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Overview

Brief Summary

The Greenland shark is an inhabitant of the deep North Pole seas. However every once in a while, it is seen in Dutch waters. Greenland shark meat is toxic and can only be consumed when prepared in a special way. The skin of this shark is used to bind books. Greenland sharks are omnivores. Scientists have found the strangest food items it their stomachs, such as reindeer, dogs, cats and even a polar beer. These animals were probably already dead when the shark consumed them.
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Comprehensive Description

Biology

Found on continental and insular shelves and upper slopes down to at least 1,200 m (Ref. 247) and to as deep as 2,200 m (Ref. 55584). Epibenthic-pelagic (Ref. 58426). In the Arctic and boreal Atlantic, it occurs inshore in the intertidal and at the surface in shallow bays and river mouths during colder months, retreating to depths of 180-550 m when the temperature rises (Ref. 247). Feeds on pelagic and bottom fishes (herring, Atlantic salmon, Arctic char, capelin, redfish, sculpins, lumpfish, cod, haddock, Atlantic halibut, Greenland halibut and skates (Ref. 5951)), sharks and skates (Ref. 5578), seals and small cetaceans, sea birds, squids, crabs, amphipods, marine snails, brittle stars, sea urchins, and jellyfish (Ref. 247, 58240). Petromyzon marinus was reported to have been attached to S. microcephalus (Ref. 58185). Ovoviviparous (Ref. 205). Also utilized fresh and dried for human and sled-dog food (flesh is said to be toxic when fresh); eskimos also used the skin to make boots, and the sharp lower dental bands as knives for cutting hair (Ref. 247). A very sluggish shark (Ref. 28609).
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Distribution

Greenland, Davis Strait to Eastport, Maine
  • North-West Atlantic Ocean species (NWARMS)
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Range Description

Restricted to Northern Atlantic and Artic regions. Reports of S. microcephalus from the Southern Hemisphere are S. antarcticus.
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Arctic and North Atlantic.
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Geographic Range

Somniosus pacificus is found in the north Atlantic, from the coast of New England and Canada to Scandinavian waters. They occasionally venture as far south as the mouth of the Seine River in France.

Biogeographic Regions: atlantic ocean (Native )

  • Compagno, L. 1984. FAO Species Catalogue Volume 4:Sharks of the World. Rome: United Nations Development Programme.
  • Compagno, L., S. Fowler. 2005. Sharks of the World. Princeton, New Jersey: Princeton University Press.
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occurs (regularly, as a native taxon) in multiple nations

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National Distribution

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

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Arctic Ocean; North Atlantic (including western Baltic Sea, northern North Sea).
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Northern Atlantic, from Polar latitudes south to the North Sea and accidentally to the mouth of the Seine and perhaps to Portugal. In the east; south to Newfoundland and the northern part of the Gulf of St. Lawrence in the west, and less commonly to the Gulf of Maine. It is represented in the Mediterranean region, in the North Pacific, and in the sub-Antarctic by forms that appear to be closely allied to this species.
  • Bigelow, H. B. and Schroeder, W. C., 1953; Compagno, L. J. V., 1984; Compagno, L. J. V., D. A. Ebert and M. J. Smale, 1989.
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Physical Description

Morphology

Dorsal spines (total): 0; Dorsal soft rays (total): 0; Analspines: 0; Analsoft rays: 0; Vertebrae: 41 - 44
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Physical Description

Somniosus pacificus is a large, sluggish shark that averages between 2 and 4 meters in length. Most of the body is a medium grey or brown in color and sometimes exhibits dark transverse bands or small spots or blotches that are lighter or darker than the base color. The snout is short and rounded, and the body is heavy and cylindrical in shape with small precaudal fins. No spines are present in the two equally-sized dorsal fins, and the ventral lobe of the caudal fin is slightly elongated. No anal fin is present. The skin is quite rough, exhibiting denticles with curved pointed cusps. Teeth in the upper and lower jaws differ in shape; upper teeth are spear-shaped while the lower teeth are shaped with high roots and low bent cusps for slicing.

Range mass: 700 to 1000 kg.

Range length: 40 to 640 cm.

Average length: 244 to 427 cm.

Other Physical Features: ectothermic ; heterothermic ; bilateral symmetry

Sexual Dimorphism: female larger; sexes shaped differently

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Size

Maximum size: 7300 mm TL
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Max. size

730 cm TL (male/unsexed; (Ref. 247)); max. published weight: 775.0 kg (Ref. 4699)
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to 730.0 cm TL; max.weight: 775 kg .
  • Bigelow, H. B. and Schroeder, W. C., 1953; Compagno, L. J. V., 1984; Compagno, L. J. V., D. A. Ebert and M. J. Smale, 1989.
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Diagnostic Description

A gigantic, heavily-bodied dogfish shark with a moderately long, rounded snout and small, low dorsal fins; lower caudal lobe long; upper jaw with small single-cusped teeth and lower jaw with moderate-sized, bent-cusped, slicing teeth (Ref. 5578). Medium grey or brown in color, sometimes with transverse dark bands or small light spots (Ref. 5578).
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Ecology

Habitat

nektonic
  • North-West Atlantic Ocean species (NWARMS)
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Cool northern seas; found near the surface of estuaries, shallow bays and coastal waters during winter and cooler waters to 600m in summer.
  • North-West Atlantic Ocean species (NWARMS)
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Habitat and Ecology

Habitat and Ecology
Littoral and epibenthic, ranging from river mouths and bays to continental shelf and slope waters. Usually found in depths of 0 to 1,200 m, but one shark was observed at 2,200 m off North Carolina (Herdendorf and Berra 1995, Compagno in prep. a). During winter months in the Arctic and boreal Atlantic, the species occurs in the intertidal zone and at the surface in shallow bays and river mouths, moving into depths of 180 to 550 m during warmer months. At lower latitudes (Gulf of Maine and North Sea) the species occurs on the continental shelves with possible movements into shallower water during spring and summer (Compagno in prep. a). Short term tracking studies of the Greenland sharks under ice off Baffin Island during late Spring suggest that individuals remained at deeper depths during the morning, gradually moving into shallower depths in the afternoon and at night (Skomal and Benz 2004). The species has been recorded in water temperatures of 0.6 to 12°C (Compagno in prep. a).

Maximum size is uncertain, but is at least 640 cm TL, possibly to 730 cm TL, however most adults are between 244 and 427 cm TL (Compagno in prep. a). Aplacental viviparous with one observed female carrying 10 young (Compagno in prep. a). Tagging studies have shown the species to be very slow growing with medium size sharks appearing to grow at a rate of 1 cm per year (Hansen 1957, Castro 1983, Castro et al. 1999).

Although reportedly sluggish, feeds on a variety of prey including invertebrates, fish, seabirds, seals as well as offal (see Compagno in prep. a for more details).

Life history parameters
Age at maturity (years): Unknown.
Size at maturity (total length cm): Unknown.
Longevity (years): Unknown.
Maximum size (total length): 640?730 cm TL.
Size at birth: ~37 to 38 cm TL (Bjerkan and Koefoed 1957, Compagno in prep. a).
Average reproductive age (years): Unknown.
Gestation time (months): Unknown.
Reproductive periodicity: Unknown.
Average annual fecundity or litter size: 10.
Annual rate of population increase: Unknown.
Natural mortality: Unknown.

Systems
  • Marine
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Environment

benthopelagic; brackish; marine; depth range 0 - 2200 m (Ref. 247), usually 200 - 600 m (Ref. 35388)
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Somniosus pacificus live mainly on continental and insular shelves. They occupy intertidal regions in addition to some river mouths and shallow bay areas during the winter months and often move to depths from 180 to 550 meters during warmer months. They have been observed as low as 1200 meters, with one observation at 2200 meters off the coast of Georgia - extending its range both geographically and in terms of depth. In northern parts of their range, Greenland sharks are found from 0 to 1200 meters in waters from 1 to 12 degrees Celsius. In southern parts of their range, these sharks may occur at greater depths.

Range depth: 145 to 1200 m.

Average depth: 180-550 m.

Habitat Regions: temperate ; polar ; saltwater or marine

Aquatic Biomes: pelagic ; coastal

Other Habitat Features: estuarine ; intertidal or littoral

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Depth range based on 26 specimens in 1 taxon.
Water temperature and chemistry ranges based on 16 samples.

Environmental ranges
  Depth range (m): 46 - 3100
  Temperature range (°C): 2.024 - 8.732
  Nitrate (umol/L): 13.189 - 31.290
  Salinity (PPS): 34.055 - 35.501
  Oxygen (ml/l): 4.022 - 6.389
  Phosphate (umol/l): 0.923 - 2.511
  Silicate (umol/l): 7.726 - 48.790

Graphical representation

Depth range (m): 46 - 3100

Temperature range (°C): 2.024 - 8.732

Nitrate (umol/L): 13.189 - 31.290

Salinity (PPS): 34.055 - 35.501

Oxygen (ml/l): 4.022 - 6.389

Phosphate (umol/l): 0.923 - 2.511

Silicate (umol/l): 7.726 - 48.790
 
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.

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Habitat Type: Marine

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Depth: 0 - 1200m.
Recorded at 1200 meters.

Habitat: benthopelagic. Not found in Southern Africa - Pers Comm Len Compagn January 22 2003.
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Benthopelagic; brackish; marine. Depth range; 0-1200 m. Found on continental and insular shelves and upper slopes down to at least 1,200 m . In the Arctic and boreal Atlantic, it occurs inshore in the intertidal and at the surface in shallow bays and river mouths during colder months, and when the temperature rises, retreats to depths of 180-550 m.
  • Bigelow, H. B. and Schroeder, W. C., 1953; Compagno, L. J. V., 1984; Compagno, L. J. V., D. A. Ebert and M. J. Smale, 1989.
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Migration

Non-Migrant: No. All populations of this species make significant seasonal migrations.

Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).

Locally Migrant: No. No populations of this species make annual migrations of over 200 km.

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Trophic Strategy

Ommatokoita elongata (copepod) is a parasite of the species, attached to the cornea of its eye (Ref. 5951).
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Food Habits

Fish, marine mammals, and carrion are three staples in the diet of Somniosus pacificus. Fish include herring (Clupeinae), salmon (Salmonidae), smelt (Osmeridae), cod (Gadidae), pollock (Theragra), haddock (Melanogrammus), halibut (Hippoglossus), redfish (Hoplostethus), sculpins (Cottoidei), lumpfish (Cyclopterus), and skates (Rajiformes). Seals (Phocidae) and small whales (Delphinidae) are also common food items. Drowned horses and reindeer have also been found in the stomachs of captured specimens. Somniosus pacificus has been observed feeding in great numbers on carrion produced by commercial whaling and fishing operations.

Animal Foods: mammals; fish; carrion ; mollusks; aquatic crustaceans; echinoderms; cnidarians

Primary Diet: carnivore (Piscivore )

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Feeds on pelagic and bottom fish, sharks and skates, seals and small cetaceans, sea birds, squids, crabs, amphipods, marine snails, brittle stars, sea urchins, and jellyfish.
  • Bigelow, H. B. and Schroeder, W. C., 1953; Compagno, L. J. V., 1984; Compagno, L. J. V., D. A. Ebert and M. J. Smale, 1989.
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Associations

Ecosystem Roles

Many of these sharks have copepod parasites, Ommatokoita elongata, attached to the corneas of their eyes. A single, female copepod will attach itself to one of the corneas, resulting in corneal damage and blindness in one eye. This does not seem to negatively effect the shark, as they do not rely on their vision. It has been suggested that the bioluminescence of these parasites helps lure prey, thus resulting in a mutualistic relationship, but there is no evidence to support this.

Mutualist Species:

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Predation

There are no known predators of adult Greenland sharks because of their very large size.

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Known prey organisms

Somniosus microcephalus preys on:
benthonic invertebrates
Boreogadus saida
Vertebrata
Phoca groenlandica
Phoca
Phoca hispida
Monodon monoceros

Based on studies in:
Arctic (Marine)

This list may not be complete but is based on published studies.
  • M. J. Dunbar, Arctic and subarctic marine ecology: immediate problems, Arctic 7:213-228, from p. 223 (1954).
  • Myers, P., R. Espinosa, C. S. Parr, T. Jones, G. S. Hammond, and T. A. Dewey. 2006. The Animal Diversity Web (online). Accessed February 16, 2011 at http://animaldiversity.org. http://www.animaldiversity.org
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Life History and Behavior

Behavior

Diet

Feed on fishes, including herring, Atlantic salmon, Arctic char, capelin, redfish, sculpins, lumpfish, cod, haddock, Atlantic halibut, Greenland halibut and skates, as well as cephalopods, gastropods, crustaceans, sea birds and marine mammals.
  • North-West Atlantic Ocean species (NWARMS)
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Communication and Perception

Like all sharks, Somniosus pacificus has a lateral line which aids in the detection of movement in the surrounding waters. Sharks also have especially keen chemical perception. No communication has been observed within the species.

Perception Channels: tactile ; vibrations ; chemical ; electric

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Life Cycle

Ovoviviparous (Ref. 247). Distinct pairing with embrace (Ref. 205).
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Development

Development in Somniosus pacificus is ovoviviparous; litters of up to ten pups have been observed. Size of fully grown young at birth has not been confirmed but is thought to be around forty centimeters. Most adults grow to between two and four meters in length.

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Life Expectancy

Lifespan/Longevity

No specific information about the longevity of Somniosus pacificus exists. Some scientists speculate that these sharks may live in excess of 100 years.

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Reproduction

Mating by this species has never been observed, but females have been found with mating scars on their caudal fins. Therefore, it is inferred that, as is the case with most sharks, males bite females until they submit. Fertilization occurs internally.

Mating System: polygynandrous (promiscuous)

Mating has never been observed in this species and little information is available concerning reproduction in Greenland sharks or related species.

Average number of offspring: 10.

Key Reproductive Features: iteroparous ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization (Internal ); ovoviviparous

There is no specific information on parental investment in Greenland sharks. However, most sharks are independent immediately after birth. Females provide developing embryos with rich food sources to support their development.

Parental Investment: pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female)

  • Compagno, L. 1984. FAO Species Catalogue Volume 4:Sharks of the World. Rome: United Nations Development Programme.
  • Compagno, L., S. Fowler. 2005. Sharks of the World. Princeton, New Jersey: Princeton University Press.
  • 2005. "Greenland Shark and Elasmobranch Research and Education Group" (On-line). Accessed October 18, 2005 at http://www.geerg.ca.
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Ovoviviparous.
  • Bigelow, H. B. and Schroeder, W. C., 1953; Compagno, L. J. V., 1984; Compagno, L. J. V., D. A. Ebert and M. J. Smale, 1989.
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Molecular Biology and Genetics

Molecular Biology

Statistics of barcoding coverage: Somniosus microcephalus

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 6
Specimens with Barcodes: 28
Species With Barcodes: 1
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Conservation

Conservation Status

IUCN Red List Assessment


Red List Category
NT
Near Threatened

Red List Criteria

Version
3.1

Year Assessed
2006

Assessor/s
Kyne, P.M., Sherrill-Mix, S.A. & Burgess, G.H.

Reviewer/s
Heupel, M.R., Simpfendorfer, C.A. & Cavanagh, R.D. (Shark Red List Authority)

Contributor/s

Justification
A large dogfish of the Arctic and North Atlantic, inhabiting inshore zones to continental shelves and slopes usually in depths of 0 to 1,200 m (one individual recorded at 2,200 m). Maximum size is uncertain but reaches at least 640 cm total length (TL), possibly to 730 cm TL, with most adults between 244 to 427 cm TL. This appears to be an extremely long-lived and slow-growing elasmobranch with limited reproductive capacity. Historically targeted for its liver oil in Norway, Iceland and Greenland with catches reaching 32,000 sharks/year in the 1910s in Greenland alone. These fisheries may have had a significant impact on this species, but the rate of historical decline (if any) is unknown. Presently taken as bycatch in trawl, gillnet and trap fisheries, as well as in Arctic artisanal fisheries. Its population dynamics and biology are not well understood but its large size and slow growth rate suggest it is vulnerable to fishing pressure. This shark is listed as Near Threatened on the basis of possible population declines and limiting life history characteristics. There is a need to examine historical data and monitor current bycatch levels.
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The status of Greenland shark populations are not well known. They support a fishery for liver oil in Greenland, Norway, and Iceland, but some researcher suspect that populations have diminished. They have an estimated population doubling time of 14 years.

US Federal List: no special status

CITES: no special status

IUCN Red List of Threatened Species: near threatened

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National NatureServe Conservation Status

Canada

Rounded National Status Rank: NNR - Unranked

United States

Rounded National Status Rank: NNR - Unranked

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NatureServe Conservation Status

Rounded Global Status Rank: GNR - Not Yet Ranked

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Population

Population
Unknown.

Population Trend
Unknown
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Threats

Major Threats
The Greenland shark was historically targeted by shark liver fisheries in Norway, Iceland, and Greenland waters. These fisheries may have had a significant impact on this species. The Greenland fishery commenced in the very early nineteenth century. In 1857 the estimated catch was 2,000?3,000 sharks/year, but in the 1910s this had grown to 32,000 sharks/year (Jensen 1914). Commercial fishing of the Greenland shark for liver oil ceased in 1960 (Castro et al. 1999). During the 1970s the species was perceived as a problem for other fisheries in western Norway and the government subsidized a fishery in order to reduce the stock of the species (Catro et al. 1999).

Currently the species is taken as bycatch in Greenland halibut and shrimp trawl fisheries (D. Kulka, pers. comm.) and fish traps and gillnets. It is also caught by artisanal fisheries in the Arctic (Compagno in prep. a).
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Near Threatened (NT)
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Management

Conservation Actions

Conservation Actions
There is a need to research the historical catch data if available, to determine any population declines as a result of the fisheries. Bycatch rates in various fisheries around the Artic and north Atlantic need to be determined and monitored.
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Relevance to Humans and Ecosystems

Benefits

Importance

fisheries: minor commercial; gamefish: yes; price category: low; price reliability: reliable: based on ex-vessel price for this species
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Economic Importance for Humans: Negative

Unless properly washed or dried, Greenland shark meat is toxic to humans. Like most sharks, Greenland sharks rarely attack unless harassed.

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Economic Importance for Humans: Positive

Somniosus pacificus is commonly fished by people in the Arctic regions (Norway, Iceland, and Greenland) for its liver oil and meat. People of the Inuit tribes have also been known to use its skin to make boots and its teeth as knives.

Positive Impacts: food ; body parts are source of valuable material

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Wikipedia

Greenland shark

The Greenland shark (Somniosus microcephalus), also known as the gurry shark or grey shark, or by the Inuit name Eqalussuaq, is a large shark of the family Somniosidae ("sleeper sharks") that is native to the waters of the North Atlantic Ocean around Canada, Greenland, and Iceland. These sharks live farther north than any other shark species. Many of the species' adaptations are due to it being the only truly sub-Arctic species of shark. They are closely related to the Pacific sleeper shark.[2] This species of the shark holds the world record for being the most poisonous in its type.[3]

Description[edit]

This is one of the largest living species of shark, of dimensions comparable to those of the great white shark. Greenland sharks grow to 6.4 m (21 ft) and 1,000 kg (2,200 lb),[4] and possibly up to 7.3 m (24 ft) and more than 1,400 kg (3,100 lb).[5][6] However, most Greenland sharks observed have been around 2.44–4.8 m (8.0–15.7 ft) long and weigh up to 400 kg (880 lb).[5][6] Males are typically smaller than females. It rivals the Pacific sleeper shark (possibly up to 7 m or 23 ft long) as the largest species in the family Somniosidae. The Greenland Shark is a thickset species with a short, rounded snout, small eyes, and very small dorsal and pectoral fins. The gill openings are very small for the species' great size. Coloration can range from pale creamy-gray to blackish-brown and the body is typically uniform in color, though whitish spots or faint dark streaks are occasionally seen on the back.[5] Due to their cold environments, Greenland Sharks are thought to grow at a very slow rate.[5] There are no reliable data on their life span, but fully grown Greenland sharks have been recaptured 16 years after being tagged.[7]

Dentition[edit]

The dentition of a Greenland shark.

When feeding on large carcasses, the shark employs a rolling motion of its jaw. The teeth of the upper jaw are very thin and pointed, lacking serrations. These upper jaw teeth, numbering from 48 to 52 teeth, act as anchor while the lower jaw does the cutting. The lower teeth are interlocking and are broad and square, 50 to 52 in count, containing short, smooth cusps that point outward.[5] Teeth in the two halves of the lower jaw are strongly pitched in opposite directions.[8]

Life history[edit]

The Greenland shark is an apex predator mostly eating fish. Recorded fish prey have included smaller sharks, skates, eels, herring, capelin, Arctic char, cod, redfish, sculpins, lumpfish, wolffish and flounders.[5] However, it may also prey on marine mammals such as seals. Bite marks on dead seals at Sable Island, Nova Scotia and Hawarden suggest that this shark may be a major predator for them in the winter months.[9] Rarely, these sharks have been found as far south as the Gulf of Mexico.[10]

Since Greenland sharks are perhaps one of the slowest-swimming shark and attain a maximum swimming speed that is about half the maximum swimming speed of a typical seal, biologists have wondered how the sharks are able to predate the seals. Some evidence has been found that Greenland sharks search out seals and ambush them while they sleep.[11] Greenland sharks have also been found with remains of polar bear, horses, moose[12] and reindeer (in one case an entire reindeer body) in their stomachs.[5][13] The Greenland shark is also known to be a scavenger but to what extent carrion (almost certainly the origin of the reindeer) figures into the slow-moving fish's stomach contents is unknown. It is known, however, that the species is attracted by the smell of rotting meat in the water. They often congregate in large numbers around fishing operations.[5] The shark is colonized by the parasitic copepod Ommatokoita elongata that eats the shark's corneal tissue. It has been reported that this parasite is bioluminescent and gives the shark a greenish glow around the eye when seen in dark waters but this has not been scientifically supported.[5][14] The shark occupies what tends to be a very deep environment seeking its preferable cold water (−0.6 to 10 °C (30.9 to 50.0 °F)) habitat. It has been observed at a depth of 2,200 m (7,200 ft) by a submersible investigating the wreck of the SS Central America. A specimen video-taped at 2,773 m (9,098 ft) off the coast of Brazil on 11 February 2012 may have been a Greenland shark, but cannot be distinguished in the video from a southern sleeper shark or Pacific sleeper shark.[15] However, a more typical depth for the species is above 1,200 m (3,900 ft). Frequently during the winter, when the sharks look for warmer waters to inhabit, they are often found at or near the surface of the water.[5]

As an ectotherm, the Greenland shark is slow, cruising at 0.76 mph with a top speed of 1.6 mph.[16]

Greenland sharks are thought to be the longest-lived vertebrates on the planet, with a potential life span of over 200 years.[17][18][19]

Reproduction[edit]

As recently as 1957 it was found that the females do not deposit eggs in the bottom ooze, but retain the developing embryos within their bodies so that they are born alive after an undetermined gestation period. 10 pups per litter is normal, each initially measuring some 90 cm (35 in) in length.[20]

Greenland sharks as food[edit]

The flesh of a Greenland shark is poisonous. This is due to the presence of the toxin trimethylamine oxide, which, upon digestion, breaks down into trimethylamine, producing effects similar to extreme drunkenness. Occasionally, sled dogs that end up eating the flesh are unable to stand up due to the neurotoxins. Similar toxic effects occur with the related Pacific sleeper shark, but not in most other shark species, whose meat is often consumed fresh.[21]

However, it can be eaten if it is boiled in several changes of water or dried or fermented for some months to produce Kæstur Hákarl, often Hákarl for short. Traditionally this was done by burying the shark in boreal ground, exposing it to several cycles of freezing and thawing. It is considered a delicacy in Iceland and Greenland.

Inuit legends[edit]

The shark is not considered dangerous to humans, though there are Inuit legends of this species attacking kayaks.[22] Although it is likely the very large shark could easily consume a human swimmer, the extremely cold waters it typically inhabits makes the likelihood of attacks on humans very low, and there are no verified cases of predation on people.[5]

The Greenland shark's poisonous flesh has a high urea content, which gave rise to the Inuit legend of Skalugsuak, the first Greenland shark.[23] The legend says that an old woman washed her hair in urine and dried it with a cloth. The cloth blew into the ocean to become Skalugsuak.[24]

The Greenland shark plays a role in cosmologies of the Inuit from the Canadian Eastern Arctic and Greenland. Igloolik Inuit believe that the shark lives within Sedna's urine pot, and consequently its flesh has an urine-like smell, and acts as a helping spirit to shamans.[25]

Research[edit]

The Greenland Shark and Elasmobranch Education and Research Group (GEERG) has been studying the Greenland shark in the Saguenay Fjord and St. Lawrence Estuary since 2001. The Greenland shark has repeatedly been documented (captured or washed ashore) in the Saguenay since at least 1888.[24] Accidental captures and strandings have also been recorded in the St. Lawrence Estuary for over a century.

Current research conducted by GEERG involves the study of the behaviour of the Greenland shark by observing it underwater using scuba and video equipment and by placing acoustic and satellite tags (telemetry) on live specimens; however, overall very little is known about this mysterious species.

There is now an argument suggesting that the Greenland shark is responsible for 'Seal Ripping' attacks on grey seals.[26] These attacks cause a corkscrew pattern of cuts and tears which spiral around a seal's body, following the grain of the collagen within the muscles and running at 45 degrees to the seal's body. Seal deaths have been occurring over larger territories, including the north and east coasts of the UK, which suggests that the Greenland shark may be moving beyond its traditional habitat range. In August 2013, researchers from Florida State University caught the first documented Greenland shark in the Gulf of Mexico.[27] However, recent research into the UK "corkscrew" seal deaths by the Sea Mammal Research Unit [28] concluded that the UK seal deaths were unlikely to have been caused by predation from the Greenland shark, rather being caused by blunt mechanical trauma "consistent with the seals being drawn through a ducted propeller" that are found on many ships. Additionally, the shark's slow speed (max speed of 1.6 mph) limits its potential predation of seals to those that are asleep.[16]

See also[edit]

References[edit]

  1. ^ Kyne, P. M., Sherrill-Mix, S. A. & Burgess, G. H. (2006). "Somniosus microcephalus". IUCN Red List of Threatened Species. Version 2011.2. International Union for Conservation of Nature. Retrieved 5 February 2012. 
  2. ^ O'Donnell, Jacinth. Jurassic Shark documentary (2000); broadcast on Discovery Channel, 5 August 2006
  3. ^ Guinness World Records 2013, Page 048, Hardcover edition.
  4. ^ Mills, Patrick (2006). "Somniosus microcephalus". In Dewey, Tanya. Animal Diversity Web. University of Michigan. 
  5. ^ a b c d e f g h i j k Eagle, Dane. "Greenland shark". Florida Museum of Natural History. Retrieved 26 June 2012. 
  6. ^ a b Wood, Gerald (1983). The Guinness Book of Animal Facts and Feats. ISBN 978-0-85112-235-9. [page needed]
  7. ^ Caloyianis, Nick (September 1998). "Greenland Sharks". National Geographic 194 (3): 60–71. 
  8. ^ "Greenland Shark". Marinebiodiversity.ca. Retrieved 23 May 2011. 
  9. ^ Lucas, Zoe (March 2003). "Shark Predation on Sable Island Seals". Sable Island Green Horse Society. Retrieved 26 June 2012. [self-published source?]
  10. ^ "What Is a Greenland Shark Doing in the Gulf of Mexico?". Wired. 2013-08-27 
  11. ^ Scales, Helen (June 2012). "Slow Sharks Sneak Up on Sleeping Seals (and Eat Them)?". National Geographic News. Retrieved 28 December 2012. 
  12. ^ "Moose-eating shark rescued in Newfoundland harbour". CBC News. 21 November 2013. Retrieved 21 November 2013. 
  13. ^ Howden, Daniel (12 August 2008). "Clash of the fiercest predators as shark eats polar bear". The Independent. Retrieved 26 June 2012. 
  14. ^ "Greenland Shark". Discovery. Retrieved 23 May 2011. [unreliable source?]
  15. ^ "Video: Greenland shark at over 9100 feet deep (2770 m) off Brazil". The Dorsal Fin. Retrieved 21 February 2012. [unreliable source?]
  16. ^ a b Watanabe, Yuuki Y.; Lydersen, Christian; Fisk, Aaron T.; Kovacs, Kit M. (2012). "The slowest fish: Swim speed and tail-beat frequency of Greenland sharks". Journal of Experimental Marine Biology and Ecology. 426–427: 5. doi:10.1016/j.jembe.2012.04.021. 
  17. ^ GEERG – Greenland Shark. Geerg.ca. Retrieved on 22 November 2013.
  18. ^ The Greenland shark – world’s oldest? Dutch Shark Society. 7 November 2013.
  19. ^ GEERG – Greenland Shark. Geerg.ca. Retrieved on 12 July 2013.
  20. ^ "Polar Seas: Greenland Shark". Elasmo-research.org. Retrieved 23 May 2011. 
  21. ^ Waldner, Ray (21 December 2004). "Shark Eating". Sport Fishing Magazine. Retrieved 26 June 2012. 
  22. ^ Stinson, Scott (24 October 2003). "Skipper Uses Knife To Kill 600-Kilo Shark". National Post. Archived from the original on 2 November 2003. 
  23. ^ O’Reilly, Lindsay. "The Greenland Shark", Canadian Geographic, March/April 2004. Retrieved 1 July 2007.
  24. ^ a b "Greenland Shark and Elasmobranch Education and Research Group". Geerg.ca. Retrieved 23 May 2011. 
  25. ^ Idrobo, Carlos Julián (2008) The Pangnirtung Inuit and the Greenland Shark. p. 66. MSc Thesis. Faculty of Environment, Earth and Resources, University of Manitoba
  26. ^ Channel 5 documentary Retrieved 29 September 2010
  27. ^ Grubs, Dean (15 August 2013). "Deep-C Scientists Capture First Greenland Shark in the Gulf of Mexico"
  28. ^ "Sea Mammal Research Unit" "Report on recent seal mortalities in UK waters caused by extensive lacerations", October 2010. Retrieved 5 January 2011

Further reading[edit]

  • MacNeil, M. A.; McMeans, B. C.; Hussey, N. E.; Vecsei, P.; Svavarsson, J.; Kovacs, K. M.; Lydersen, C.; Treble, M. A. et al. (2012). "Biology of the Greenland shark Somniosus microcephalus". Journal of Fish Biology 80 (5): 991–1018. doi:10.1111/j.1095-8649.2012.03257.x. PMID 22497371. 
  • Watanabe, Yuuki Y.; Lydersen, Christian; Fisk, Aaron T.; Kovacs, Kit M. (2012). "The slowest fish: Swim speed and tail-beat frequency of Greenland sharks". Journal of Experimental Marine Biology and Ecology. 426–427: 5–11. doi:10.1016/j.jembe.2012.04.021. Lay summaryLiveScience (25 June 2012). 
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