Advertisements

White whale, Delphinapterus leucas (Reproduction, threat and conservation status) – Video

This video was taken at the Sea World, California, USA

Life history and reproduction

Males reach sexual maturity between four and seven years, while females mature at between six and nine years. The white whales can live more than 50 years.

Female belugas typically give birth to one calf every three years. Gestation lasts 12 to 14.5 months. Calves are born over an extended period of time that varies by location throughout the period from March and September. Newborns calves are uniformly dark grey in color and measures about 1.5 meters long, weigh about 80 kilograms.  The calves remain dependent on their mothers and nurse for about 2 years. As calves grow, the grey color lightens reaching their distinctive pure white color by the age of seven years for females and nine years for males.

It may worth mentioning that almost all white whales found in aquaria are caught in the wild, as captive breeding programs was not that successful.

Threat and conservation status

There are various threats that negatively affect white whale populations. The predation, hunting & human activities and pollution are the key threating factors.

Predation: Polar bears take particular advantage of situations when whales become trapped by ice and cannot reach the ocean. The orca is its other significant natural predator.

Pollution: Because the white whale is a long-lived animal, it is considered an excellent indicator species for environment health and changes. As the white whale congregates in river estuaries, pollution has proved to be a significant health danger.

Hunting and human activities: the data show that the white whale global population is much smaller compared to pre-hunting populations whether hunting was done by indigenous people or through previous commercial whaling.  Also, the disturbance caused by small boats, ships and whale-watching are threatening the whale populations.

Conservation status: As of 2008, the beluga is listed according to IUCN standards as “near threatened”. This classification has taken in consideration the uncertainty about the number of white whales over parts of its range, in addition to the possible qualification of whale population to “threatened” status if the conservation efforts cease, especially hunting management. The white whales are protected under the International Moratorium on Commercial Whaling. It may worth mentioning that sub-populations of while whale may have different conservation listing.

References: Natural history notebook, Wikipedia, Scientific papers

Advertisements

Permanent link to this article: http://fishconsult.org/?p=4997

%d bloggers like this: