Common Name:
Humpback Whale
Class: Mammalia
Order: Cetacea
Family: Balaenopteridae
Genus:
Megaptera
Species: Megaptera novaeangliae |
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Taxonomy/Description
Humpback whales belong
to the Mammalian Order Cetacea, in the suborder Mysticeti. All
baleen whales belong to the suborder Mysticeti, which is Latin for
"mustached whales". The humpback whale belongs to the rorqual
family, Balaenopteridae. The word "rorqual" means "tube whale or
furrowed whale", referring to the pleats on the lower jaws of
rorquals. All rorquals have baleen, a dorsal fin and throat
grooves. Other members of this family include the blue whale, fin
whale, and minke whale. The humpback whale's scientific name is
Megaptera novaeangliae. Its generic name, Megaptera,
means "large fins", which refers to the humpback whale's extremely
long pectoral fins. These fins are extremely long, growing as long
as one third of the whale's entire body length. The humpback
whale's specific name, novaeanglinae, means "New England".
The first specimen of this species was identified off the coast of
New England. The common name "humpback" refers to the whale's odd
posture. Its body is angled, with its head and flukes pointed
downward. The back arches upward, giving a humped appearance.
Humpbacks grow to lengths of 40-50ft and weights of 25-40 tons.
Females are slightly larger than males. This species is easily
recognized by its very large, white pectoral fins. The fins are
very knobby on the posterior side.

Habitat/Diet
Humpback whales are
found in all oceans. Their major food sources are krill and small
fish. Quantities of food greater than one ton are consumed each
day. As the whale opens its large mouth to gulp up its prey, the
pleats of its lower jaw expand to contain the large volume of
water. The whale then presses it tongue up against the roof of its
mouth, straining the water through its 250-400 baleen plates. These
30 inch plates are composed of keratin, the same substance of
fingernails and hair. The ends of baleen are brush-like, preventing
the fish or krill from escaping. The prey remains inside, and are
consequently swallowed.

Reproduction/Behavior
Humpback whales engage
in a variety of acrobat behaviors. Fluke slaps, fin slaps, and
breaching are all characteristic of humpback whales. These aerial
shows are quite genuine, because it is rare for large animal species
to engage in such behaviors. Some researchers believe these
displays are a type of communication between whales.
Most scientists agree
that humpback "singing" is a communicative behavior. This species
of whale is famous for its 10-20 minute vocal displays, which travel
miles away from the singer. Humpback songs differ between regions.
The songs change slightly within the population from year to year.
Since solitary males perform the songs, scientists infer this
behavior advertises availability to receptive females.

Humpbacks migrate
annually. Summers are spent feeding in cooler temperate and arctic
waters. Winters are spent calving and breeding in tropical waters.
Bulls compete by thrashing their tails and pushing one another to
get closer to a receptive female. After a 12 month gestation, a
10-15ft long, one ton calf is born. It nurses for about one year,
but will remain with its mother for longer.
A very interesting
humpback behavior is called "bubble netting". This is characterized
by a hunting group of humpbacks releasing streams of bubbles from
their blowholes while underwater. The bubbles confuse schooling
fish, which react by clumping close together. The bubbles scare the
school towards the water surface. The fish are trapped at the
surface and the humpback pod attacks the fish from below.

Conservation
Humpbacks were hunted
by whalers once the larger species of whales became depleted. As
slow swimming, shallow water animals, humpbacks were very easy
targets. The International Whaling Commission banned humpback
hunting in 1966. They are protected under the United States' Marine
Mammal Protection Act of 1972 and the Endangered Species Act of
1973. The humpback population is currently recovering, and is
estimated between 30,000 and 40,000 individuals.
