Harp Seal
Overview
The harp seal or saddleback seal is a species of earless seal native to the northernmost Atlantic Ocean
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...

 and adjacent parts of the Arctic Ocean
Arctic Ocean
The Arctic Ocean, located in the Northern Hemisphere and mostly in the Arctic north polar region, is the smallest and shallowest of the world's five major oceanic divisions...

. It now belongs to the monotypic
Monotypic
In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...

 genus Pagophilus. Its scientific name, Pagophilus groenlandicus, means "ice-lover from Greenland", and its synonym
Synonym (taxonomy)
In scientific nomenclature, a synonym is a scientific name that is or was used for a taxon of organisms that also goes by a different scientific name. For example, Linnaeus was the first to give a scientific name to the Norway spruce, which he called Pinus abies...

, Phoca groenlandica means "Greenland seal". Originally in the genus Phoca
Phoca
Phoca is a genus of the earless seals, within the Family Phocidae. It now contains just two species, the Common Seal and the Spotted Seal...

with a number of other species, it has since been reclassified into its own genus Pagophilus.
The harp seal has a black face with silvery-gray body.
Encyclopedia
The harp seal or saddleback seal is a species of earless seal native to the northernmost Atlantic Ocean
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...

 and adjacent parts of the Arctic Ocean
Arctic Ocean
The Arctic Ocean, located in the Northern Hemisphere and mostly in the Arctic north polar region, is the smallest and shallowest of the world's five major oceanic divisions...

. It now belongs to the monotypic
Monotypic
In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...

 genus Pagophilus. Its scientific name, Pagophilus groenlandicus, means "ice-lover from Greenland", and its synonym
Synonym (taxonomy)
In scientific nomenclature, a synonym is a scientific name that is or was used for a taxon of organisms that also goes by a different scientific name. For example, Linnaeus was the first to give a scientific name to the Norway spruce, which he called Pinus abies...

, Phoca groenlandica means "Greenland seal". Originally in the genus Phoca
Phoca
Phoca is a genus of the earless seals, within the Family Phocidae. It now contains just two species, the Common Seal and the Spotted Seal...

with a number of other species, it has since been reclassified into its own genus Pagophilus.

Description

The harp seal has a black face with silvery-gray body. Its eyes are pure black. It has black harp
Harp
The harp is a multi-stringed instrument which has the plane of its strings positioned perpendicularly to the soundboard. Organologically, it is in the general category of chordophones and has its own sub category . All harps have a neck, resonator and strings...

 or wishbone
Furcula
The ' is a forked bone found in birds, formed by the fusion of the two clavicles. In birds, its function is the strengthening of the thoracic skeleton to withstand the rigors of flight....

-shaped markings on the back. They exhibit little sexual dimorphism
Sexual dimorphism
Sexual dimorphism is a phenotypic difference between males and females of the same species. Examples of such differences include differences in morphology, ornamentation, and behavior.-Examples:-Ornamentation / coloration:...

. The baby harp seal (pup) has a yellow-white coat at birth, but after three days, the coat
Coat (animal)
Coat, or the nature and quality of a show mammal's pelage, is important to the animal fancy in the judging of the animal, particularly at conformation dog shows, cat shows and horse shows...

 turns white and stays white for about 12 days. Adult harp seals grow up to be 1.7 to 2.0 m (5 to 6 feet) long and weigh from 140 to 190 kg (300 to 400 pounds).

Thermoregulation

Harp seals combine anatomical and behavioral approaches to managing their body temperatures, instead of elevating their metabolic rate and energy requirements. A thick coat of blubber
Blubber
Blubber is a thick layer of vascularized adipose tissue found under the skin of all cetaceans, pinnipeds and sirenians.-Description:Lipid-rich, collagen fiber–laced blubber comprises the hypodermis and covers the whole body, except for parts of the appendages, strongly attached to the musculature...

 insulates its body and provides energy when food is scarce or during fasting. Blubber also streamlines its body for more efficient swimming. Brown fat warms blood
Blood
Blood is a specialized bodily fluid in animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells....

 as it returns from the body surface as well as providing energy, most importantly for just-weaned pups.

Flippers
Flipper (anatomy)
A flipper is a typically flat limb evolved for movement through water. Various creatures have evolved flippers, for example penguins , cetaceans A flipper is a typically flat limb evolved for movement through water. Various creatures have evolved flippers, for example penguins (also called...

 act as heat exchangers, warming or cooling the blood as needed. On ice, the seal can press its foreflippers to its body and its hindflippers together to reduce heat loss.

Senses

Vision is its critical sense. Its eye
Eye
Eyes are organs that detect light and convert it into electro-chemical impulses in neurons. The simplest photoreceptors in conscious vision connect light to movement...

 is proportionally large and contains a large spherical lens, improving its focusing ability. Its pupil is mobile to help it adapt to the intense glare of the Arctic ice. Its retina
Retina
The vertebrate retina is a light-sensitive tissue lining the inner surface of the eye. The optics of the eye create an image of the visual world on the retina, which serves much the same function as the film in a camera. Light striking the retina initiates a cascade of chemical and electrical...

 is rod-dominated and backed by a cat-like and reflective tapetum lucidum
Tapetum lucidum
The tapetum lucidum is a layer of tissue in the eye of many vertebrate animals....

, enhancing its low light sensitivity. Its rods best sense blue-green, while its cones help with bright light and may provide some color discrimination. Its cornea
Cornea
The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber. Together with the lens, the cornea refracts light, with the cornea accounting for approximately two-thirds of the eye's total optical power. In humans, the refractive power of the cornea is...

 is constantly tear-covered, to protect it from salt
Salt
In chemistry, salts are ionic compounds that result from the neutralization reaction of an acid and a base. They are composed of cations and anions so that the product is electrically neutral...

. Lacking tear ducts, it "cries" to remove its tears. On ice, the mother identifies her offspring by smell. This sense may also warn of an approaching predator. Underwater, this seal closes its nostrils and smells nothing. Its whiskers, called vibrissae
Vibrissae
Vibrissae , or whiskers, are specialized hairs usually employed for tactile sensation. The term may also refer to the thick hairs found inside human nostrils, but these have no sensorial function and only operate as an airborne particulate barrier...

, lie in horizontal rows on either side of its snout. They may provide a touch sense, and underwater, also respond to low-frequency vibrations, such as movement.

Life history

Harp seals prefer to swim in the ocean
Ocean
An ocean is a major body of saline water, and a principal component of the hydrosphere. Approximately 71% of the Earth's surface is covered by ocean, a continuous body of water that is customarily divided into several principal oceans and smaller seas.More than half of this area is over 3,000...

, spending relatively little time on land. These are extremely social
Presociality
Presociality is a phenomenon in which animals exhibit more than just sexual interactions with members of the same species, but fall short of qualifying as eusocial...

 animals and they can be very noisy as well. They will form large colonies where they spend a great deal of time. Within that loose structure smaller groups with their own hierarchy are believed to form. Sometimes, these large groups will have to go their separate ways there. Many harp seals are able to live up to 30 years in the wild.

On the ice, pups call their mothers by "bawling" and "mumble" while playing with others. Adults "growl" and "warble" to warn off others. Underwater, adults express themselves with more than 19 call types during courting and mating.

Reproduction

Females mature sexually at age five to six. Annually thereafter, they bear one pup, usually in late February. The fertilized egg grows into a spherical embryo that implants in the uterus only after three or so months, to allow birth to take place while sufficient pack ice is available.

Newborn pups weigh around 11 kilograms (24.3 lb) and are 80 – long. After birth, the mother only feeds that pup. During the 12 day nursing period, the mother does not eat, losing up to 3 kilograms (7 lb) per day. Harp seal milk contains up to 48% fat, so pups gain over 2.2 kilograms (4.9 lb) per day. During this time, the juvenile's "greycoat" grows in beneath the white neonatal coat, and it weighs 80 pounds (36.3 kg). Weaning is abrupt; the mother turns from nursing to promiscuous mating, leaving the pup behind on the ice. While courtship
Courtship
Courtship is the period in a couple's relationship which precedes their engagement and marriage, or establishment of an agreed relationship of a more enduring kind. In courtship, a couple get to know each other and decide if there will be an engagement or other such agreement...

 starts on the ice, mating usually takes place in the water.

The stranded pup cries at first, and then becomes sedentary to conserve body fat. Within a few days, it sheds its white coat, reaching the "beater" stage.

Pups are unable to swim or find food until seven to eight weeks old or until the ice melts, leaving them vulnerable to polar bear
Polar Bear
The polar bear is a bear native largely within the Arctic Circle encompassing the Arctic Ocean, its surrounding seas and surrounding land masses. It is the world's largest land carnivore and also the largest bear, together with the omnivorous Kodiak Bear, which is approximately the same size...

s and other predators. This fast costs them up to 50% of their weight. As many as 30% of pups die during their first year, due in part to their early immobility because they learn to swim only slowly.

At about 13–14 months old, the pup molts again, becoming a "bedlamer". Juveniles molt several times, producing a "spotted harp", before the adult's harp-marked pelt fully emerges after several years (or not all in females).

Seals congregate annually on the ice to molt before migrating to summer feeding grounds. Their lifespan extends for about 20 years.

Distribution

The harp seal population is found in three separate populations, each of which uses a specific breeding site. The western North Atlantic stock, which is the largest, is located off eastern Canada
Eastern Canada
Eastern Canada is generally considered to be the region of Canada east of Manitoba, consisting of the following provinces:* New Brunswick* Newfoundland and Labrador* Nova Scotia* Ontario* Prince Edward Island* Quebec...

. This population is further divided into two separate herds based on the breeding location. The Front herd breeds off the coast
Coast
A coastline or seashore is the area where land meets the sea or ocean. A precise line that can be called a coastline cannot be determined due to the dynamic nature of tides. The term "coastal zone" can be used instead, which is a spatial zone where interaction of the sea and land processes occurs...

 of Labrador
Labrador
Labrador is the distinct, northerly region of the Canadian province of Newfoundland and Labrador. It comprises the mainland portion of the province, separated from the island of Newfoundland by the Strait of Belle Isle...

 and Newfoundland, and the Gulf herd breeds near the Magdalen Islands
Magdalen Islands
The Magdalen Islands form a small archipelago in the Gulf of Saint Lawrence with a land area of . Though closer to Prince Edward Island and Nova Scotia, the islands form part of the Canadian province of Quebec....

 in the middle of the Gulf of St. Lawrence. A second stock breeds on the "West Ice" off eastern Greenland. A third stock breeds on the "East Ice" in the White Sea
White Sea
The White Sea is a southern inlet of the Barents Sea located on the northwest coast of Russia. It is surrounded by Karelia to the west, the Kola Peninsula to the north, and the Kanin Peninsula to the northeast. The whole of the White Sea is under Russian sovereignty and considered to be part of...

, which is off the coast of Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...

. Breeding occurs between mid-February and April, and varies somewhat for each stock.

Migration and vagrancy

Harp seals are strongly migratory. The northwest population regularly moves up to 4000 kilometres (2,485.5 mi) northeast outside of the breeding season; one individual was located off the north Norwegian coast, 4640 kilometres (2,883.2 mi) east northeast of its tagging location. Their navigational accuracy is high, with good eyesight an important factor.
They are occasionally found as vagrant
Vagrancy (biology)
Vagrancy is a phenomenon in biology whereby individual animals appear well outside their normal range; individual animals which exhibit vagrancy are known as vagrants. The term accidental is sometimes also used...

s, south of their normal range. In Great Britain
Great Britain
Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...

, a total of 31 vagrants were recorded between 1800 and 1988,

More recently, they reached Lindisfarne
Lindisfarne
Lindisfarne is a tidal island off the north-east coast of England. It is also known as Holy Island and constitutes a civil parish in Northumberland...

 in Northumberland
Northumberland
Northumberland is the northernmost ceremonial county and a unitary district in North East England. For Eurostat purposes Northumberland is a NUTS 3 region and is one of three boroughs or unitary districts that comprise the "Northumberland and Tyne and Wear" NUTS 2 region...

 in September 1995, and the Shetland Islands
Shetland Islands
Shetland is a subarctic archipelago of Scotland that lies north and east of mainland Great Britain. The islands lie some to the northeast of Orkney and southeast of the Faroe Islands and form part of the division between the Atlantic Ocean to the west and the North Sea to the east. The total...

 in 1987. The latter was linked to a mass movement of harp seals into Norwegian waters; by mid-February 1987, 24,000 were reported drowned in fishing nets and perhaps 300,000 (about 10% of the world population) had invaded fjord
Fjord
Geologically, a fjord is a long, narrow inlet with steep sides or cliffs, created in a valley carved by glacial activity.-Formation:A fjord is formed when a glacier cuts a U-shaped valley by abrasion of the surrounding bedrock. Glacial melting is accompanied by rebound of Earth's crust as the ice...

s as far south as Oslo
Oslo
Oslo is a municipality, as well as the capital and most populous city in Norway. As a municipality , it was established on 1 January 1838. Founded around 1048 by King Harald III of Norway, the city was largely destroyed by fire in 1624. The city was moved under the reign of Denmark–Norway's King...

. The animals were emaciated, likely due to humans competing for their prey.

Seal hunting

All three populations are hunted commercially, mainly by Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

, Norway
Norway
Norway , officially the Kingdom of Norway, is a Nordic unitary constitutional monarchy whose territory comprises the western portion of the Scandinavian Peninsula, Jan Mayen, and the Arctic archipelago of Svalbard and Bouvet Island. Norway has a total area of and a population of about 4.9 million...

, Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...

 and Greenland
Greenland
Greenland is an autonomous country within the Kingdom of Denmark, located between the Arctic and Atlantic Oceans, east of the Canadian Arctic Archipelago. Though physiographically a part of the continent of North America, Greenland has been politically and culturally associated with Europe for...

.

In Canada, commercial hunting season is from November 15 to May 15. Most sealing occurs in late March in the Gulf of St. Lawrence, and during the first or second week of April off Newfoundland, in an area known as "the Front". This peak spring period is generally what is referred to as the "Canadian seal hunt". Hunting Canadian whitecoats has been banned since 1987. In 2006, the St. Lawrence hunt officially started on March 25 due to thin ice caused by the year's milder temperatures. Inuit
Inuit
The Inuit are a group of culturally similar indigenous peoples inhabiting the Arctic regions of Canada , Denmark , Russia and the United States . Inuit means “the people” in the Inuktitut language...

 people living in the region hunt mainly for food and, to a lesser extent, commerce.

In 2003, the three-year quota granted by the Department of Fisheries and Oceans was increased to 975,000, with a maximum of 350,000 in any two consecutive years. In 2006, 325,000 harp seals, as well as 10,000 hooded seals
Hooded Seal
The hooded seal is an arctic pinniped found only in the central and western North Atlantic ranging from Svalbard in the east to the Gulf of St...

 and 10,400 grey seal
Grey Seal
The grey seal is found on both shores of the North Atlantic Ocean. It is a large seal of the family Phocidae or "true seals". It is the only species classified in the genus Halichoerus...

s were killed. An additional 10,000 animals are allocated to First Nations
First Nations
First Nations is a term that collectively refers to various Aboriginal peoples in Canada who are neither Inuit nor Métis. There are currently over 630 recognised First Nations governments or bands spread across Canada, roughly half of which are in the provinces of Ontario and British Columbia. The...

 hunters. From 2004-2007, over 1 million were taken, 95% under the age of 3 months. Canada's total allowable catch (TAC) for 2007, was 270,000, which was higher than the sustainable yield of 165,000.

The Canadian seal hunt is monitored by the Canadian Government. Although approximately 70% of the hunt occurs on "the Front", most private monitors focus on the St. Lawrence hunt, due to its more convenient location. About 70-90,000 animals are taken from this population off the coast of Greenland.

The 2004 West Ice TAC was 15,000 "1+" animals (2 pups = 1+), almost double the sustainable catch of 8,200. Actual catches were 9,895 in 2004 and 5,808 in 2005.

The 2004 White Sea TAC was 45,000 1+ (2.5 pups = 1+). The catch was 22,474.

Therapeutic robots

Paro
Paro (robot)
Paro is a therapeutic robot baby harp seal, intended to be very cute and to have a calming effect on and elicit emotional responses in patients of hospitals and nursing homes, similar to Animal-Assisted Therapy....

is a therapeutic robot modelled on baby harp seals. It is designed to interact with people, especially those in hospitals and nursing homes. By being very cute and emotionally responsive, Paro encourages relaxation, care and other positive emotions.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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