Why Mass Whale Strandings Are A Big Deal For The Oceans
470 whales recently became stranded in Tasmania, in the worst case of whale-stranding Australia has even seen. And because whales are so integral to the ocean’s ecosystem, this stranding could have really significant consequences.
What Does A Whale Stranding Of This Scale Mean For The Environment And Why Do They keep On Happening?
270 pilot whales beached themselves on a sandbank at Macquire Heads on Tasmania’s West Coast. Just two days later another 200 whales had been stranded, all part of the same pod and all stuck in shallow waters.
Rescuers have been trying to get the whales back into deep waters. They’ve managed to save 50 so far, but already 380 have died.
The situation in Tasmania is significant because whales are really integral to the ocean’s ecosystem. They keep the food chain in order and even help offset the amount of carbon in the earth’s atmosphere.
Even after they die, whale carcasses tend to sink to the seafloor and become a huge source of nutrients for other species to feed off.
Whales are also a huge part of Australia’s tourism industry, especially in coastal regions where whale-watching tours bring in millions of dollars.
This isn’t the first time mass whale strandings have occurred in Australia. They’re actually quite common and there have been similar incidents around the world. The worst was back in 1918 when 1,000 pilot whales became stranded on New Zealand’s Chatham Islands.
But what’s unfolding this week is set to become the worst whale stranding in Australia’s history, with Tasmania now even being referred to as a global hotspot. But even though whale strandings have happened before, scientists are still finding it extremely hard to actually pinpoint why.
Dr. Vanessa Pirotta: “If I knew then it would be so helpful to predict when these things were going to happen, but we just don’t.”
That’s wildlife scientist Dr. Vanessa Pirotta.
VP: “Misadventure could potentially be one key component. As well as that, these animals may have been startled and scared, and as a result they’ve just darted in one direction – which is the wrong direction.
Unfortunately, it’s mis-navigation. So, there was an error in a couple of individuals that have led the entire pod into this area which has resulted in absolute tragedy.”
Dr. Pirotta told me that whales are extremely social animals (kind of like each other’s ride or dies) and usually, when a singular whale becomes beached it’s because they’re old, sick or injured.
She explained that when we see these large numbers of whales undertaking mass behaviour that leads to them being stranded, chances are they are vocally responding to one another.
VP: “They will stay in these strong bonds for the rest of the lives, so when one goes one direction then the others are likely to follow.”
So, one scientific train of thought is that this whole tragedy could very well be the result of one bad decision made by a leader whale.
But in a year, that’s dealt us deadly bushfires and a global pandemic, it’s hard to overlook the role humans play when natural disasters hit.
VP: “Us as humans need to be aware that we produce a lot of human sounds in the ocean, also known as anthropogenic sound. This means that the more sound we create through sources like shipping, underwater construction, and vessel activities, will all reduce the available space that animals have to talk to each other – and it can become really noisy.”
Dr. Pirotta did tell me that pilot whales aren’t endangered and that the deceased whales will actually be helpful for future research, to figure out how to stop this from happening again.
But for now, experts are losing time to save the whales that still need help in Tasmania, and really the whole situation is a huge wakeup call for how we could be better protecting the largest mammals on earth.