Harbor Seals

by Samantha Ainsley

Harbor
Seals

Habitat

Along the coasts of the Atlantic and Pacific Oceans, the harbor seal can
be found. Harbor seals range from Alaska to Mexico on the coast of the Pacific
Ocean. And on the coast of the Atlantic, the shores of eastern Canada and
New England are home to many harbor seals. The harbor seal or Phoca vitulina,
meaning sea calf’ or “sea dog”, can also be found in Washington
State’s inland seas, mainly in Puget Sound and along the shores of the San
Juan Islands.

Description

Harbor seals have
oval-shaped bodies with a large back flipper, smaller side flippers, and
dog-like faces. Their spotted coats come in many different colors that range
from silver, bluegray, tan, to brown and black. Male harbor seals are slightly
larger than the females. While the average male can grow from five to six
feet in length, and weigh 200-300 pounds, the females grow to four and a
half to five feet in length and weigh 150-200 pounds. Most harbor seals
live to at least twenty-five years of age.

Giving Birth

Harbor seals in eastern Puget Sound and the shores of the San Juan Islands
give birth from mid June through August, and in southern Puget Sound from
July through September.

Pups

Seal pups weigh anywhere
between twelve and twenty pounds, and measure about two and a half feet
in length. Harbor Seal pups feed off of milk for the first three to six
weeks until they are weaned and able to care for themselves. Unlike most
seals, harbor seal pups can swim, but they will ride on their mother’s back
if they get tired. Mother seals are very protective of their young and will
hide or carry them to protect them.

Diet

Harbor seals rely on the
food source that is close to them. Depending on where they live, they are
known to eat sole, flounder, sculpin, hake, cod, herring, octopus, and squid.

Harbor Seal Behavior

Harbor seals spend their
time both on land and in the sea, about 50/50. They use their powerful back
flipper not only for swimming, but also for moving on land. To move on land,
harbor seals push with their back flippers and flop along on their bellies.

The average harbor seal can
dive to 1,500 feet (457 m) for up to forty minutes. However, most harbor
seals stay under water, on average, for about three to seven minutes in
a very shallow depth. Harbor seals can swim as fast as fifteen knots.

Harbor seals like to “haul
out” to bask in the sun and sleep. This takes place on beaches, spits,
bars, rocks, and log rafts. They also haul out to digest food, rest, nurse
their pups, or give birth.

While they are hauled out, harbor
seals often raise the head and hind flippers and lie in a “banana-like”
position. When they are resting in the water, harbor seals will lie in what
is known as the ‘bottling” position. In this position, they tilt their
head straight back and float on the surface (looking like a floating bottle).

The Harbor Seals of Puget
Sound

In 1997, there were
about 16,000 harbor seals living in Washington State. The population of
harbor seals in Puget Sound has been increasing since the 1970’s. Nearly
one half of the population lives in the waters off the San Juan Islands.

One of the reasons there has
been such a dramatic increase in the population is the Marine Mammal Protection
Act of 1972. This law protects harbor seals from bounties that were put
on the seals because it was believed that they were eating too much commercial
fish. It is now illegal to hunt, capture, kill, harass or in any way disturb
seals or any other marine mammal.

Many other reasons harbor
seals have been so successful in Puget Sound is the abundance of food (hake,
herring, etc.) and puping sites. However, due human disturbance, there is
a reduction of harbor seals in some areas.