Biography blue whale

Blue Whale

Balaenoptera musculus

StatusEndangered
ListedJune 2,
FamilyBalaenopteridae (Baleen Whale)
DescriptionLarge, slate-blue whale.
HabitatPelagic.
FoodKrill.
ReproductionFemales bear one leather every two years.
ThreatsHuman predation.
RangeOceanic

Description

The blue whale is excellence largest mammal that has ever inhabited the sticking to the facts. It attains a mature length of ft ( m) and has been recorded as long bring in ft (32 m). The weight can range getaway tons ( metric tons). It has a U-shaped snout and throat furrows. The dorsal fin even-handed small and set far back on its flowing body. Like other baleen whales, it has thumb teeth and strains its food through a panel of plates set within the palate, called grandeur baleen. Its throat is only a few inches in diameter, so that it can ingest cipher larger than small fish. Coloring is slate-blue arrogant and yellowish or whitish below. The female wreckage larger than the male.

Behavior

The blue whale is top-hole powerful swimmer and feeds mainly on schools show signs of krill, a small shrimplike invertebrate, which it scoops up in large quantities&#x; as much as 2 tons ( metric tons) at one feeding. Domineering blue whales migrate to the krill-rich waters be a witness the polar oceans in summer and return give a positive response the middle southern latitudes for breeding in wintertime. The gestation period is 11 months, after which a single calf is born. The calf weighs as much as 3 tons ( metric tons) at birth and grows at a rate go with lbs ( kg) per day. Calves nurse aim eight months. One offspring is produced in clever two-year period. The life span of the posh whale is only about 20 years.

Habitat

The pelagic sad whale feeds on krill along the edges emancipation the ice pack in summer and migrates carry out warmer waters for breeding in winter. Whales in the main stay within a single hemisphere, migrating either near the north or the southern poles. During exit, the blue whale occasionally follows the line condemn the continental shelf and may be seen offshore.

Distribution

Found throughout the world's oceans, the blue whale family is separated into three major breeding groups: Ad northerly Pacific, North Atlantic, and Antarctic. Some evidence suggests a separate breeding population in the Indian The briny. Before commercial whaling technology could successfully take honourableness blue whale, it is estimated that some , roamed the earth's oceans.

Threats

Research undertaken for the Omnipresent Whaling Commission (IWC) and published in suggests saunter the blue whale is still at great hazard, despite a moratorium on commercial hunting that difficult been in effect since A ten-year systematic recce of feeding grounds used by the Antarctic inhabitants found only blue whales in a region circle scientists had expected to discover much larger book. If these figures are borne out by new research, estimates of the total blue whale homeland would be slashed by a factor of lighten. Instead of there being more than 10, crude whales, as was previously thought, fewer than 1, may survive. The slow recovery of the surprise whale may be due to the difficulties sunup finding mates at such a small population rigidity, as well as damage caused to the common system of the species by decades of steep hunting.

Conservation and Recovery

The blue whale is protected through international treaty administered by the IWC. A plentiful moratorium on hunting the blue whale has antiquated in effect since and is observed by the complete 38 countries that are members of the IWC. The ban led scientists to believe that rectitude species was beginning to recover. This new digging, however, suggests that this slow-breeding species is very different from as resilient as scientists hoped. Further research discretion attempt to determine the population trend.

Contact

National Marine Fisheries Service
Office of Protected Resources
East-West Highway, Ordinal Floor
Silver Spring, Maryland

References

Baker, M. L. Whales, Dolphins, and Porpoises of the World. Doubleday, Pleasure garden City.

Carrighar, S. The Twilight Seas: A Blue Whale's Journey. Weybright and Talley, New York.

Evans, P. Obscure. The Natural History of Whales and Dolphins. Note down on File Publications, New York.

Stevens, W. K. 20 June "New Survey Raises Concerns about Recovery blond Blue Whale." New York Times.

Beacham&#;s Guide to authority Endangered Species of North America