470 long-finned pilot whales were found stranded on the Australian coast of Tasmania last month in the country’s worst ever mass stranding, eclipsing the previous record of 320 in 1996.
An estimated 270 whales were found on a beach near the west coast of Strahan, Tasmania, on Monday 21st of September. Another 200, believed to be part of the same pod, were spotted the following day less than 10km south.
While rescuers managed to save over 100 of the stranded whales in a five-day rescue effort involving dozens of volunteers, the remaining 361 died. Jools Farrell, a rescue expert, described the complex process of returning the whales to the ocean. “The whole situation [needed] to be assessed,” explained Farrell, “We [needed] to take measures to keep [whales] hydrated, which is to keep [them] wet, to keep [them] from getting sunburnt, and we [needed] to make sure there [were] not large groups of people on the beach.” Rescue volunteers were equipped with kits including masks, gloves, tape measures and sheets, and rescue mats and slings were used to lift smaller whales back into the water.
Four whales were euthanised, with exhaustion precluding any viable chance of their release.
However, efforts were hampered by strong tides bringing freed whales back to shore. Vanessa Pirotta, marine scientist, also explained that the natural sociability of the species and gravitation towards the same pod meant that whales may have heard “the acoustics and vocalisation sounds that the others [were] making”, and that whales were likely “disorientated and in this case extremely stressed, and just probably so fatigued that in some cases they [didn’t] know where they [were]”. Four whales were euthanised, with exhaustion precluding any viable chance of their release. Kris Carlyon of the Marine Conservation Project explained that the decision to euthanise was made “purely on animal welfare grounds” and remained “the best, most humane course of action”.
A clean-up plan has now commenced, aiming to shift the hundreds of carcasses scattered along the coast. Nic Deka of the Tasmanian Parks and Wildlife Service warned of the possible risks posed should the carcasses wash back into the sea, including their potential to create navigation hazards, attract predators such as sharks, and even present a biological health issue through reducing oxygen levels and hence marine life whilst decomposing. “So the strategy is going to be collect and contain,” said Deka in a statement on Tuesday, “When conditions are suitable we will take them out to sea and release them”.
A dying matriarch attempting to beach herself may have led the entire pod towards the coast.
The causes of the stranding remain unclear. Pilot whales are prone to beaching in large groups due to their natural sociability; the species generally travels in large, tightly-structured communities reliant upon continuous communication. It is possible, therefore, that one individual - potentially a dying matriarch attempting to beach herself - may have led the entire pod towards the coast. Marine Conservation Program wildlife biologist Kris Carlyon emphasised the likelihood that this event was naturally-caused, stating that there was “nothing to indicate” any anthropogenic influence on the behaviour of the mammals. “We know strandings have occurred before,” affirmed Carlyon, “As far as being able to prevent this occurring, there’s little we can do”.
The team were “really, really pleased” with the number of whales saved.
Rescuers remained satisfied with their efforts, Carlyon expressing that the team were “really, really pleased” with the number of whales saved. “Each one you can help in any capacity, whether that’s to relieve their suffering or get out there and free them, is part of the job,” remarked marine ecologist Julie McInnes, who assisted with the rescue operation. “I think we all felt it might not be achievable at the start, so its been a really fabulous effort by everyone”. In total, 109 whales were freed, most of which are expected to make a full recovery.
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