Common Name: Pygmy and Dwarf Sperm Whales
Class:
Mammalia
Order:
Cetacea
Family:
Physeteridae
Genus:
Kogia
Species: Two
species:
Pygmy Sperm
Whale Kogia breviceps
Dwarf
Sperm Whale Kogia simus |
Taxonomy/Description
Pygmy and dwarf sperm
whales belong to the Mammalian Order Cetacea, in the suborder
Odontoceti. All toothed whales belong to the suborder Odontoceti,
which is Latin for "toothed whales". They both belong to the sperm
whale family, Physeteridae. The other members of this family are
the sperm whale and the dwarf sperm whale. The pygmy sperm whale's
scientific name is Kogia breviceps. Some researchers place
pygmy and dwarf sperm whales in a separate family, Kogiidae. The
generic name, Kogia, is possibly Cogia Effendi, a Turkish
naturalist and whale researcher. The pygmy sperm whale's specific
name, breviceps, is derived from the Latin brevi,
meaning "short", and caput, meaning "head". The dwarf sperm
whale's specific name, simus, is Latin for "flat-nosed".
Pygmy sperm whales reach
8-11ft in length and about 700-890lbs in weight. Dwarf sperm whales
reach 6-8ft in length and 300-600lbs in weight. Both species have a
spermaceti organ, like the sperm whale, Physeter macrocephalus,
but differ in a variety of ways from their much larger cousin. The
blowholes of pygmy and sperm whales are located on the forehead of
the animals, not on the tip of the snout. A curved ridge is present
on both species, located on each side of the head behind the edge of
the mouth.
Habitat/Diet
Both species inhabit
tropical and temperate waters worldwide. Remains of deep sea
crustaceans were found in the stomachs of stranded individuals,
although the primary component of the pygmy and dwarf sperm whale
diet is squid.
Behavior/Reproduction
Small groups of 3-5 are
common for both species. The gestation period fro the pygmy sperm
whale is about 11 months. Pygmy sperm whale calves are about three
feet in length at birth. Very little is known about the social
structure of either species.
Conservation
Pygmy and dwarf sperm
whales are rare. Population estimates do not exist. Neither
species is considered endangered. Attempts to individuals alive in
captivity have failed.