PHOTO: by Oceanwide Expeditions (see the website below)
September 12, 2007
TARONGA ZOO marine specialists are fighting to save the life of the second Antarctic leopard seal to be washed up on a Sydney beach in a week.
Found stranded yesterday morning at Clontarf, the gravely ill female had been badly mauled by a cookie-cutter shark. The zoo is already nursing a male leopard seal that was found on Tuesday last week on a beach at Wattamolla in the Royal National Park. It had also been attacked by a cookie-cutter shark.
Leopard seals were very rare in Sydney's waters, said Geoff Ross, a wildlife management officer with the National Parks and Wildlife Service. "We might see one every two or three years," he said, adding that finding two in a week was extraordinary. "They are Antarctic ice dwellers which seldom wander further north than Macquarie Island."
Mr Ross speculated the seals might have been washed towards Sydney by the Southern Ocean storms that helped drive Sydney's unusually heavy winter rain.
"But there is a not a lot of food for them to eat in the deep ocean," he said, noting they normally dined on sea birds, including penguins, squid and fish that they would haul out of the water and onto the Antarctic ice.
As a result of being so far from home, both seals were malnourished, exhausted and near death when found. The one rescued last week weighed just 90 kilograms, about 50 kilograms lighter than normal for its age.
Besides the leopard seals, five sub-Antarctic fur seals have also been found washed up on the NSW coast this year, adding to the puzzle.
Australian scientists reported last month that they had used satellites to track southern elephant seals swimming up to 2000 kilometres through Antarctic waters to find a meal, raising suggestions something has disrupted their normal Southern Ocean food supply, and forced them to hunt further afield.
Mr Ross said one possibility was that climate change had reduced the Antarctic food chain. "It's still a bit of a mystery," he said. "We can hypothesise about why the seals are here, but we really don't have good solid answers."
He estimated that 95 per cent of Antarctic seals swept onto NSW beaches died. Under an international agreement, those that are rescued and survive cannot be returned to the wild because there is a risk they might have picked up lethal viruses while exposed to humans and other land animals.
Mr Ross warned anyone finding stranded leopard and fur seals to keep clear. "They have a massive set of jaws, with teeth like serrated knives."
Taronga's spokesman, Mark Williams, said that while the female leopard seal was very ill the male found last week was improving and eating fish by itself.
PHOTO CREDIT: OCEANWIDE EXPEDITIONS