A dolphin that died after being stranded in Tasman Bay, Australia, September 24, 2020. -

Mell CHUN / AFP

After being stranded in a Tasmanian bay earlier this week, “pilot dolphins” who had survived had to be euthanized this Thursday by Australian rescuers.

On Sunday, the cetaceans were found washed up on sandbanks in a bay on the west coast of the island of Tasmania.

If the efforts of the rescuers made it possible to save 88 of them, the toll could however worsen further, the chances of survival diminishing over the hours.

“We still have a few animals that are still alive and which we believe are in a condition to be moved,” said Nic Deka, the manager of Tasmania Nature Parks.

"We have focused on those who seem to be the most viable"

He explained that the rescuers, whose task is "physically trying", will continue their rescue operations until nightfall as well as Friday.

"It is likely that we will continue our efforts to save them tomorrow ... We have focused on those who seem to be the most viable and with whom we are most likely to succeed," he said.

About 60 people, including environmental protection specialists and workers from nearby aquaculture farms, spent hours in the icy waters of Macquarie Harbor, amid the cries of dying cetaceans.

“There are animals swimming around, they make sounds.

We see the links they have between them and those who form a couple ”.

The "pilot dolphins", which can be up to six meters in length and weigh a ton, are known to be particularly outgoing.

Some of them resisted the means deployed to save them and tried to return to their families after being released, which led them to run aground a second time.

The level of distress of some pilot whales is such that the authorities said they had been forced to proceed with the slaughter of at least four "pilot dolphins" to shorten their suffering.

"We have a few more that we are currently looking at on a veterinary basis," said Kris Carlyon, marine biologist in the Tasmanian Department of the Environment.

Rescuers on Thursday focused their efforts on 20 to 25 cetaceans, partly submerged, using boats with cables attached to escort them out to sea.

Stranding, an unexplained phenomenon

But now, they are forced to think about the best way to evacuate the carcasses of the nearly 400 mammals that have already perished.

"We are starting to develop a plan, we are prioritizing their disposal at sea. We continue to seek expert advice on exactly where they should be left," said Nic Deka.

Once abandoned, the carcasses will “swell and float” which can pose a danger to navigation, pollute the bay and attract sharks and other predators.

"The decay of so many animals could affect oxygen levels in parts of the bay and disrupt marine life there," said Nic Deka.

The reasons why cetaceans sometimes fail in droves like this remain unknown even to scientists who have studied this phenomenon for decades.

Some researchers believe that these pilot whales could have deviated from their route, attracted by food located near the shore, or that they would have followed one or two of them who would have strayed.

For Kris Carlyon, this is a "natural event", strandings of the species having occurred regularly throughout history, both in southern Australia and New Zealand, as well as than in other parts of the world.

"We intervene in this kind of situation but there is not much we can do to prevent this from happening again," he stressed.

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