies P. v. richardii amounted to about 25,000 individuals as of 1984. Pacific harbor seals or California harbor seals are found along the entire Pacific Coast shoreline of the state. They prefer to remain relatively close to shore in subtidal and intertidal zones, and have not been seen beyond the Channel Islands as a pelagic form; moreover, they often venture into bays and estuaries and even swim up coastal rivers. They feed in shallow littoral waters on herring, flounder, hake, anchovy, codfish, and sculpin.
Breeding occurs in California from March to May, with pupping between April and May, depending on local populations. As top-level feeders in the kelp forest, harbor seals enhance species diversity and productivity. They are preyed upon by killer whales and white sharks. Haul out sites in California include urban beaches and from time to time they can be seen having a nap on the beach in all of San Francisco Bay, which would include the conurbation of Richmond, Oakland, and San Francisco, the Greater Los Angeles area, which would include Santa Barbara, the city of Los Angeles itself, and Long Beach, and all of San Diego Bay, most famously beaches near La Jolla.
Considerable scientific inquiry has been carried out by the Marine Mammal Center and other research organisations beginning in the 1980s regarding the incidence and transmission of diseases in harbor seals in the wild, including analysis of phocine herpesvirus. In San Francisco Bay, some harbor seals are fully or partially reddish in colour, possibly caused by an accumulation of trace elements such as iron or selenium in the ocean, or a change in the hair follicles.
Although some of the largest harbor seal pupping areas are found in California, they are also found north along the Pacific Coast in Oregon, Washington, British Columbia and Alaska. Large populations move with the season south along the west coast of Canada and may winter on the islands in Washington and Oregon. Pupping is known to occur in both Washington and Oregon as of 2020. People are advised to stay at least 50m away from harbor seals that have hauled out on land, especially the pups, as mothers will abandon them when there is excessive human activity nearby.

Atlantic Coast

Historically, the range of the harbor seal extended from the mouth of the St. Lawrence River and Greenland to the sandy beaches of North Carolina, a distance of well over. Evidence of their presence in these areas is consistent with both the fossil record as well as a few landmarks named after them during colonisation: Robbin's Reef, off of Bayonne, New Jersey, gets its name from the Dutch word robben, meaning "seals". On the border between Canada and the US is an island known as Machias Seal Island, a place where today the harbor seal will occasionally visit but is now a sanctuary for puffins. Over the course of hundreds of years, however, the seal was wiped out steadily by being shot on sight by fishermen and by massive pollution. The evidence for this is found in documents all along the coast of New England which put a bounty on the head of every seal shot, as well as the accounts of harbormasters. New York City, when it was founded in the 1640s, was founded on top of an enormous estuary teeming with life that included the harbor seal. Oil in the 1800s started the process of pollution that was later compounded by even more toxic 20th century chemicals that included PCB's and dioxin. By the time of the 1972 Clean Water Act, New York Harbor was almost dead-almost no living thing could survive in it. Approximately to the north, Boston Harbor was equally polluted. Raw sewage had been dumped in the harbor since the late 1800s and the stench of faecal matter in the Charles River was overpowering, as evidenced by the song "Dirty Water" by the Standells, written in 1966. Flatfish, abundant in the area, had enormous tumors in their livers by the 1980s and the harbor seal was long gone, shot to oblivion.
As of 2020, however, the seals have returned. They never were extirpated from Canada and certain pockets of the Maine coast, and thus an important mother population was created from whence the species could reclaim the home of their ancestors. Currently, they are sighted as far south as the barrier islands of North Carolina on a regular basis, with Massachusetts being the southernmost point of known pupping areas along the Atlantic Coast. Harbor seals move south from eastern Canadian waters to breed along the coast of Maine, Cape Cod, and the South Shore in Massachusetts in May and June, and return northward in fall. Others will head south from these areas to "vacation" in warmer waters, particularly young seals unable to compete with adults for food and territory; they do not return north until spring.
One park ranger in New York City, which is in the centre of its West Atlantic range, says that "New York is like their Miami resort". This refers to the habit of young seals leaving Cape Cod and even some Arctic waters to inhabit the harbor in winter. In 2018 the New York Post reported that the harbor is now "cleaner than it has been in 110 years", and since the first decade of the 21st century, the harbor seal has found the old turf of its ancestors to be a land of plenty and the water to be livable. Within sight of the New York skyline, known colonies of harbor seals are found on Hoffman and Swinburne Islands as well as portions of Red Hook and Staten Island, readily hauling out every from October until very early May. Known favourite foods of the seal are returning in grand numbers to New York Harbor as well as nearby New Jersey, from Raritan Bay all the way down the entire Jersey Shore, with schools of mossbunker regularly attracting harbor seals, their cousins the grey seals, dolphins and, most recently, whales. Both the northern and southern shores of Long Island have a reliable population of harbor seals as well as greys, where they will take sand lance as well as some species of crab as part of their diet.