Australia: Investigation called after mass whale deaths

The Australian Greens party has called for the Federal Government to investigate whether a Navy operation triggered the mass stranding of 130 pilot whales off Tasmania.

A huge effort is now underway to bury the carcasses of the whales, which beached themselves in Marion Bay in the southern Australian state earlier this week.

Officials said the stranding was probably caused by the whales becoming disorientated in 'confusing coastal waters'. However, Tasmanian Greens senator Christine Milne has called for the country's defence minister Robert Hill to investigate the proximity of Navy sonar ships when the mass stranding happened.

'It's well known and quite well established that naval exercises using mid frequency or low frequency sonar do have a negative impact on whales, killing them in some cases, and also disrupting their ability to navigate,' Milne told Australia's ABC News.

The Australian Navy denied its vessels were in the area at the time of the strandings. It also said its mine hunters, which were taking part in an exercise off Tasmania, had now returned to Melbourne.

'From my understanding the whales would have been beached before the naval vessels were even in the vicinity of Marion Bay,' said Navy commander George Sydney.

Mark Pharaoh of the Tasmanian Parks and Wildlife Service, said it was unclear what happened, but believed complex topography of the area was probably to blame for the incident. He said the large bay has frequently changing water depths, sandy spits and rocky outcrops, as well as narrow opening to the ocean.

'It's a very common area for strandings,' said Pharaoh. 'The most common belief here is that, since these strandings are so regular, it's basically difficult country for a whale to navigate in.'

Wildlife officials and volunteers saved about 19 of the whales, but the 110 who died are being buried. Scientists have taken samples from the carcasses in an attempt to find out why the whales beached.

Source: www.divemagazine.co.uk