The Australian 1 Aug 08;
A DIMINUTIVE dolphin called "Snubby" may make history in marine science if DNA samples taken this week from animals off the northwest Kimberley coast prove they are the world's newest dolphin species or sub-species.
The Australian snubfin dolphin, whose short dorsal fin and rounded snout differs radically from those in other dolphin species, was discovered in 2005 insmall populations across the Top End and north Queensland coasts.
The shy species was initially mistaken for an Irrawaddy dolphin, which is found in coastal areas and rivers in Southeast Asia. However, it was later confirmed as a new species unique to Australia, and the first new dolphin species found in the world for 50 years.
But the "snubbies" swimming a few hundred metres offshore from Broome's popular tourist beaches may reveal even more diversity if they are found to be a unique sub-species restricted to the Kimberley region.
Scientists from WWF Australia, led by cetacean ecologist Deborah Thiele, spent this week collecting dolphin skin samples using darts launched from a boat, to confirm whether Kimberley snubfins differ from the other northern Australian populations.
She said their long isolation from animals living further north and east along Australia's coastline could have caused evolutionary differences.
"There's been no genetic information from the Kimberley so they may be a separate species again," Dr Thiele said.
"We're doing work here and in the Northern Territory to clarify whether the dolphins we're seeing are an Australian snubfin or another new species."
Such a finding would be welcome news at a time when dolphin species are declining worldwide.
The Chinese Baiji dolphin, once found in the Yangtze River, has been declared extinct after an extensive scientific search in 2006 failed to turn up a single animal.
Dr Thiele said the Broome expedition, while yielding the possibility of a new scientific find, had also turned up good numbers of dolphins. The team recorded the first footage of snubfin dolphins spitting into the water, a technique used to herd and capture fish prey.
"But if the populations are very isolated, it means they need even more protection because there's not a huge gene pool," she said.
Tammie Matson, WWF's spokesperson for species conservation, said coastal and river dolphins were among the world's most endangered mammals.
