Short description of some of the whales that can
be seen around San Diego are given below. By far the most common
is the California Gray Whale seen
during it annual migration down the west coast from Alaska to Baja,
Mexico. Much of the following is taken from the American Cetacean
Society.
California Gray Whales
The Gray Whales can reach a length
of 52ft,
a weight of 36 tons and an age
of 60 years. The California
Gray Whale for as large as they seem to us, is really just a mid
size whale. They get their name both from the gray slate color
of their skin as well as from the gray-white patterns left by parasites.
The
California Gray Whale is classified as a baleen
whale because it filters its food out from large quantities
of sea water.
It feeds on small crustaceans from the ocean bottom that it dislodges
by rolling on it side. It them swallows the surroundsing
water and filters the nutrients out.
The gray whale has no dorsel (top)
fin, but does have a dorsal hump about 2/3 of the way back on
its body
followed by a series of 6-12 knuckles along the dorsal ridge
that extend to the flukes
Gray whales reach sexual maturity sometime
after 5 years of age. Their gustation period is around 12 months
and after birth calves nurse 7-8 months on milk that is 53%
fat (human milk is 2% fat). One calf is born per mother
every couple years.
Breathing patterns are generally
blowing 3-5 times in 15-30 second intervals before raising its fluke and
submerging for 3-5 minutes. A gray whale can stay submerged up
to 15 minutes.
Blue Whales
The Blue Whales are probably the largest
animal to have ever lived on the planet - they are 70 to
100 feet in length, can weigh over 100 tons and have a
distinctly
blue color. They are also very fast swimmers and can swim at 30
knots if they choose.
It is strange that the largest animal
on the planet eat almost exclusively small, shrimp-like creatures
called krill - about 4 tons of them each
day when feeding. Since these whale are baleen whales they
filter the krill out from massive amounts of water.
They reach sexual maturity at a similar
age to the gray whales and have a slightly shorter gestation period.
During nursing (a period of about 7 months) the calf consumes 100
gallons of milk a day and gains about 200lbs/day in
weight.
Today there are about 15,000 blue whales
which is less than 5% of their pre-whaling population. They are
found in all oceans of the world.
Orca (Killer Whales - Shamou)
Most people are familiar with Orca (Killer
Whales) becausee of Sea Worlds's Shamou. They are about 30 feet
in lenght and have a very distinctive dorsel
fin which is several
feet tall. They have teeth and feed on a variety of animals such
as fish, porpoises and seals.
Orcas do migrate, but not on fixed
routes and tend instead to follow food supplies. They have no natural
enemies but are having health issues because of chemicals in the
other animals which they consume. Their populations are worldwide.
Orcas seem to have no fixed breeding season
as calfs are observed throught the year. They reach maturity much
later than other whale species, nont until 10 to 18 years of age.
Interestingly the sounds of each Orca
pod are unique.
Finback Whale
They are second to the gray whale in size
measuring in at around 80 feet with
a
weight of aroudn 60 tons. They are long and sleek and like
the gray whale are fast swimmers. Being also a baleen
whale they coral fish in tight circles before engulfing them.
The reproductive data is about the
same as the other whales but they only breed each 3 - 4 years.
They are found in all oceans of the world and migrate. Their
populations is about 40,000 - a small percentage
of their origional population.
Humpback
Whale
Humpbacks whales measure
around 45ft in length and weigh about 40 tons.
They are more rotund and not as sleek as some of the
other whales mentioned. The upper part of their body is black with
the underside being white or mottled.
They are know best for 2 traits. First
they are very acrobatic and exhibit behaviors like breaching or
swimming on their back. The second trait is that of their song.
The males sing songs that last for approximately 15 minutes that
may repeat for hours at a time.
They feed on krill or small fish and filter
it using baleen - eating up to 1.5 tons of food each year. These
whales are found in all the worlds oceans. Their populatios is
around 35,000 - about 1/3 of their origional population