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Australian Snubfin Dolphin
Australian snubfin dolphins are new dolphins.
They each have a small fin on the back.
They have a round head.
They don't make big jumps.
They live in water near the top of Australia.
Dolphins are part of the same family as whales. Snubfin dolphins are found only in Australian waters and are Australia’s only endemic, or native, dolphins. In 2005 scientists measured and tested dolphins they'd thought to be Irrawaddy dolphins and found they were actually a new species of dolphin, which they named the Australian snubfin dolphin.
Habitat and distribution
The Australian snubfin dolphin is found in the warmer waters near the northern coast of Australia, from Western Australia to Queensland, and in rivers and estuaries in water less than 15 metres deep. An estuary is where a river meets the sea .
Appearance
It gets its name from the small stubby dorsal fin on its back. It has a round melon-like head with a rounded forehead, and a crease of skin around its flexible neck. Only the Beluga whale has a neck like that, which enables it to turn its head. Unlike other dolphins found in Australia, the snubfin dolphin has no beak. There are a range of colours in the snubfin dolphin, from cream and shades of brown and grey. The underside is generally lighter in colour. The blowhole on the top of its head is not in the centre, but located a little to the left. The snubfin dolphin grows to between 1.5 and 2.7 metres long.
Behaviour
Australian snubfin dolphins are generally seen in groups of 5 or 6, but occasionally in groups of about 15. They are not acrobatic, but have been seen tail slapping and making small jumps. Their sounds include clicks and whistles. They generally make short dives and surface every minute or so, but can stay underwater for up to 12 minutes if they need to. They are quite shy, and don't swim around boats like other dolphin species do.
Diet
Australian snubfin dolphins eat mostly fish, but also feed on squid, octopus, prawns and crabs.
They catch their food in an unusual way: a group of dolphins form a circle with their heads above water, and they spit water, which makes the fish come to the surface where they are easily caught.
An Australian snubfin dolphin spitting water to attract fish to the surface
Life Cycle
Calves are born any time during the year, but most are born during winter months.
Like calves of others in the whale family, they are born tail first so that as soon as the head appears the calf can be guided to the surface to take its first breath. This is because dolphins and whales are not fish, they are mammals.
Conservation Status and Threats
The Australian snubfin dolphin is listed as ‘near threatened, data deficient’. This means that not much is known about the species, but what we do know indicates that it may be threatened. There may only be about one thousand of these dolphins in existence. Known threats to its survival include being caught in fishing nets; loss of their food because of overfishing by humans; water pollution and habitat destruction due to building and developments along the coast. Jet skis and boats cause injuries and disrupt their natural behaviour, and the noise affects them.
Actions that may help this species and other marine mammals:
Limit pollution by chemical waste from building sites. These poisons affect the mammals directly, or poisons the fish they eat and so affects them indirectly
Set fishing limits so that their food source is not killed off
Set limits for boats and other water craft so they keep their distance
Watch these videos of snubfin dolphins swimming, and learn more about the threats to their survival:
http://www.youtube.com/watch?v=eKOhDy_aAlE&NR=1
http://www.youtube.com/watch?v=8t2DeG1rpPo
Go here to find out more about Australian snubfin dolphins:
http://wwf.org.nz/media_centre/?4881/Rare-dolphins-threatened-by-boat-strikes-fishing-gear
http://www.marineparks.wa.gov.au/fun-facts/australina-snubfin-dolphin.html
updated September 2011 ©kidcyber