UNICORN OF THE SEA
KELLY WOLLMAN 2012
Long sought for its ivory tusk—once believed to be the horn of the fabled
unicorn--the narwhal is a mysterious creature. Its arctic habitat and atypical
migrations make It a species that remains difficult to understand and study.
Learn about the population distribution, their unusual tusks as well as information
detailing their diet and growth process.
size of a narwhal compared to a school bus
AN ARCTIC LIFE •known narwhal population range
Narwhals live in the Arctic Ocean year-round, rarely crossing the 70°N latitude
line, They migrate from coastal areas to off shore locations during seasonal
FOOD TO DIVE FOR
Narwhals participate in oceanic dives to
forage for food. As a migratory creature a
narwhal’s diving depths vary greatly from
summer to winter.
In the summer, narwhals make brief, shallow dives
between 100 and 1000 feet.
Narwhals begin their migration in the fall. During
this time, their average dive depths increase as well
as their dive durations. They travel fast, so there is
not much focused diving that occurs.
Winter months mean deep diving for narwhals.
They stay In a fairly limited area and move through
cracks in shifting pack ice. During this season,
narwhals make some of the deepest dives ever
recorded for marine mammals, hunting at depths of
almost 5,000 ft where water pressure becomes
extreme and light cannot reach.
Seasonal depth variation may occur with differences in locations of the narwhals represented.
NARWHAL SEASONAL DIVE DEPTH (ft)
-average diving range
ON A SUMMER DIET The typical narwhal diet changes seasonally
Recorded stomach contents imply that
they feed much less during the summer
months, but when they do eat, they feed
mostly on polar and Arctic cod.
In the winter, their diet is dominated by
Greenland halibut and Gonatus squid
Few types of prey other than the ones listed
above have been found in the narwhal stomach
which suggests an extremely specialized diet.
Size of circle indicates amount digested
DEFINING TRAIT: THE “HORN”
The narwhal tusk is actually a tooth that grows in a spiral
shape through the upper lip of a male. This tooth can
reach lengths of 7- 10 feet long.
Females may grow a tusk as wet but it does not
become as prominent as the male’s.
The purpose of the ivory tooth has boggled scientists for
centuries and is still unknown. Theories include its
importance during mating rituals, usefulness while
foraging or as a sensory organ to feel out Its
Due to its similarities to a
unicorn horn, the narwhal
tusk has historically been
hunted for the tusk’s believed
Centuries ago, the narwhal
tooth was sold as a unicorn
horn for ten times its weight
DEFINING TRAIT: IT’S A FLUKE
The variation between the male and
female flukes is directly related to
swimming performance. The male’s fluke
helps account for drag caused by their
tooth, while the female’s fluke provides
speed for diving.
The size and weight of the male’s tusk (as
long as 9 feet and weighing as much as
22 pounds) has changed the shape of the
narwhals flukes over time.
MALE FLUKES FEMALE FLUKES
Male flukes have a slight concavity towards
the outer edges, while females are shaped
more like those of dolphins.
Maturity is typically reached around nine years, but narwhals continue to change color as they age. A calf is darkest at birth and develops a mottled greyish and white pattern with age.
5 ft 30 ft
200 lbs 3,500 lbs
NEWBORN 10 YEARS 50 YEARS
GROWING PAINS AVERAGE MALE NARWHAL
THREATENED SPECIES STATUS
least concern -- near threatened -- vulnerable -- endangered -- critically endangered -- extinct in the wild --- extinct
As of 2008, with an estimated population in excess of 80,000 members, the narwhal
is listed as near threatened on the IUCN red list of threatened species.