Australia's southern island of Tasmania, which sees more mass whale strandings than anywhere else in the world, has developed the first technique to successfully rescue giant sperm whales.

The method, in which nets are positioned under the whales with the help of jet-propulsion powerboats, was used recently for the first time to free seven whales from a sandbar at Strahan on Tasmania's rugged west coast.

Jet-propulsion powerboats are used to dig holes around the semi-submerged animals and the nets are then used to pull the whales into the holes and into increased flotation. The boats used are 350 horsepower, achieve very shallow draft, have no propellers and therefore have very little risk of injuring the animal. Before this technique, little could be done to save stranded sperm whales.

Around 30 whales are reported stranded in Tasmania each year. At an average of one every 12 days, this is more than the other two hotspots, New Zealand and the North Sea. Accounting for 80 percent of whale mass strandings in Australia, Tasmania has been reporting sharply increasing numbers of strandings since the early 1980s. Tasmania's northwest coast is very tidal, which can take an animal from safe deep water to a stranding in a matter of hours. For some species with strong social bonds, when one strands, the rest follow.