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Fly Neighbourly Advice for the Tasman National Park

24/08/2019

Public comment is invited on the draft Tasman National Park Fly Neighbourly Advice. The draft Fly Neighbourly Advice has been prepared by the Tasmania Parks and Wildlife Service in response to increasing air traffic over the Tasman National Park.More

Hybrid diesel-electric shuttle buses at Cradle Mountain - a first for National p

19/08/2019

When you next visit Cradle Mountain you will be able to step aboard one of the new hybrid, diesel-electric, shuttle buses on your trip to Dove Lake. These new buses will reduce emissions and deliver a quieter, all mobility friendly, visitor experience.More

AFAC Independent Operational Review of the 2018-19 bushfires

08/08/2019

Following the 2018-19 bushfires the Tasmanian Government commissioned an independent report by the Australasian Fire and Emergency Service Council to review the overall response and identify areas where more can be done to improve the State's response andMore

Rissos Dolphin

Drawing by Graham Sanders
Risso’s Dolphins are robust dolphins with a blunt head, lacking a distinct beak. The forehead has a distinctive deep crease. The mouthline slopes upward and contain about seven pairs of teeth. The flippers are long, pointed and recurved and the dorsal fin is tall and sickle-shaped. Newborns are light grey and adults are a very light grey to white with a narrow cape on some individuals. The ventrum is dark with a large white anchor shaped grey patch. They often heavily scarred. Both sexes reach up to 230kg in weight. They are very gregarious swimming in groups of 25 up to several hundred and often swim in a line formation although single animals can be found swimming alone at times.

General Information

Risso’s Dolphins are abundant in tropical and temperate waters. They are still hunted off Japan. They generally occur in waters deeper than 1km . They are regularly seen with other cetaceans particularly pilot whales and they have been known to interbreed with Bottlenosed Dolphins. Calving is generally in summer although a newborn was recorded from Victoria in winter. Birth weight is around 60kg and 1.5m. Weaning occurs around 2m in length and maturity at about 3m length. They breed at two or three yearly intervals. They feed mainly on squid.

Stranding Information

Risso’s Dolphins have been recorded as stranding from all Australian States including one from Tasmania. All Australian records of strandings are single individuals although mass strandings have occurred in other parts of the world.