Dozens of beached pilot whales have died after getting caught on a shallow sandbar off Tasmania’s west coast in the largest mass-stranding to hit the island in more than a decade.
Around 90 of the 270 animals that were spotted struggling in shallow water on Monday have since perished, rescuers announced on Tuesday.
A further 25 whales, which can weigh up to three tonnes, have been guided back out to sea, meaning that rescuers are now battling to save 155 that are fighting for their lives in shallow waters.
Kris Carlyon, a government marine biologist, said rescue operations will likely last several days, and ranked the job as ‘one of the trickiest’ he has been involved in.
Around 90 of the 270 pilot whales that were discovered beached up on a shallow sandbar off the west coast of Tasmania on Monday have since died, rescuers announced on Tuesday
Rescuers have managed to guide around 25 of the animals back into deeper waters, leaving around 155 of them battling for life in the shallow water, as teams work to free them
While Tasmania’s west coast is a hot-spot for whale strandings, Monday’s incident is the largest to have occurred for at least a decade on the Australian island
Sixty rescuers, including local fishermen and volunteers, are working in teams to help free the animals – using harnesses fitted to boats to guide them back out to sea
Environmental workers said a group of around 30 whales was found dead on a nearby beach on Monday, while 60 animals that were still stranded on the sandbar have since perished
Hampering rescue efforts are ‘ugly’ conditions including cold temperatures and rain, though Carlyon added that the conditions will help the whales survive longer by keeping them wet and cool.
Beached whales most often die of dehydration. The animals have a very thick layer of blubber that keeps them warm in deep-sea temperatures, but causes them to rapidly overheat near the surface.
A stranded whale may also be crushed to death by their own weight, without water acting as a support, or else if they are stranded in deep water they may drown if their blowholes are covered.
All of the whales have to be reached by boat, limiting the number that can be worked on at any one time, while rescuers are having to operate in teams to prevent hypothermia.
They are also battling the unusual tides in Macquarie Harbour, which are dictated by barometric pressure.
Carlyon said a team of around 60 rescuers – including local fishermen and volunteers – are being forced to ‘triage’ the whales, working to free those who are in the best condition and easiest to reach first.
Parks and Wildlife Service manager Nic Deka added that workers are using boats fitted with slings to drag the animals off the sandbar, along with teams of people in the water to guide the animal back into the ocean.
Scientists do not know how or why pods of whales become beached, but speculate that the group could have become disoriented after feeding near the sandbar, or else followed members of the pod who strayed off-course
Beached whales most-often died of dehydration as thick coats of blubber designed to keep them warm in the deep sea cause them overheat close to the surface – meaning cool temperatures in Tasmania should keep them alive longer
Rescuers are being slowed down because the whales can only be reached by boat, limiting the number of people who can help at any one time, and rescuers are having to operate in teams to prevent hypothermia
Rescue workers in thermal wetsuits to prevent hypothermia work to try and free a pilot whale stranded on a shallow sandbar near Macquaire Harbour in Tasmania
Though mass whale strandings occur relatively often in Tasmania, such a large group has not been seen in the area for more than a decade.
Scientists believe the animals – which were spotted from the air on Monday – come from two pods that number around 270 in total.
Most of a 30-strong group on a nearby beach were found dead Monday, while about 60 other whales on the sandbars are also believed to have since died.
Once the whales are returned to deeper water, Carlyon said, the biggest challenge will be herding the social creatures out of the sandbar-riddled harbour and back into the open ocean.
Scientists said it was unclear what caused the latest stranding, but Carlyon suggested the pod may have gone off track after feeding close to the shoreline or by following one or two whales that strayed.
Karen Stockin, an expert in marine mammals at New Zealand’s Massey University, said Tasmania was a ‘particular hotspot’ for pilot whale strandings in large pods.
Rescue workers say they are being forced to ‘triage’ the whales due to the large number, prioritising the healthiest and easiest-to-reach and rescuing them first before dealing with the trickier cases
Beached whales most often die of dehydration caused by overheating, but may also be crushed under their own bodyweight without water to support them, or else drown if water covers their blowhole
The stranded pod of pilot whales (pictured on Monday) spread across two sandbars and a beach off Tasmania’s west coast
Rescue workers are towed out to sea as they battle cold temperatures, rain, and unpredictable tides to try and save 155 pilot whales stranded off the coast of Tasmania
‘It seems to be a notorious whale trap… you do tend to get these mass stranding events there,’ she told AFP.
Stockin said that while pilot whales were typically more resilient than other whale species, rescuers faced a race against the clock as the mammals can overheat, their muscles deteriorate and their organs become crushed outside their natural environment.
‘Time is never your friend,’ she said. ‘So without doubt, the more expedited rescue missions are, the more likely there is an increased (chance) of survival.’
Mike Double, the head of the Tasmania-based Australian Marine Mammal Centre, said it was ‘tragic’ that such a ‘massive’ pod had become stranded but other whales had previously been saved from the same location.
‘The state team responsible for responding are extremely experienced and they’ll be absolutely working incredibly hard to get the best possible outcome,’ he said.