The hooded seal (Cystophora cristata) is a large phocid found only in the central and western North Atlantic, ranging from Svalbard in the east to the Gulf of St. Lawrence in the west. The seals are typically silver-grey or white in colour, with black spots that vary in size covering most of the body. Hooded seal pups are known as "blue-backs" because their coats are blue-grey on the back with whitish bellies, though this coat is shed after 14 months of age when the pups molt.
|Specimen at Museum Koenig|
|Distribution of the hooded seal. Breeding grounds indicated in blue.|
a peculiar inflatable bladder septum on the head of the adult male. This bladder hangs between the eyes and down over the upper lip in the deflated state. In addition, the hooded seal can inflate a large balloon-like sac from one of its nostrils. This is done by shutting one nostril valve and inflating a membrane, which then protrudes from the other nostril.
Adult males are 2.6 metres (8 ft 6 in) long on average, and weigh 300–410 kg (660–900 lb). Sexual dimorphism is obvious from birth and females are much smaller: 2.03 metres (6 ft 8 in) long and weighing 145–300 kg (320–661 lb). The colour is silvery; the body is scattered with dark, irregular marks. The head is darker than the rest of the body, and without marks.
Hooded seals live primarily on drifting pack ice and in deep water in the Arctic Ocean and North Atlantic. Although some drift away to warmer regions during the year, their best survival rate is in colder climates. They can be found on four distinct areas with pack ice: near Jan Mayen Island (northeast of Iceland); off Labrador and northeastern Newfoundland; the Gulf of St. Lawrence; and the Davis Strait (off midwestern Greenland). Males appear to be localized around areas of complex seabed, such as Baffin Bay, Davis Strait, and the Flemish cap, while females concentrate their habitat efforts primarily on shelf areas, such as the Labrador Shelf. Hooded seals are known to be a highly migratory species that often wander long distances, as far west as Alaska and as far south as the Canary Islands and Guadeloupe. Prior to the mid 1990s, hooded seal sightings in Maine and the east Atlantic were rare, but began increasing in the mid 1990s. From January 1997 to December 1999, a total of 84 recorded sightings of hooded seals occurred in the Gulf of Maine, one in France and one in Portugal. From 1996 to 2006, five strandings and sightings were noted near the Spanish coasts in the Mediterranean Sea. There is no scientific explanation for the increase in sightings and range of the hooded seal.
The diet of the hooded seal is composed primarily of various amphipods (crustaceans), eeuphausiids (krill), and fish, including Atlantic Argentine, capelin, Greenland halibut, cod, herring, and redfish. They also are known to eat squid, sea stars, and mussels. Relative to the other species, hooded seals consume 3 times the proportion of redfish; percentages of capelin were similar in relation to closely related species. Capelin is considered a more common choice of sustenance during the winter season. Their diet is considered to be rich in lipids and fatty acids.
Hooded seals tend to feed in relatively deep waters ranging from 100–600 m (330–1,970 ft), and dive from 5 to 25 minute durations. However, some dives can go deeper than 1,016 m (3,333 ft) and as long, or longer, than 52 minutes. Diving is rather continuous, with approximately 90% of their time spent submerged during the day and night, although dives during the day are generally deeper and longer. Dives during the winter are also deeper and longer than those in the summer. It is known that the hooded seal is generally a solitary species, except during breeding and moulting seasons. During these two periods, they tend to fast as well. The seals mass annually near the Denmark strait around July, at the time of their moulting periods, to mate. Hooded seals are a relatively unsocial species compared to other seals, and they are typically more aggressive and territorial. They demonstrate aggression by inflating the "hood" (which is explained in the "Nasal Cavity" section below). They frequently migrate and remain alone for most of the year, except during mating season.
The hooded seal is known for its uniquely elastic nasal cavity located at the top of its head, also known as the hood. Only males possess this display-worthy nasal sac, which they begin to develop around the age of four. The hood begins to inflate as the seal makes its initial breath prior to going underwater. It then begins to repetitively deflate and inflate as the seal is swimming. The purpose of this happening is for acoustic signaling, meaning that it occurs when the seal feels threatened and attempts to ward off hostile species when competing for resources such as food and shelter. It also serves to communicate their health and superior status to both other males and females they are attempting to attract. In sexually mature males, a pinkish balloon-like nasal membrane comes out of the left nostril to further aid it in attracting a mate. This membrane, when shaken, is able to produce various sounds and calls depending on whether the seal is underwater or on land. Most of these acoustic signals are used in acoustic situation (about 79%), while about 12% of the signals are used for sexual purposes.
There are four major breeding areas for the hooded seal: the Gulf of St. Lawrence; the "Front" east of Newfoundland; Davis Strait (between Greenland and northern Canada); and the West Ice near Jan Mayen. Male hooded seals are known to have several mates in a single mating season, following the hypothesis that they are polygynous. While some males will defend and mate with just one female for long periods of time, others will be more mobile and tend to mate with multiple females for shorter periods of time, generating maximum offspring within the population. Most males reach sexual maturity by 5 years of age.
Throughout all areas, the hooded seals whelp in late March and early April and molt from June to August. The four recognized herds are generally sorted into two distinct populations: a Northeast (NE) Atlantic population and a Northwest (NW) Atlantic population. It is estimated that 90% of the total NW population give birth on the "Front". The NE herd whelping (giving birth) around Jan Mayen generally disperse into the sea after they breed in March. From April through June, after the breeding season, this species travels long distances to feed and then eventually gather together once again. Although some individuals return to the same area of ice in July to undergo moulting, the majority of the herd moult further North. After moulting, the species disperses widely again to feed in the late summer and autumn before returning to the breeding areas again in late winter.
Pups are about 1 metre (3 ft 3 in) long at birth and weigh about 24 kilograms (53 lb). They are born on the ice from mid-March to early April with a well-developed blubber layer and having shed their pre-natal coat. They are born with a slate blue-grey coat (giving them the name "blueback"), with a pale cream colour on the belly, which they will moult after about 14 months. Nursing of the pup lasts for an average of only 4 days, the shortest lactation period of any mammal, during which the pup doubles in size, gaining around 7 kg/day. This is possible because the milk that they drink has a fat content of 60%. The female pup will mature between ages 3 and 6, whereas the male pup will mature between ages 5 and 7.
Researchers find that due to a pup's differing needs in regards to sustaining work and foraging while under water compared to adults, the skeletal and cardiac muscles develop differently. Studies show that cardiac blood flow provides sufficient O2 to sustain lipolytic pathways during dives, remedying their hypoxic challenge. Cardiac tissue is found to be more developed than skeletal muscles at birth and during the weaning period, although neither tissue is fully developed by the end of the weaning period. Pups are born with fully developed hemoglobin stores (found in blood), but their myoglobin levels (found in skeletal tissue) are only 25–30% of adult levels. These observations conclude that pup muscles are less able to sustain both aerobic ATP and anaerobic ATP production during dives than adults are. This is due to the large stores of oxygen, either bound to hemoglobin or myoglobin, which the seals rely on to dive for extended periods of time. This could be a potential explanation for pups’ short weaning period as diving is essential to their living and survival.
The hooded seal can live to about age 30 to 35.
Prior to the 1940s, adult hooded seals were primarily hunted for their leather and oil deposits. More recently, the main threats are hunting, including subsistence hunting, and bycatch. Seal strandings are not considered a large threat to Hooded Seal populations but are highly researched. Seal pups are hunted for their blue and black pelts and many mothers are killed in the process, attempting to protect their young. Hunting primarily occurs in areas of Greenland, Canada, Russia, and Norway. Overall, northwest Atlantic Hooded Seal populations are stable or increasing whereas the northeast Atlantic populations have declined by 85–90% within the last 60 years.
It was believed by the scientific community that sonar was leading to mass stranding of Hooded Seals. After multiple sonar tests on captive seals, ranging from 1 to 7 kHz, it became evident that it had little effect on the subjects. The first test on each subject yielded differing results, ranging from reduced diving activity and rapid exploratory swimming. A difference was only noted for all subjects on their initial exposure.
Conservation practices, brought about by international cooperation and the formation of the Northwest Atlantic Fisheries Organization (NAFO) led to Hooded Seal population increases. It is now required to hold a license to hunt Hooded Seals in international waters and each license is set a quota. Total allowable catch of hooded seals are set at 10,000 annually.
Blueback may refer to any of a number of unrelated fish species with blue coloration:
Blueback (novel), a 1997 novel by Australian author Tim Winton
USS Blueback (SS-326), a US Navy submarine of the Balao-class
USS Blueback (SS-581), a Barbel-class submarine and the last non-nuclear submarine to join the US Naval Fleet
Beardslee trout or bluebacks
Blueback, a juvenile hooded sealBrucella pinnipedialis
Brucella pinnipedialis is a species of bacteria. It causes infections and related diseases primarily in pinnipeds and cetaceans.Diphyllobothrium elegans
Diphyllobothrium elegans is a species of tapeworms. It has been found in the hooded seal (Cystophora cristata).Earless seal
The earless seals, phocids or true seals are one of the three main groups of mammals within the seal lineage, Pinnipedia. All true seals are members of the family Phocidae . They are sometimes called crawling seals to distinguish them from the fur seals and sea lions of the family Otariidae. Seals live in the oceans of both hemispheres and, with the exception of the more tropical monk seals, are mostly confined to polar, subpolar, and temperate climates. The Baikal seal is the only species of exclusively freshwater seal.Greenland Sea
The Greenland Sea is a body of water that borders Greenland to the west, the Svalbard archipelago to the east, Fram Strait and the Arctic Ocean to the north, and the Norwegian Sea and Iceland to the south. The Greenland Sea is often defined as part of the Arctic Ocean, sometimes as part of the Atlantic Ocean. However, definitions of the Arctic Ocean and its seas tend to be imprecise or arbitrary. In general usage the term "Arctic Ocean" would exclude the Greenland Sea. In oceanographic studies the Greenland Sea is considered part of the Nordic Seas, along with the Norwegian Sea. The Nordic Seas are the main connection between the Arctic and Atlantic oceans and, as such, could be of great significance in a possible shutdown of thermohaline circulation. In oceanography the Arctic Ocean and Nordic Seas are often referred to collectively as the "Arctic Mediterranean Sea", a marginal sea of the Atlantic.The sea has Arctic climate with regular northern winds and temperatures rarely rising above 0 °C (32 °F). It previously contained the Odden ice tongue (or Odden) area, which extended eastward from the main East Greenland ice edge in the vicinity of 72–74°N during the winter and acted as a key winter ice formation area in the Arctic. The West Ice forms in winter in the Greenland Sea, north of Iceland, between Greenland and Jan Mayen island. It is a major breeding ground of harp seal and hooded seal that has been used for seal hunting for more than 200 years.Grenen
Grenen is a long sandbar spit at Skagen Odde (the headland of Jutland), north of the town of Skagen.Ice seal
Ice seal, or (in the Southern Hemisphere) pack-ice seal is a general term applied to any one of a number of pinniped species of the family Phocidae whose life cycle is completed largely on or about the sea ice of the Earth's polar regions.
The following are widely considered pagophilic or "ice-loving" species:
Weddell sealSubfamily Phocinae
Spotted seal or larga sealKangaatsiaq
Kangaatsiaq (old spelling: Kangâtsiaq) is a town located at the northern end of the Qeqertalik municipality in western Greenland. The town received town status as recently as 1986, though as a settlement it has existed much longer. It has 558 inhabitants as of 2013. Nearby settlements are Attu, Niaqornaarsuk, Ikerasaarsuk and Iginniarfik.List of Arctic pinnipeds
This is a list of Arctic pinnipeds:
Phocidae (ᓇᑦᓯᖅ, natsiq)Bearded seal (ᐅᒡᔪᒃ, ᐅᒥᒃᑑᖅ, ugjuk) Erignathus barbatus
Hooded seal (ᓇᑦᓯᕙᒃ, natsivak) Cystophora cristata
Harbor seal (ᖃᓯᒋᐊᖅ, qasigiaq) Phoca vitulina
Harp seal (ᖃᐃᕈᓕᒃ, qairulik) Pagophilus groenlandicus
Grey seal (ᐳᕕᓲᖅ, puvisuuq) Halichoerus grypus
Ringed seal (ᓇᑦᑎᖅ, nattiq) Pusa hispida
Northern elephant seal Mirounga angustirostris
Ribbon seal (Histriophoca fasciata)
Spotted seal (Phoca largha, Phoca vitulina largha)
Northern fur seal (Callorhinus ursinus)
OdobenidaeWalrus (ᐊᐃᕕᖅ, aiviq) Odobenus rosmarusList of mammals of Norway
List of mammals with non-domesticated populations in Norway.List of mammals of South Carolina
This is a list of mammals that are or were in the past native to South Carolina.
BalaenopteridaeBowhead whale (Balaena mysticetus)
Fin whale (Balaenoptera physalus)
Humpback whale (Megaptera novaengliae)
Minke whale (Balaenoptera acutorostrata)
Right whale (Eubalaena glacialis)
Sei whale (Balaenoptera borealis)BovidaeBison (Bison bison)CanidaeCoyote (Canis latrans)
Grey fox (Urocyon cinereoargenteus)
Red fox (Vulpes vulpes)
Gray wolf (Canis lupus)
Red wolf (Canis rufus)CervidaeElk (Cervus elaphus)
White-tailed deer (Odocoileus virginianus)DasypodidaeNine-banded armadillo (Dasypus novemcinctus)DelphinidaeAntillean beaked whale (Mesoplodon europaeus)
Atlantic pilot whale (Globicephala melaena)
Atlantic spotted dolphin (Stenella frontails)
Common bottlenose dolphin (Tursiops truncatus)
Dense-beaked whale (Mesoplodon densirostris)
False killer whale (Pseudorca crassidens)
Grampus (Grampus griseus)
Pantropical spotted dolphin (Stenella attenuata)
Rough-toothed dolphin (Steno bredanenis)
Saddleback dolphin (Delphinus delphis)
Short-finned pilot whale (Globicephala macrohyncha)
Spinner dolphin (Stenella longirostris)
Striped dolphin (Stenella coeruleoalba)
True's beaked whale (Mesoplodon mirus)DidelphimorphiaVirginia opossum (Didelphis virginiana)EquidaeHorse (Equus caballus)EschrichtiidaeGray whale (Eschrichtius robustus)FelidaeBobcat (Lynx rufus)
Mountain lion (Puma concolor)LeporidaeEastern cottontail (Sylvilagus floridanus)
Marsh rabbit (Sylvilagus palustris)
New England cottontail (Sylvilagus transitionalis)
Swamp rabbit (Sylvilagus aquaticus)MephitidaeSpotted skunk (Spilogal putorius)
Striped skunk (Mephitis mephitis)MolossidaeBrazilian free-tailed bat (Tadarida brasiliensis)MuridaeBlack rat (Rattus rattus)
Cotton mouse (Peromyscus gossypinus)
Deer mouse (Peromyscuc maniculatus)
Eastern harvest mouse (Reithrodontomys humulis)
Eastern woodrat (Neotoma Floridana)
Golden mouse (Ochrotomys nuttalli)
Hispid cotton rat (Sigmodon hispidus)
House mouse (Mus musculus)
Meadow vole (Microtus pennsylvanicus)
Muskrat (Ondatra zibethiscus)
Norway rat (Rattus norvegicus)
Oldfield mouse (Peromyscus polionotus)
Pine vole (Microtus pinetorum)
Red-backed vole (Clethrionomys gapperi)
Rice rat (Oryzomys palustris)
White-footed mouse (Peromyscus leucopus)MustelidaeLeast weasel (Mustela nivalis)
Long-tailed weasel (Mustela frenata)
Mink (Mustela vison)
North American river otter (Lutra canadensis)PhocidaeHarbor seal (Phoca vitulina)
Hooded seal (Cystophora cristata)PhocoenidaeHarbor porpoise (Phocoena phocoena)PhyseteridaeDwarf sperm whale (Kogia simus)
Pygmy sperm whale (Kogia breviceps)
Sperm whale (Physeter catodon)ProcyonidaeRaccoon (Procyon lotor)SciuridaeEastern chipmunk (Tamias striatus)
Grey squirrel (Sciurus carolinensis)
Least shrew (Cryptotis parva)
Masked shrew (Sorex cinereus)
Southern short-tailed shrew (Blarina carolinensis)SoricidaeAmerican pygmy shrew (Microsorex hoyi)
Red squirrel (Tamiasciurus hudsonicus)
Short-tailed shrew (Blarina brevicauda)
Smoky shrew (Sorex fumeus)
Southeastern shrew (Sorex longirostris)
Southern flying squirrel (Glaucomys volans)
Woodchuck (Marmota monax)SuidaeWild boar (Sus scrofa)TalpidaeEastern mole (Scalopus aquaticus)
Hairy-tailed mole (Parascalops breweri)
Star-nosed mole (Condylura cristata)TrichechidaeManatee (Trichechus manatus)UrsidaeBlack bear (Ursus americanus)VespertilionidaeBig brown bat (Eptesicus fuscus)
Eastern pipistrelle (Pipistrellus subflavus)
Eastern red bat (Lasiurus borealis)
Eastern small-footed bat (Myotis leibii)
Evening bat (Nycticeius humeralis)
Hoary bat (Lasiurus cinereus)
Indiana bat (Myotis sodalis)
Little brown bat (Myotis lucifugus)
Northern long-eared bat (Myotis septentrionalis)
Northern yellow bat (Lasiurus intermedius)
Rafinesque's big-eared bat (Plecotus rafinesqueii)
Seminole bat (Lasiurus seminolus)
Silver-haired bat (Lasionycteris noctivagans)
Southeastern myotis (Myotis austroriparius)ZapodidaeMeadow jumping mouse (Zapus hudsonius)
Woodland jumping mouse (Napaeozapus insignis)ZiphiidaeGoosebeaked whale (Ziphius carvirostris)Lutrogale
Lutrogale is a genus of otters, with only one extant species—the smooth-coated otter.Niaqornat
Niaqornat (Kalaallisut: "head-shaped") (IATA: NIQ) is a settlement in the Qaasuitsup municipality in northwestern Greenland. The settlement is located on the northern coast of the Nuussuaq Peninsula, with a wide view over Uummannaq Fjord. It had 58 inhabitants in 2010.Port George, Nova Scotia
Port George is a seaside community in the Canadian province of Nova Scotia, located in Annapolis County. It is a former port situated on the Bay of Fundy, 11 km north of Middleton, Nova Scotia just across North Mountain (Nova Scotia). It sits on the 45th parallel north.At one time Port George had a shipyard and carried on a good volume of sea trade in timber and agricultural produce with Boston and Saint John, New Brunswick. It was also a fishing port.The original name given to the area by the native Mi'Kmaq was "Goolwagopskooch" meaning "Haunt of the Hooded Seal". Originally settled in 1760, it is thought to have been re-settled in 1812 and named for King George III.Recognizable landmarks on its shorefront are the historic pepperpot lighthouse and the steeple of the old United Baptist church.
The community-owned pepperpot lighthouse, which dates to 1889, is an important navigational aid in the area. Originally it was situated on the end of one of two wharves, but when that wharf succumbed to storm damage it was moved in the early 1930s to its present position next to the road. It has a fixed red light, unique in the area, which is used for navigation by local sailors. The lighthouse was renovated in the summer of 2016 by the local community.
The Port George United Baptist church with its distinctive steeple was built in 1887. It is now a private residence.
Port George is a popular summer destination, with pretty cottages, a small seasonal art and gift shop and a 0.5ha provincial picnic park at Cottage Cove overlooking a seal colony on Dunn's Rock. Nearby is the community wharf with a new concrete boat ramp. One of few along this stretch of coastline.
Port George is well known for its annual country music jamboree which takes place on the last Saturday of July every year. The 34th annual jamboree in 2016 had an attendance of 2,750. A weekend of bluegrass jamming and old-time music is held every May holiday weekend at the recreation centre with a variety show on Saturday evening.Ringed seal
The ringed seal (Pusa hispida or Phoca hispida), also known as the jar seal, as netsik or nattiq by the Inuit and as Ньиэрпэ by the Yakut, is an earless seal (family: Phocidae) inhabiting the Arctic and sub-Arctic regions. The ringed seal is a relatively small seal, rarely greater than 1.5 m in length, with a distinctive patterning of dark spots surrounded by light grey rings, hence its common name. It is the most abundant and wide-ranging ice seal in the Northern Hemisphere: ranging throughout the Arctic Ocean, into the Bering Sea and Okhotsk Sea as far south as the northern coast of Japan in the Pacific, and throughout the North Atlantic coasts of Greenland and Scandinavia as far south as Newfoundland, and include two freshwater subspecies in northern Europe. Ringed seals are one of the primary prey of polar bears and killer whales, and have long been a component of the diet of indigenous people of the Arctic.Sea monk
The sea monk (also monk-fish or monkfish) was a sea creature found off the eastern coast of the Danish island of Zealand in 1546. It was described as a "fish" that looked superficially like a monk. The most recent study concluded that the animal was most likely an angelshark.Seal meat
Seal meat is the flesh, including the blubber and organs, of seals used as food for humans or other animals. It is prepared in numerous ways, often being hung and dried before consumption. Historically, it has been eaten in many parts of the world, both as a part of a normal diet, and as sustenance.
Practice of human consumption continues today in Japan, Norway, Iceland, Faroe Islands, the Inuit and other indigenous peoples of the United States (including the Makah people of the Pacific Northwest), Canada, Greenland; the Chukchi people of Siberia, and Bequia in the Caribbean Sea.West Ice
The West Ice is a patch of the Greenland Sea covered by pack ice during winter time. It is located north of Iceland, between Greenland and Jan Mayen island.
The West Ice is a major breeding ground for seals, especially harp seals and hooded seals. It was discovered in the early 18th century by British whalers. At the time, whalers were not interested in seal hunting as long as there was ample stock of bowhead whales in the area. However, after the 1750s, the whale population had been depleted in the area, and systematic seal hunting started, first by British ships and then by German, Dutch, Danish, Norwegian, and Russian ships. The annual catches were 120,000 animals around 1900, mostly by Norway and Russia, and rose to 350,000 by the 1920s. They then declined, first because of imposed restrictions on total allowable catch and then in response to decreasing market demand. Nevertheless, the seal population in the West Ice was rapidly falling, from an estimated 1,000,000 in 1956 to 100,000 in the 1980s. In the 1980s–1990s, takings of harp seals totaled 8,000–10,000, and annual catches of hooded seals totaled a few thousand between 1997 and 2001. Norway accounts for all recent seal hunting in the West Ice, as Russia has not hunted hooded seals since 1995, and catches harp seals at the East Ice in the White Sea – Barents Sea.Seal hunting in the West Ice was a dangerous occupation, as floating ice, storms and winds posed constant threat to the ships; in the 19th century, the hunters often encountered frozen human bodies on the West Ice. A major accident occurred around 5 April 1952 when a sudden storm surprised 53 ships hunting in the area. Seven of them sank and five vanished, namely Ringsel, Brattind and Vårglimt from Troms and Buskøy and Pels from Sunnmøre, with 79 men on board. The search for them involved ships and planes and continued for many days, but no trace of the missing boats was found.
Extant Carnivora species