Australian Sea Lion
Encyclopedia
The Australian Sea Lion (Neophoca cinerea), also known as the Australian Sea-lion or Australian Sealion, is a species of sea lion
that breeds only on the south and west coasts of Australia
. It is monotypic in the genus Neophoca.
most closely related to other species of sea lion and fur seal
in the family Otariidae.
family. It is an 18 month cycle and is not synchronised between colonies. The duration of the breeding season
can range from 5 to 7 months and has been recorded for up to 9 months at Seal Bay on Kangaroo Island
.
Bulls do not have fixed territories during the breeding season. The males fight other males from a very young age to establish their individual positions in the male hierarchy and during the breeding season, dominant males will guard females for the right to breed with her when she comes into oestrus. A female comes into season for about 24 hours within 7 to 10 days after she has given birth to her new pup. She will only look after the new pup and generally fights off the previous season's pup if it attempts to continue to suckle from her.
Male Australian Sea Lions are also known to kill young as an act of defence of territory.
s colonised the continent.
Australian sea lions have very well-developed facial whiskers. Like all pinnipeds, such as seals and walruses, this useful homologous structure helps the sea lion to feel their way under the water and sense their prey. This is an inherited feature shared amongst all of the sea lion's close relatives.
Sea Lion
Sea lions are pinnipeds characterized by external ear-flaps, long fore-flippers, the ability to walk on all fours, and short thick hair. Together with the fur seal, they comprise the family Otariidae, or eared seals. There are six extant and one extinct species in five genera...
that breeds only on the south and west coasts of Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
. It is monotypic in the genus Neophoca.
Phylogeny
The Australian Sea Lion is a pinnipedPinniped
Pinnipeds or fin-footed mammals are a widely distributed and diverse group of semiaquatic marine mammals comprising the families Odobenidae , Otariidae , and Phocidae .-Overview: Pinnipeds are typically sleek-bodied and barrel-shaped...
most closely related to other species of sea lion and fur seal
Fur seal
Fur seals are any of nine species of pinnipeds in the Otariidae family. One species, the northern fur seal inhabits the North Pacific, while seven species in the Arctocephalus genus are found primarily in the Southern hemisphere...
in the family Otariidae.
Breeding behaviour
The breeding cycle of the Australian sea lion is unusual within the pinnipedPinniped
Pinnipeds or fin-footed mammals are a widely distributed and diverse group of semiaquatic marine mammals comprising the families Odobenidae , Otariidae , and Phocidae .-Overview: Pinnipeds are typically sleek-bodied and barrel-shaped...
family. It is an 18 month cycle and is not synchronised between colonies. The duration of the breeding season
Breeding season
The breeding season is the most suitable season, usually with favourable conditions and abundant food and water, for breeding among some wild animals and birds . Species with a breeding season have naturally evolved to have sexual intercourse during a certain time of year in order to achieve the...
can range from 5 to 7 months and has been recorded for up to 9 months at Seal Bay on Kangaroo Island
Kangaroo Island
Kangaroo Island is Australia's third-largest island after Tasmania and Melville Island. It is southwest of Adelaide at the entrance of Gulf St Vincent. Its closest point to the mainland is off Cape Jervis, on the tip of the Fleurieu Peninsula in the state of South Australia. The island is long...
.
Bulls do not have fixed territories during the breeding season. The males fight other males from a very young age to establish their individual positions in the male hierarchy and during the breeding season, dominant males will guard females for the right to breed with her when she comes into oestrus. A female comes into season for about 24 hours within 7 to 10 days after she has given birth to her new pup. She will only look after the new pup and generally fights off the previous season's pup if it attempts to continue to suckle from her.
Male Australian Sea Lions are also known to kill young as an act of defence of territory.
Population status and protection measures
There are approximately 14,730 Australian Sea Lions following the introduction of the Australian National Parks and Wildlife Act of 1972 which prohibited a harvest that began in earnest as soon as EuropeanEuropean ethnic groups
The ethnic groups in Europe are the various ethnic groups that reside in the nations of Europe. European ethnology is the field of anthropology focusing on Europe....
s colonised the continent.
Analogous and homologous structures
The Australian Sea Lion has many analogies with other species. For instance, sea lions use their flippers in a wing-like motion to propel themselves through the water. This is an analogous feature shared among many animals. Penguins, for example, are from a completely different class (birds) but also use a similar method of swimming underwater; their wings serve little point on land whereas in the water their wing structure acts similarly to flippers and allows them to dart around quickly underwater. Sea lions are similarly fast underwater and this helps them to catch their prey.Australian sea lions have very well-developed facial whiskers. Like all pinnipeds, such as seals and walruses, this useful homologous structure helps the sea lion to feel their way under the water and sense their prey. This is an inherited feature shared amongst all of the sea lion's close relatives.