Narwhal How Much Does a Baby Narwal Whigh

Medium-sized toothed whale that lives year-round in the Chill

Narwhal[ane] Temporal range: Quaternary-recent[2] [3]
Size compared to an average human
Conservation status
Least Concern (IUCN 3.1)[4]
CITES Appendix II (CITES)[5]
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Artiodactyla
Infraorder:	Cetacea
Family:	Monodontidae
Genus:	Monodon Linnaeus, 1758
Species:	M. monoceros
Binomial proper name
Monodon monoceros Linnaeus, 1758
The frequent (solid) and rare (striped) occurrence of narwhal populations

The narwhal, also known every bit a narwhale (Monodon monoceros), is a medium-sized toothed whale that possesses a large "tusk" from a protruding canine tooth. Information technology lives year-round in the Arctic waters around Greenland, Canada and Russian federation. It is one of two living species of whale in the family unit Monodontidae, along with the beluga whale. The narwhal males are distinguished by a long, straight, helical tusk, which is an elongated upper left canine. The narwhal was one of many species described past Carl Linnaeus in his publication Systema Naturae in 1758.

Like the beluga, narwhals are medium-sized whales. For both sexes, excluding the male's tusk, the total body size can range from three.95 to five.5 m (13 to xviii ft); the males are slightly larger than the females. The average weight of an developed narwhal is 800 to one,600 kg (ane,760 to 3,530 lb). At around 11 to xiii years old, the males go sexually mature; females become sexually mature at virtually 5 to viii years old. Narwhals do not have a dorsal fin and their neck vertebrae are jointed similar those of most other mammals, not fused as in dolphins and most whales.

Found primarily in Canadian Arctic and Greenlandic and Russian waters, the narwhal is a uniquely specialised Arctic predator. In winter, information technology feeds on benthic prey, mostly flatfish, under dense pack ice. During the summer, narwhals eat mostly Arctic cod and Greenland halibut, with other fish such every bit polar cod making up the residue of their diet.^[6] Each twelvemonth, they migrate from bays into the bounding main as summer comes. In the winter, the male narwhals occasionally dive up to 1,500 m (4,920 ft) in depth, with dives lasting up to 25 minutes. Narwhals, like virtually toothed whales, communicate with "clicks", "whistles" and "knocks".

Narwhals can live up to 50 years and are oft killed by suffocation after beingness trapped due to the germination of sea ice. Other causes of decease, specifically amidst young whales, are starvation and predation by orcas. Equally previous estimates of the world narwhal population were beneath 50,000, narwhals are categorised by the International Wedlock for Conservation of Nature (IUCN) as "nearly threatened". More recent estimates list higher populations (upwards of 170,000), thus lowering the condition to "least business organization".^[iv] Narwhals have been harvested for hundreds of years past Inuit people in northern Canada and Greenland for meat and ivory and a regulated subsistence hunt continues.

Taxonomy and etymology

Illustration of a narwhal (lower image) and a beluga (upper epitome), its closest related species

The narwhal was 1 of many species originally described by Carl Linnaeus in his landmark 1758 10th edition of Systema Naturae.^[7] Its name is derived from the Onetime Norse word nár, significant "corpse", in reference to the animal's greyish, mottled pigmentation, similar that of a drowned sailor^[eight] and its summertime habit of lying still at or near the surface of the sea (chosen "logging").^[9] The scientific name, Monodon monoceros, is derived from Greek: "one-tooth one-horn".^[8]

The narwhal is most closely related to the beluga whale. Together, these two species comprise the only extant members of the family unit Monodontidae, sometimes referred to equally the "white whales". The Monodontidae are distinguished past their medium size (at around 4 thou (thirteen.1 ft) in length), pronounced melons (round sensory organs), brusque snouts and the absence of a true dorsal fin.^[10]

Although the narwhal and the beluga are classified as separate genera, with one species each, there is some show that they may, very rarely, interbreed. The complete skull of an dissonant whale was discovered in West Greenland circa 1990. It was described by marine zoologists every bit unlike any known species, but with features midway betwixt a narwhal and a beluga, consistent with the hypothesis that the anomalous whale was a narwhal-beluga hybrid;^[11] in 2019, this was confirmed by DNA and isotopic analysis.^[12]

The white whales, dolphins (Delphinidae) and porpoises (Phocoenidae) together incorporate the superfamily Delphinoidea, which are of likely monophyletic origin. Genetic evidence suggests the porpoises are more closely related to the white whales and that these two families constitute a separate clade which diverged from the rest of Delphinoidea within the past xi meg years.^[13] Fossil testify shows that ancient white whales lived in tropical waters. They may have migrated to Arctic and sub-Arctic waters in response to changes in the marine food chain during the Pliocene.^[14]

Clarification

Narwhals are medium-sized whales and are around the aforementioned size as beluga whales. Total length in both sexes, excluding the tusk of the male, tin can range from iii.95 to five.5 m (13 to 18 ft).^[15] Males, at an boilerplate length of 4.1 thou (13.5 ft), are slightly larger than females, with an average length of iii.five grand (11.5 ft). Typical adult body weight ranges from 800 to 1,600 kg (one,760 to 3,530 lb).^[15] Male person narwhals attain sexual maturity at 11 to 13 years of historic period, when they are about 3.9 m (12.8 ft) long. Females go sexually mature at a younger historic period, between five and eight years old, when they are around 3.4 m (11.2 ft) long.^[15]

The pigmentation of narwhals is a mottled pattern, with blackish-brown markings over a white groundwork. They are darkest when born and go whiter with age; white patches develop on the bellybutton and genital slit at sexual maturity. One-time males may be nearly pure white.^{[8] [xv] [16]} Narwhals practice not have a dorsal fin, possibly an evolutionary adaptation to swimming hands under ice, to facilitate rolling, or to reduce area and heat loss. Instead narwhals possess a shallower dorsal ridge.^[17] Their neck vertebrae are jointed, similar those of country mammals, instead of being fused together every bit in most whales, assuasive a great range of cervix flexibility. Both these characteristics are shared by the fellow beluga whale.^[9] The tail flukes of female narwhals have front edges that are swept back and those of males have front edges that are more concave and lack a sweep-back. This is thought to be an adaptation for reducing drag caused by the tusk.^[eighteen]

Tusk

This narwhal skull has rare double tusks. Normally, the canine molar but on the left side of the upper jaw becomes a tusk. Rarely, males develop two tusks. This specimen, however, was of a female person (Zoologisches Museum, Hamburg; collected in 1684)

The near conspicuous characteristic of the male narwhal is a single long tusk, which is in fact a canine molar^{[xix] [20]} that projects from the left side of the upper jaw, through the lip and forms a left-handed helical spiral. The tusk grows throughout life, reaching a length of about 1.v to 3.one m (iv.9 to 10.2 ft). It is hollow and weighs effectually 10 kg (22 lb). Almost one in 500 males has ii tusks, occurring when the right canine also grows out through the lip. Only virtually 15 per centum of females grow a tusk,^[21] which typically is smaller than a male tusk, with a less noticeable spiral.^{[22] [23] [24]} Collected in 1684, there is but 1 known case of a female person growing a 2nd tusk (image).^[25]

Scientists have long speculated on the biological function of the tusk. Proposed functions include use of the tusk every bit a weapon, for opening breathing holes in ocean ice, in feeding, as an acoustic organ and as a secondary sex activity grapheme. The leading theory has long been that the narwhal tusk serves as a secondary sex activity graphic symbol of males, for nonviolent cess of hierarchical status on the footing of relative tusk size.^[26] Even so, detailed analysis reveals that the tusk is a highly innervated sensory organ with millions of nervus endings connecting seawater stimuli in the external bounding main environment with the brain.^{[27] [28] [29] [30]} The rubbing of tusks together past male narwhals is idea to exist a method of communicating information about characteristics of the water each has travelled through, rather than the previously assumed posturing brandish of aggressive male person-to-male rivalry.^[29] In August 2016, drone videos of narwhals surface-feeding in Tremblay Audio, Nunavut showed that the tusk was used to tap and stun small Arctic cod, making them easier to catch for feeding.^{[31] [32]} The tusk cannot serve a critical function for the animate being'south survival, as females — which generally do non have tusks — typically alive longer than males. Therefore, the general scientific consensus is that the narwhal tusk is a sexual trait, much like the antlers of a stag, the mane of a lion, or the feathers of a peacock.^[33]

Vestigial teeth

The tusks are surrounded posteriorly, ventrally and laterally by several small vestigial teeth which vary in morphology and histology.^[nineteen] These teeth can sometimes exist extruded from the bone, but mainly reside inside open up tooth sockets in the narwhal's snout alongside the tusks.^{[xix] [34]} The varied morphology and beefcake of small teeth indicate a path of evolutionary obsolescence,^[xix] leaving the narwhal'due south oral fissure toothless.^[34]

Genome

A ii.3 GB genome sequence has been assembled from multiple Illumina libraries. The genome consists of 37.9% repetitive elements and encodes 21,785 poly peptide-coding genes (like to many other mammals). The genome volition help to place the narwhal both into the evolutionary context of other whales but also will help to empathize the development and embryonic development of features such equally the hitting tusk and its sexual dimorphism.^[35]

Distribution

The narwhal is found predominantly in the Atlantic and Russian areas of the Arctic Ocean. Individuals are ordinarily recorded in the Canadian Arctic Archipelago,^[31] such as in the northern part of Hudson Bay, Hudson Strait, Baffin Bay; off the east coast of Greenland; and in a strip running due east from the northern end of Greenland round to eastern Russian federation (170° Due east). Land in this strip includes Svalbard, Franz Joseph State and Severnaya Zemlya.^[8] The northernmost sightings of narwhal have occurred north of Franz Joseph Land, at about 85° North latitude.^[8] Near of the world'due south narwhals are concentrated in the fjords and inlets of Northern Canada and western Greenland.

Behaviour

Narwhals commonly congregate in groups of about five to ten and sometimes up to 20 individuals outside the summer. Groups may be "nurseries" with only females and young, or can contain only post-dispersal juveniles or adult males ("bulls"), simply mixed groups can occur at any time of year.^[fifteen] In the summer, several groups come together, forming larger aggregations which can contain from 500 to over 1000 individuals.^[xv]

At times, a bull narwhal may rub its tusk with another bull, a display known as "tusking"^{[28] [36]} and thought to maintain social dominance hierarchies.^[36] However, this behaviour may exhibit tusk employ every bit a sensory and communication organ for sharing information most water chemistry sensed in tusk microchannels.^{[27] [28]}

Migration

Narwhals exhibit seasonal migrations, with a high fidelity of render to preferred, ice-gratis summering grounds, usually in shallow waters. In summertime months, they motility closer to coasts, often in pods of ten–100. In the winter, they move to offshore, deeper waters under thick pack ice, surfacing in narrow fissures in the sea ice, or leads.^[37] As spring comes, these leads open up up into channels and the narwhals render to the coastal bays.^[38] Narwhals from Canada and West Greenland winter regularly in the pack ice of Davis Strait and Baffin Bay along the continental gradient with less than 5% open water and loftier densities of Greenland halibut.^[39] Feeding in the winter accounts for a much larger portion of narwhal free energy intake than in the summer.^{[39] [37]}

Diet

Narwhals have a relatively restricted and specialized diet. Their prey is predominantly equanimous of Greenland halibut, polar and Arctic cod, cuttlefish, shrimp and armhook squid. Boosted items plant in stomachs take included wolffish, capelin, skate eggs and sometimes rocks, accidentally ingested when whales feed near the bottom.^{[xv] [39] [37] [36]} Due to the lack of well-developed dentition in the mouth, narwhals are believed to feed by swimming towards casualty until it is within close range and so sucking it with considerable force into the oral fissure. It is thought that the beaked whales, which take similarly reduced dentition, also suck up their prey.^[twoscore] The distinctive tusk is used to tap and stun small prey, facilitating a catch.^{[31] [32]}

Narwhals take a very intense summer feeding society. One report published in the Canadian Journal of Zoology tested 73 narwhals of different age and gender to see what they ate. The individuals were from the Pond Inlet and had their stomach contents tested from June 1978 until September 1979. The report plant in 1978 that the Arctic cod (Boreogadus saida) fabricated up about 51% of the diet of the narwhals, with the adjacent almost common animal beingness the Greenland halibut (Reinhardtius hippoglossoides), consisting of 37% of the weight of their diet. A year later, the percentages of both animals in the diet of narwhals had changed. Arctic cod represented 57% and Greenland halibut 29% in 1979. The deep-water fish – halibut, redfish (Sebastes marinus) and polar cod (Arctogadus glacialis) – were found primarily in the diet of the males, which means that the narwhals tin can swoop deeper than 500 1000 (1,640 ft) below ocean level. The report found that the dietary needs of the narwhal did non differ amongst genders or ages.^[41]

Diving

Upside-down pond behaviour of narwhals

Narwhal tail fluke

When in their wintering waters, narwhals make some of the deepest dives recorded for a marine mammal, diving to at least 800 metres (2,620 feet) over 15 times per day, with many dives reaching 1,500 metres (four,920 feet). Dives to these depths terminal around 25 minutes, including the time spent at the lesser and the transit down and back from the surface.^[42] Swoop times can too vary in fourth dimension and depth, based on local variation between environments, as well every bit seasonality. For instance, in the Baffin Bay wintering grounds, narwhals farther due south announced to exist spending most of their fourth dimension diving to deeper depths along the steep slopes of Baffin Bay, suggesting differences in habitat construction, prey availability, or innate adaptations betwixt subpopulations.^[42] Curiously, whales in the deeper northern wintering ground have access to deeper depths, yet brand shallower dives. Because vertical distribution of narwhal prey in the water cavalcade influences feeding behaviour and dive tactics, regional differences in the spatial and temporal patterns of prey density, equally well as differences in prey assemblage, may be shaping winter foraging behaviour of narwhals.

Communication

Every bit near toothed whales, narwhals use sound to navigate and hunt for food. Narwhals primarily vocalise through "clicks", "whistles" and "knocks", created by air movement between chambers near the blow-hole. These sounds are reflected off the sloping front of the skull and focused by the animate being'southward melon, which can be controlled by musculature. Echolocation clicks are primarily produced for prey detection and for locating obstacles at brusque distances. It is possible that private "bangs" are capable of disorienting or incapacitating prey, making them easier to hunt, just this has not been verified. They also emit tonal signals, such as whistles and pulsed calls, that are believed to have a communication function.^[43] The calls recorded from the same herd are more similar than calls from dissimilar herds, suggesting the possibility of grouping or individual-specific calls in narwhals. Narwhals may also adjust the duration and the pitch of their pulsed calls to maximise sound propagation in varying acoustic environments ^[44] Other sounds produced by narwhals include trumpeting and squeaking door sounds.^[9] The narwhal song repertoire is like to that of the closely related beluga, with comparable whistle frequency ranges, whistle duration and repetition rates of pulse calls, notwithstanding beluga whistles may have a higher frequency range and more diversified whistle contours.^[43]

Breeding and early life

Females first bearing calves when six to viii years quondam.^[nine] Adult narwhals mate in Apr or May when they are in the offshore pack ice. Gestation lasts for 14 months and calves are born between June and August the following year. As with most marine mammals, simply a single young is built-in, averaging i.6 metres (v.ii feet) in length and white or light grey in colour.^{[nine] [45]} During summer population counts forth different littoral inlets of Baffin Isle, calf numbers varied from 0.05% to 5% of the total numbering from 10,000 to 35,000 narwhals, indicating that higher calf counts may reflect calving and plant nursery habitats in favourable inlets.^[45] Hybrids have been documented between the narwhal and beluga (specifically a beluga male and a narwhal female), as ane, perhaps even as many every bit 3, were killed and harvested during a sustenance chase. Whether or not these hybrids could breed remains unknown. The unusual dentition seen in the single remaining skull indicates the hybrid hunted on the seabed, much every bit walruses do, indicating feeding habits dissimilar from those of either parent species.^{[46] [47]}

Newborn calves begin their lives with a thin layer of blubber which thickens as they nurse their mother'southward milk which is rich in fat. Calves are dependent on milk for around 20 months.^[ix] This long lactation period gives calves fourth dimension to learn skills needed for survival during maturation when they stay inside 2 torso lengths of the female parent.^{[9] [45]}

Lifespan and mortality

Narwhals can live an average of 50 years, however research using aspartic acid racemization from the lens of the eyes suggests that narwhals can alive to exist as old as 115 ± ten years and 84 ± nine years for females and males, respectively ^[48] Bloodshed often occurs when the narwhals suffocate afterward they fail to get out earlier the surface of the Arctic waters freeze over in the late autumn.^{[15] [49]} Equally narwhals need to breathe, they drown if open water is no longer accessible and the water ice is likewise thick for them to break through. Maximum aerobic swimming distance between breathing holes in ice is less than one,450 m (4,760 ft) which limits the use of foraging grounds and these holes must be at least 0.5 m (1.6 ft) broad to allow an developed whale to breathe.^[50] The last major entrapment events occurred when at that place was little to no air current. Entrapment tin affect as many equally 600 individuals, nigh occurring in narwhal wintering areas such as Disko Bay. In the largest entrapment in 1915 in West Greenland, over 1,000 narwhals were trapped under the ice.^[51]

Despite the decreases in sea ice encompass, there were several large cases of ocean ice entrapment in 2008–2010 in the winter close to known summering grounds, two of which were locations where there had been no previous cases documented.^[49] This suggests later departure dates from summering grounds. Sites surrounding Greenland experience advection (moving) of bounding main ice from surrounding regions by wind and currents, increasing the variability of ocean ice concentration. Due to strong site fidelity, changes in weather and ice conditions are not always associated with narwhal motion toward open water. More information is needed to determine the vulnerability of narwhals to sea ice changes. Narwhals tin can also die of starvation.^[15]

Predation and hunting

Major predators are polar bears, which attack at breathing holes mainly for immature narwhals and Greenland sharks.^{[15] [52]} Killer whales (orcas) group together to overwhelm narwhal pods in the shallow water of enclosed bays,^[53] in one case killing dozens of narwhals in a unmarried attack.^[54] To escape predators such every bit orcas, narwhals may use prolonged submergence to hide nether ice floes rather than relying on speed.^[50]

Beluga and narwhal catches

Humans chase narwhals, ofttimes selling commercially the skin, carved vertebrae, teeth and tusk, while eating the meat, or feeding information technology to dogs. Virtually 1,000 narwhals per year are killed, 600 in Canada and 400 in Greenland. Canadian harvests were steady at this level in the 1970s, dropped to 300–400 per twelvemonth in the late 1980s and 1990s and rose again since 1999. Greenland harvested more, 700–900 per twelvemonth, in the 1980s and 1990s.^[55]

Tusks are sold with or without carving in Canada^{[56] [57]} and Greenland.^[58] An average of one or two vertebrae and one or two teeth per narwhal are carved and sold.^[56] In Greenland the pare (muktuk) is sold commercially to fish factories,^[58] and in Canada to other communities.^[56] One guess of the almanac gross value received from narwhal hunts in Hudson Bay in 2013 was CA$530,000 for 81 narwhals, or CA$6,500 per narwhal. Nonetheless the cyberspace income, after subtracting costs in time and equipment, was a loss of CA$vii per person. Hunts receive subsidies, only they continue as a tradition, rather than for the money and the economic assay noted that whale watching may be an alternating revenue source. Of the gross income, CA$370,000 was for skin and meat, to replace beef, pork and chickens which would otherwise be bought, CA$150,000 was received for tusks and carved vertebrae and teeth of males and CA$10,000 was received for carved vertebrae and teeth of females.^[56]

Conservation issues

Narwhals are ane of many mammals that are being threatened by human actions.^[59] Estimates of the world population of narwhals range from effectually 50,000 (from 1996)^[38] to around 170,000 (compilation of various sub-population estimates from the years 2000–2017).^[4] They are considered to exist most threatened and several sub-populations accept testify of decline. In an effort to support conservation, the European Union established an import ban on tusks in 2004 and lifted it in 2010. The Us has forbidden imports since 1972 under the Marine Mammal Protection Act.^[59] Narwhals are difficult to keep in captivity.^[28]

Male narwhal captured and satellite tagged

Inuit people chase this whale species legally, every bit discussed above in Predation and hunting. Narwhals have been extensively hunted the aforementioned way equally other sea mammals, such as seals and whales, for their large quantities of fatty. Almost all parts of the narwhal, meat, peel, blubber and organs are consumed. Muktuk, the name for raw skin and blubber, is considered a delicacy. 1 or two vertebrae per animal are used for tools and art.^{[56] [8]} The pare is an important source of vitamin C which is otherwise hard to obtain. In some places in Greenland, such as Qaanaaq, traditional hunting methods are used and whales are harpooned from handmade kayaks. In other parts of Greenland and Northern Canada, high-speed boats and hunting rifles are used.^[8]

During growth, the narwhal accumulates metals in its internal organs. One study found that many metals are depression in concentration in the blubber of narwhals and high in the liver and the kidney. Zinc and cadmium are institute in college densities in the kidney than the liver and lead, copper and mercury were found to be the contrary. Certain metals were correlated with size and sex. During growth, it was found that mercury accumulated in the liver, kidney, muscle and blubber and that cadmium settled in the blubber.^[60]

Narwhals are one of the nigh vulnerable Arctic marine mammals to climate change^{[38] [61]} due to altering body of water ice coverage in their environs, peculiarly in their northern wintering grounds such as the Baffin Bay and Davis Strait regions. Satellite information collected from these areas shows the amount of bounding main ice has been markedly reduced.^[62] Narwhals' ranges for foraging are believed to be patterns developed early on in their life which increase their ability to gain necessary nutrient resources during winter. This strategy focuses on strong site fidelity rather than private level responses to local prey distribution and this results in focal foraging areas during the winter. As such, despite irresolute conditions, narwhals will continue returning to the aforementioned areas during migration.^[62] Despite its vulnerability to bounding main ice change, the narwhal has some flexibility when it comes to sea ice and habitat option. It evolved in the late Pliocene and then is moderately accustomed to periods of glaciation and environmental variability.^[63]

An indirect danger for narwhals associated with changes in body of water water ice is the increased exposure in open h2o. In 2002 in that location was an increment in narwhal catches by hunters in Siorapaluk that did not appear to exist associated with increased endeavour,^[64] implying that climate change may exist making the narwhal more vulnerable to harvesting. Scientists urge cess of population numbers with the consignment of sustainable quotas for stocks and the collaboration of management agreements to ensure local acceptance. Seismic surveys associated with oil exploration have likewise disrupted normal migration patterns which may also exist associated with increased sea ice entrapment.^[65]

Cultural depictions

In fable

The head of an Inuit lance made from a narwhal tusk with a meteorite iron blade (British Museum)

In Inuit legend, the narwhal's tusk was created when a adult female with a harpoon rope tied around her waist was dragged into the ocean subsequently the harpoon had struck a large narwhal. She was transformed into a narwhal and her hair, which she was wearing in a twisted knot, became the characteristic spiral narwhal tusk.^[66]

Some medieval Europeans believed narwhal tusks to be the horns from the legendary unicorn.^{[67] [68]} As these horns were considered to have magic powers, such as neutralising poison and curing affective, Vikings and other northern traders were able to sell them for many times their weight in gilded.^[69] The tusks were used to make cups that were thought to negate any poison that may have been slipped into the drink. A narwhal tusk exhibited at Warwick Castle is according to legend the rib of the mythical Dun Cow.^[70] In 1555, Olaus Magnus published a cartoon of a fish-like creature with a horn on its forehead, correctly identifying it as a "Narwal".^[67] During the 16th century, Queen Elizabeth I received a narwhal tusk worth ten,000 pounds sterling—the 16th-century equivalent cost of a castle (approximately £ane.five–2.5 million in 2007, using the retail price index^[69])–from Sir Humphrey Gilbert, who proposed that the tusk was from a "sea-unicorne". The tusks were staples of the cabinet of curiosities.^[67] European knowledge of the tusk's origin adult gradually during the Age of Exploration, every bit explorers and naturalists began to visit Arctic regions themselves.

In literature and fine art

The narwhal was one of 2 possible explanations of the giant sea miracle written by Jules Verne in his 1870 novel Twenty Thousand Leagues Under the Sea. Verne thought that it would be unlikely that there was such a gigantic narwhal in existence. The size of the narwhal, or "unicorn of the sea", every bit establish by Verne, would have been 18.3 chiliad (60 ft). For the narwhal to accept caused the phenomenon, Verne stated that its size and forcefulness would have to increase past five or ten times.^[71]

Herman Melville wrote a section on the narwhal (written as "narwhale") in his 1851 novel Moby-Dick, in which he claims a narwhal tusk hung for "a long period" in Windsor Castle afterward Sir Martin Frobisher had given it to Queen Elizabeth. Another claim he made was that the Danish kings made their thrones from narwhal tusks.^[72]

Gallery

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  A pod off Greenland

Run across besides

• List of cetaceans

References

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Further reading

• Ford, John; Ford, Deborah (March 1986). "Narwhal: Unicorn of the Arctic Seas". National Geographic. Vol. 169, no. 3. pp. 354–363. ISSN 0027-9358. OCLC 643483454.
• K. P. Heide-Jorgensen. "Narwhal", in Encyclopedia of Marine Mammals, Perrin, Wursig and Thewissen eds. ISBN 0-12-551340-2
• Groc, Isabelle. "Chase for the body of water unicorn", New Scientist feature article, Issue 2956, 15 Feb 2014 [i]

External links

• Flower, W.H. (1911). "Narwhal". Encyclopædia Britannica. Vol. 19 (11th ed.). p. 243.
• Biological science and ecology of narwhals, NOAA
• Narwhal Discoveries
• Voices in the Sea – Sounds of the Narwhal

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Source: https://en.wikipedia.org/wiki/Narwhal

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