Discovering the Narwhal
Unicorn of the Sea
Lara Arbach
12/3/2009
Narwhal, Monodon monoceros, and Qilalugaq qernartaq are three descriptions of an arctic
whale characterized by its legendary tusk (Nweeia and Meehan). Narwhal translates from Old Norse, the
prefix “Nar” means “corpse” and “hval” means “whale” (Laidre and Heide-Jørgensen). Thus “corpse-
like,” the animal’s grayish, mottled pigmentation resembles that of a drowned sailor (Narwhal). The
narwhal was one of the many species originally described by Linneaus in 1758 in his book, Systema
Naturae (Narwhal). Carl Linnaeus was a Swedish botanist, physician, and zoologist who laid the
foundations for the modern scheme of binomial nomenclature. He is known as the father of modern
taxonomy, and his main contribution to science was to establish conventions for the naming of living
organisms that became universally accepted in the scientific world (Carl Linneaus). He documented the
species name for the narwhal’s most unique feature, its unicorn-like single tusk found on most males
(Nweeia and Meehan); Monodon monoceros, means “one tooth, one horn” (Laidre and Heide-
Jørgensen). The Inuit name, Qilalugaq qernartaq, translates to mean “the one that points to the sky,”
describing the narwhal’s unique behavior of pointing the tusk straight upward out of the water (Nweeia
and Meehan).
The Inuit people of Northern Canada and Greenland have respected the ancient narwhals for
thousands of years, and have honored them in their traditions and culture. An Inuit legend of how the
narwhal came to be started with a wicked woman who lived with her daughter and her blind son. As the
son got older, his sight improved, even though the mother tried to convince him of his helpless state.
Time passed and an old man came to the house for a visit, and told the young girl how she could help
her brother regain his sight. In the spring, he told them to watch for a red throated loon at a nearby lake
who would swim trustingly towards them. Once the loon was close enough, the blind brother wrapped
his arms around the loon's neck and took him to the bottom of the lake. Once they emerged from the
water, his sight returned. The loon told the young man not to mention his regained sight until later in
the summer when the loon would send a pod of belugas to their campsite. When summer came and the
ice began to break, the belugas began to move. One morning, a pod was closer to land than usual. The
young man grabbed his harpoon and told his sister to accompany him to help him aim. They went to the
shoreline, and the mother seeing the son with a harpoon became concerned and followed them. Once
she was close to them, the son gave the end of the line from the harpoon to his mother, asking her to tie
it around her waist to hold the harpooned animal. The son aimed for the largest whale and harpooned
it. The mother was cast into the sea, and as she submerged into the water she spiraled around the line
transforming into the whale, with her long hair twisting in the water until it became the characteristic
spiral narwhal tusk (Nweeia and Meehan).
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The narwhal has been a long fascination for sea explorers and scientists by its unique physical
characteristics. Infant narwhals, called calves, are gray or dark bluish-gray. After two years, the skin
becomes more mottled with overlapping white patches, and the gray color becomes more blackened.
Adults are white on the ventral side, and light brown and mottled on the dorsal side (Nweeia and
Meehan). The patchy discoloration resembles livor mortis; a settling of blood underneath the skin when
death occurs (Lambert). Older adults have only a narrow dark triangular band extending from the back
of the neck at its widest portion to a point ending on the midline of the back (Nweeia and Meehan).
About four inches of fat insulates the narwhal from the cold Arctic waters (Narwhal: Arctic Animals).
Males can reach a length of five meters (approximately 16 feet) and weigh up to 1,600 kg (about 3,500
pounds). Females are somewhat smaller, reaching a length of four meters (approximately 13 feet) and
1,000 kg (2,200 pounds) (Laidre and Heide-Jørgensen). Compared to other cetaceans, marine mammals
such as whales and dolphins, narwhals have a small head, blunt snout, short rounded flippers, and
convex rather than concave tail flukes. They have no dorsal fin, but have a ridge about five centimeters
high that runs along the posterior end on the dorsal side, which measures 60 - 90 centimeters (24 – 35
inches) long (Narwhal, Monodon monoceros). There is currently no reliable method for determining the
age of narwhal, (Nweeia and Meehan) however, narwhals have been recorded to live 50 years or more
(Laidre and Heide-Jørgensen).
The narwhal is a gregarious species commonly found in groups, or “pods,” sometimes up to 20
individuals varying combinations of males, females, and calves (Narwhal Whales), but are mostly found
in groups of three to eight, which are regularly segregated by sex. (Laidre and Heide-Jørgensen). The
male narwhal reaches sexual maturity at eight to nine years old, and the female at four to seven years
old. Narwhal are seasonally estrous, typically breed in mid-April (Narwhal Whales), and mate in the
water belly to belly (Narwhal, Monodon monoceros). The female is able to give birth to a single calf once
every three years with a 15-month gestation period (Narwhal Whales), however, in rare cases the birth
of twins have been recorded. Calves are born tail first and measure 1.5 - 1.7 meters (approximately 5
feet) long and weigh 80 kg (176 pounds), with about a 25 millimeter thick layer of blubber (Narwhal,
Monodon monoceros). Narwhal calves are usually born in July, are rarely born outside deep bays and
inlets, and remain with the female for up to 20 months after they are born. Newborn calves are dark
blue-gray, but as they mature the back transforms to an olive brown and begins to develop the mottled
spotting, which is most often seen in adult narwhals.
One of the most distinguished characteristic traits of the narwhal is a tusk protruding from its
forehead. The narwhal is an odontocete, a toothed whale, but is different from other toothed whales
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because it has no teeth in its mouth (Laidre and Heide-Jørgensen). Calves initially develop six pairs of
maxillary teeth and two pairs of mandibular teeth. Only one pair from the maxillary jaw develops and
the others are vestigial, or functionless (Nweeia and Meehan). The male develops a long, straight tusk
that projects two to three meters (roughly nine feet) from its head, grows in a counter-clockwise spiral,
and can weigh up to 10 kg (22 pounds) (Laidre and Heide-Jørgensen). The tusk is the left incisor tooth
protruding out of the upper left side of the jaw through the lips, and is variable in length, girth,
morphology, wear, and coloration depending on the whale and age (Nweeia and Meehan). The tusk is
flexible, able to bend about a foot in any direction without breaking (Lambert). The right tooth remains
embedded in the jaw and measures roughly one foot (Nweeia and Meehan). About one in 500 males can
produce two tusks, which occurs when the right incisor tooth also grows out (Narwhal). On rare
occasions, females can produce a tusk, which are shorter, straighter, and have a more regularly defined
morphology (Nweeia and Meehan). The narwhal tooth is the only straight tusk in the world, and also
one of the only spiral tooth (Lambert).
Narwhals can be found in the Atlantic portion of the Arctic Ocean; concentrating in the Canadian
high Arctic, Baffin Bay, Davis Straight, and northern Hudson Bay. They can also be found in less numbers
near Alaska, and in the Greenland Sea extending to Svalbard to Severnaya Zemlya off Russia (Nweeia
and Meehan). The most northern sighting of narwhals has occurred north of Franz Joseph Land, at about
85° North latitude (Narwhal). Narwhals are one of the northernmost cetacean species with a smaller
range. They stay near the loose pack ice, where they maintain breathing holes, and prefer deep water,
migrating with the seasonal advance and retreat of the ice (Narwhal, Monodon monoceros). In the
summer, they occupy deep bays and fjords in the Canadian high Arctic and Greenland. During the
summer migratory season, smaller groups combine with other groups to form large pods. As winter
approaches, narwhals migrate into the pack ice of Baffin Bay, the northern Davis Strait, and adjacent
waters. During months when ice is forming, narwhals are in danger of being trapped beneath the ice.
Such entrapments are known to have killed hundreds of narwhals. Narwhals have predictable migration
patterns and are creatures of habit. Even though they spend a large amount of time offshore far from
humans, they still move along the coast, and pass certain promontories, bays, or fjords at precisely the
same time each year (Laidre and Heide-Jørgensen).
Most notable of the narwhal’s adaptations is their ability to perform deep dives. In summer,
narwhals often dive to depths between 30 and 300 meters (approximately 98 – 980 feet), although they
spend most of their time at or below 50 meters (Narwhal). In fall, dive depths and durations increase
when narwhals migrate towards their wintering grounds. When at their wintering grounds, they stay in a
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fairly limited area for six months and make small movements with the shifting leads and cracks in the
pack ice (Laidre and Heide-Jørgensen). Narwhals typically dive to at least 800 meters (around 2,600 feet)
between 18 and 25 times per day, every day for six months. Many of these dives are even deeper of at
least 1,500 meters (roughly 4,900 feet) (Narwhal); some of the deepest diving ever recorded for a
marine mammal. Dives to these depths last around 25 minutes which includes the transit down, time
spent at the bottom, and back to the surface. In addition to making remarkably deep dives, narwhals
also spend a large amount of their time below 800 meters greater than three hours per day. This is an
incredible amount of time at a depth with an enormous amount of pressure exceeding 2,200 PSI
(pounds per square inch) and lack of air, which requires special adaptations for survival. Narwhals have a
compressible rib cage which is flexible and can be squeezed as the water depth increases. They have a
high concentration of myoglobin in their muscles (a molecule which binds oxygen); twice as much as
some seal species and eight times as much as terrestrial mammals, even those specialized in fast
running. An average-sized narwhal can carry 70 liters of oxygen in its lungs, blood, and muscles meeting
oxygen demands for more than 20 minutes underwater at swim speeds of one meter/second.
Furthermore, the narwhal does not have fast-twitch fibers in its skeletal muscles (like a dolphin), but
instead has muscles suited for endurance swimming (less oxygen demanding). During its dive, a narwhal
can save oxygen by shutting off blood flow to selected organs or non-critical body parts. Finally,
narwhals have streamlined bodies and can glide easily through the water column towards the bottom.
This helps minimize oxygen consumption to work the muscles and ultimately saves energy (Laidre and
Heide-Jørgensen).
It is thought that narwhals produce sounds in their nasal passages (Hebridean Whale and
Dolphin Trust). The melon, a fatty organ located at the cranial portion of the head, focuses these sounds
into a beam before sending them out. The sound waves travel until they hit something, at which point
the echoes bounce back to the whale (Lambert). The whale receives these echoes either in the lower
jaw or directly in the skull, depending on the frequency of the sound (Hebridean Whale and Dolphin
Trust). Each sound wave has a different range of frequencies, depending on what the whales need
echolocation for; low-frequency sounds go farther, while high-frequency sounds are suited to short
distances (Lambert). Narwhals whistle and produce a combined pulsed/tonal sound (Institution). A wide
variation of clicks and whistles are used, with click rates varying from three to 150 clicks per second
(Nweeia and Meehan). Researchers suspect the narwhals use echolocation to communicate as well as to
hunt (Lambert).
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Identifying what narwhals eat has proven to be a difficult task for researchers. Narwhals
navigate polynyas, which are pools of open water in otherwise iced-over environments. The polynyas
are rich in organisms, such as phytoplankton and copepods, that serve as the feeding grounds for
biodiverse marine animals (Lambert). However, narwhals mostly prefer waters far offshore covered in
sea ice where they eat at great depths in complete darkness. Because of this, no direct observations of
narwhal feeding has ever been made. An alternate method is used to discover the eating habits, by
examining the stomachs of dead whales. The results of examining hundreds of narwhal stomachs over
the past ten years have identified patterns implying they are carnivores, and have a very restricted and
specialized diet. Narwhals eat only a few prey species; primarily Greenland halibut, the polar and Arctic
cod, shrimp, and Gonatus squid. Occasional exceptions have been wolffish, capelin, skate eggs, and
sometimes rocks are accidentally ingested when the whales feed near the bottom (Laidre and Heide-
Jørgensen).
Narwhals change their diet seasonally. In winter, they feed intensively on Greenland halibut or
Gonatus squid. They eat a lot of Greenland halibut, because the bulk of their energy uptake occurs on
the wintering grounds in Baffin Bay where the narwhals spend more than half of the year. The many
deep dives also indicate the narwhals feed mostly on the bottom. The summer ice-free season, between
July and September, is not used for intense feeding and whales have very little in their stomachs except
for the Arctic cod. The narwhal’s concentrated winter feeding period is likely an adaptation to relatively
low productivity in the high arctic summering areas, or a behavioral trait to avoid competition with
lower latitude whales feeding in summer (Laidre and Heide-Jørgensen).
The purpose of having such a large tooth has been discussed by scientists for centuries. Many
suggestions have been made, such as narwhals using their tusk to dig up the seafloor, spear prey,
making holes in sea ice, or to determine sea ice thickness. It cannot serve a critical function for survival,
because females rarely have a tusk and live longer than males (Laidre and Heide-Jørgensen). It is
thought to play a strong role in the mating activity of the whale, as they have been seen with their tusks
crossed to possibly determine dominance. Additionally, the tusk is known to experience a growth-spurt
at sexual maturity in males; this has been interpreted as suggesting there is a possible breeding function
tied into the narwhal tusk (Narwhal Whales). During the summer in the northern Canadian high Arctic
bays and fjords, male narwhals can be seen carefully crossing their tusks as though they are practicing
sword fighting, called “tusking,” and making a strange, sad whistle. Such behavior might help determine
social rank and maintain dominance hierarchies, similar to the antlers of a stag. Narwhals have not been
observed using their tusk for fighting or other aggressive behavior (Laidre and Heide-Jørgensen).
[6]
Often associated with the mythical unicorn, the narwhal’s tooth has found its way into the
books of scientific rarities and fantasy tales (Nweeia and Meehan). Some medieval Europeans believed
narwhal tusks to be the horns from the legendary unicorn. As these horns were considered to have
magic powers, such as the ability to cure poison and melancholia, Vikings and other northern traders
were able to sell them for many times their weight in gold. The tusks were used to make cups that were
thought to negate any poison that may have been slipped into the drink. During the 16th century,
Queen Elizabeth received a carved and bejeweled narwhal tusk worth £10,000, around the cost of a
castle (approximately £1.5 million; $2.5 million worth in 2007) (Narwhal).
The truth of the tusk's origin developed gradually during the Age of Exploration, as explorers
and naturalists began to visit Arctic regions themselves. In 1555, Olaus Magnus, Swedish ecclesiastic and
writer, published a drawing of a fish-like creature with a horn on its forehead, correctly identifying it as a
narwhal. The author, Herman Melville wrote a section on the narwhal in Moby Dick, in which he claims
that a narwhal tusk hung for “a long period” in Windsor Castle after Sir Martin Frobisher had given it to
Queen Elizabeth (Narwhal). Artists know the narwhal for its unique association to the famous Unicorn
Tapestries; six from the Lady and the Unicorn hanging at the Cluny Museum in Paris and seven from the
Hunt of the Unicorn at the Cloisters Museum in New York, are among the most renowned and well
known works of art of all time. The tooth is revered by many cultures around the world. In Japan, two
crossed narwhal teeth adorn the entrance to the Korninkaku Palace. In Denmark multiple teeth decorate
the frame of the Danish throne. The royal scepter in England is made from the rare tusk. The unicorn
and the narwhal tooth continue as an endless source of fascination in modern culture (Nweeia and
Meehan).
The Narwhal Tusk Research, founded in 2000, is a multinational collaboration with an
interdisciplinary approach that crosses the borders of biologic, chemical, physical, and social science to
discover the purpose and function of the erupted tusk of the narwhal. 27 Institutions worldwide and
over 48 scientists with a myriad of backgrounds in cellular biology, histology, anatomy, marine mammal
science, dental medicine, evolutionary genetics, and mathematics, have combined their insights with 32
experienced Inuit elders. The Inuit elders have extensive skills as hunters and guides from the Eastern
Canadian high Arctic and Western Greenland are continuing to provide traditional knowledge, guide,
and direct current findings and past studies about the behavioral and social characteristics of the
narwhal and its tusk (Nweeia and Meehan).
The Tusk Research was successfully able to discover the results of the function of the tusk, as
revealed by Dr. Martin Nweeia, a clinical instructor at the Harvard School of Dental Medicine (Lambert).
[7]
The bottom end of the tusk appears clean and polished, however, the remaining tusk is often covered in
algae. The tusks are made up of an outer layer of cement, an inner layer calcareous hard tooth material
called dentine, and a pulp cavity rich in blood that holds the tusk in place. Narwhals often break tusks,
however, they are able to repair the damage with new dentine growth (Narwhal, Monodon monoceros).
According to a Press Release from the Harvard Medical School dated December 13, 2005:
"Dr. Nweeia has discovered that the narwhal's tooth has hydrodynamic sensor capabilities. Ten
million tiny nerve connections tunnel their way from the central nerve of the narwhal tusk to its
outer surface. Though seemingly rigid and hard, the tusk is like a membrane with an extremely
sensitive surface, capable of detecting changes in water temperature, pressure, and particle
gradients. Because these whales can detect particle gradients in water, they are capable of
discerning the salinity of the water, which could help them survive in their Arctic ice
environment. It also allows the whales to detect water particles characteristic of the fish that
constitute their diet. There is no comparison in nature and certainly none more unique in tooth
form, expression, and functional adaptation" (Narwhal, Monodon monoceros).
This sensitive quality does seem to cancel out some of the theories about the tusk, such as the idea male
narwhals use them to duel, although some scientists still argue the tusk is a way of establishing
dominance. Narwhals do touch tusks, but observers have reported them to be nonviolent. Researchers
are unsure, but suggest perhaps it is a form of communication. One theory which still holds is the tusk is
used as a sex characteristic for mating purposes (Lambert).
About 50,000 narwhals are estimated to live in Greenland and Canada, but recent research
suggests the numbers have declined by about 6% since the 1980’s. Three possible causes have been
suggested: hunting, development of inshore fisheries, and climate change (Laidre and Heide-Jørgensen).
Their natural enemies include orcas, polar bears, and rarely walruses. Narwhals have been traditionally
hunted by the Inuits, who are allowed to hunt a certain number of narwhals a year in accordance with
their traditions and culture (Lambert). The Canadian government instituted the Narwhal Protection
Regulation under the Fisheries Act in 1971. This made hunting narwhals illegal for anyone other than the
Inuits. There is a catch limit of five narwhals a year per subsistence hunter, and hunters are required to
utilize every part of the narwhal (Narwhal - Wildlife). Almost all parts of the narwhal, meat, skin, blubber
and organs, are consumed (Narwhal). Inuits dine on the top layer of skin and blubber, called muktuk or
maktaaq, for vitamin C, a scarce commodity in the Arctic (Lambert). The narwhal’s bones are used for
tools and art (Narwhal), and their tusks are also valued commercially in Canada and Greenland,
however, international efforts to control the global ivory trade may have reduced tusk sales in recent
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years (Laidre and Heide-Jørgensen). The narwhal has been deemed particularly vulnerable to climate
change, due to their narrow geographical range and specialized diet (Narwhal). Because narwhals are
wedded to their pack ice environment, changes in sea ice have a huge impact on their migration
patterns and survival. If the ice is too thick, narwhals can get trapped under it and cannot surface to
breathe. If the ice is too thin, predators may find it easier to hunt them and their prey may move
elsewhere (Lambert).
As a consequence of the whale’s elusiveness, scientists can only identify a few infestations the
narwhal can harbor, such as whale lice located on the base of the tusk, and certain nematodes, or
roundworms (Narwhal: Arctic Animals). Narwhals can also be susceptible to new diseases, as a result of
climate change. Ole Nielson, a researcher with the Federal Department of Fisheries and Oceans, is
concerned that climate change may introduce new diseases that could decimate the North’s narwhal
and beluga whale populations. Diseases such as distemper and brucellosis could trigger dramatic die-offs
among northern whale groups. Distemper, similar to the disease that affects household pets, can cause
seizures and ultimately death in aquatic mammals. As the oceans warm with climate changes, animals
known to carry the disease, such as dolphins, will come north. The disease produced by bacteria, can
cause weight loss in animals, infertility, and lameness. It can also spread to humans, which is why
Nielson is recommending whale harvesters take care when butchering animals. While none of the
narwhals or beluga whales Nielson have tested has distemper, he said those animals would
be defenseless against the disease if they came into contact with it (CBC News - North). About 6% of the
Arctic beluga whale samples tested up to the mid-1990’s was positive for brucellosis, a disease that can
cause reproductive failure and late abortions. Since then, the infection rate has been rising. At best,
natural immunity will protect most species from diseases that have until now been kept in check by cold
temperatures, or by climatic conditions that prevent disease-carrying animals from expanding their
range northward (Disease, the Scariest Threat).
Integrating scientific needs and objectives with habitat preferences and diving abilities of
narwhals will allow for new investigations to be made. Due to harsh winter conditions in the Arctic,
scientists have employed the use of narwhals as part of a research project to determine global warming
conditions in the waters, and also provide researchers the opportunity to observe narwhals in their
winter habitat. The purpose of the exploration project is to improve understanding of climatic changes
occurring in an offshore ecosystem of Baffin Bay, and how these changes may affect narwhal
populations who are part of that ecosystem. Satellite tags are attached to narwhals inserted through the
dorsal ridge on the whale’s back. These satellite-linked, time-depth-temperature recorders track
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narwhal whale movements, diving behavior, and ocean temperature structure in Baffin Bay. The
instruments collect water column temperature profiles in the pack ice to more than 1,500 meters in
depth when narwhals make a fall migration from north Greenland to their wintering grounds in Baffin
Bay (Laidre and Heide-Jørgensen). With success, scientists will have a better understanding of narwhal’s
winter habitats, along with rising water temperatures in the Arctic.
Narwhal whales have given rise to countless myths and legends over the ages. Existing in their
domain beneath the cold, deep waters, they have fascinated artists, philosophers, and storytellers.
Being one of the ocean’s most intriguing creatures, narwhals have evolved to take advantage of a world
dominated by ice. The Inuit’s hunting techniques and skills gave them access to the narwhal’s tusks,
which were subsequently traded to European explorers, who used the delicate spiral teeth to keep alive
the fable of the unicorn. Today, the narwhal is part of the Inuit diet in both Canada and Greenland,
where it is known respectively. In the early 21st century, researchers replaced the countless myths and
legends with biological descriptions and population survey data. In some cases, what we have learned is
reassuring, but in others the news is troubling. The narwhal’s habitat is changing, and the evidence is
growing that unless we do our part in protecting its fate, the narwhal could drift back into the realm of
legend.
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Range of narwhal sightings in Canada and Greenland. (Hrynyshyn)
[11]
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"Disease, the Scariest Threat." 2 December 2007. Canada.com. 18 November 2009 <http://www.canada.com/edmontonjournal/features/thebigthaw/features/thebigthaw/story.html?id=bae648e5-3533-49a0-9947-7f7f3a2d22d5&k=57488>.
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Hrynyshyn, James. "Canada's Narwhal Whale." (2004): 2.
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Laidre, Dr. Kristen and Dr. Mads Peter Heide-Jørgensen. "Tracking Narwhals in Greenland: Biology." 7 December 2007. NOAA Ocean Explorer. 18 November 2009 <http://oceanexplorer.noaa.gov/explorations/06arctic/background/biology/biology.html>.
Lambert, Katie. "Meet the Narwhal." 30 October 2008. How Stuff Works. 18 November 2009 <http://animals.howstuffworks.com/mammals/narwhal1.htm>.
"Narwhal." November 2009. Wikipedia, the Free Encyclopedia. 21 November 2009 <http://en.wikipedia.org/wiki/Narwhal>.
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