Sydney: A pod of 230 pilot whales was found stranded on the rugged west coast of Tasmania Wednesday, with Australian officials saying only half appeared to be alive.
Aerial images showed a devastating scene of dozens of black glossy mammals strewn across a long beach, stuck on the waterline where the frigid southern ocean meets the sand.
Locals covered survivors with blankets and doused them with buckets of water to keep them alive, as other whales nearby tried in vain to twitch free and yet more lay dead.
The whales were “stranded near Macquarie Harbour” said the state’s Department of Natural Resources and Environment.
“It appears about half of the animals are alive.”
Officials said marine conservation experts and staff with whale rescue gear were en route to the scene.
They will try to refloat animals that are strong enough to survive and likely tow the carcasses out to sea, to avoid attracting sharks to the area.
It is almost two years to the day since Macquarie Harbour was the scene of the country’s largest-ever mass stranding, involving almost 500 pilot whales.
More than 300 pilot whales died during that stranding, despite the efforts of dozens of volunteers who toiled for days in Tasmania’s freezing waters to free them.
Distress signals
The cause of mass strandings is still not fully understood.
Scientists have suggested they could be caused by pods going off track after feeding too close to shore.
Pilot whales - which can grow to more than six metres (20 feet) long - are highly sociable and can follow podmates who stray into danger.
That sometimes occurs when old, sick or injured animals swim ashore and other pod members follow, trying to respond to the trapped whale’s distress signals.
Others believe gently sloping beaches like those found in Tasmania confuse the whales’ sonar making them think they are in open waters.
The news came just hours after a dozen young male sperm whales were reported dead in a separate mass stranding on King Island - between Tasmania and the Australian mainland.
The young whales’ deaths may be a case of “misadventure”, wildlife biologist Kris Carlyon from the state government conservation agency told the local Mercury newspaper.
“The most common reason for stranding events is misadventure, they might have been foraging close to shore, there might have been food and possibly they were caught on a low tide,” Carlyon said.
“That’s the theory at the moment.”
In nearby New Zealand strandings are also common.
There, around 300 animals beach themselves annually, according to official figures and it is not unusual for groups of between 20 and 50 pilot whales to run aground.
But numbers can run into the hundreds when a “super pod” is involved - in 2017, there was a mass stranding of almost 700 pilot whales.
Notable whale strandings
New Zealand
New Zealand - considered one of the “hotspots” for whale strandings - has recorded incidents dating back to the 1800s.
The country’s largest reported mass stranding took place in 1918, when 1,000 whales beached on the remote Chatham Islands.
More recently, hundreds of pilot whales died after nearly 700 were found on the beaches of Farewell Spit - at the top of the country’s South Island - in February 2017. Another 145 died in a mass stranding the following year on Stewart Island.
Argentina
One of the largest known mass beachings in the last century was of false killer whales in October 1946, when an estimated 835 were stranded near Mar del Plata in Argentina.
Chile
In December 2015, more than 300 whales were discovered washed up in a remote Patagonian inlet in southern Chile. Scientists at the time called the sight of the stranding “apocalyptic”.
A surge in algae in the water, known as a “red tide”, was believed to be the culprit. It bloomed across the ocean around Chile in the early months of 2016, choking to death an estimated 40,000 tonnes of salmon in the Los Lagos region - or about 12 percent of the country’s annual production of the fish.
In July 2016, about 70 dead whales were also found on the southern Chile coast.
Madagascar
In May 2008, around a hundred whales swam onto the beaches of Madagascar, where three-quarters of them perished in the first mass beaching blamed on high-frequency sonar mapping systems deployed in the hunt for oil.
According to a report released by the International Whaling Commission in 2013, the culprit was a high-power 12-kilohertz multibeam echosounder system operated by an ExxonMobil vessel about 65 kilometres offshore. The company disagreed with the findings.
The use of anti-submarine sonars was also suspected of causing a mass beaching in 2002, when some 15 beaked whales perished in the Canaries after a NATO exercise.
Japan
In April 2015, around 150 melon-headed whales were discovered washed up on a stretch of beach in Japan.
The cetaceans, which usually live in deep water and are a member of the dolphin family, were thought to have either suffered from a parasitic infection that disrupted their ability to navigate, or had become unable to navigate in the sandy shoals.
Sri Lanka
In November 2020, Sri Lankan rescuers managed to save some 120 pilot whales in a gruelling overnight effort that involved the country’s navy.
Three pilot whales and one dolphin died of injuries following the mass beaching on the country’s western coast at Panadura some 25 kilometres south of the capital Colombo.
