Why Were so Many Pilot Whales Stranded Last Year and Will it Continue?

After a mass beach stranding in July 2023, scientists are keeping a watchful eye on the pilot whale's mysterious behavior.

By Donna Sarkar
Jun 28, 2024 7:00 PM
Pilot whale strandings and attempted rescue
(Credit: Neil Bradfield/Shutterstock)

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Pilot whales have always been joined at the hip. In fact, the tendency for a group of pilot whales to follow the direction of a group leader is exactly what earned them their name. Now, these nomadic oceanic dolphins are finding themselves navigating into shallow waters, leaving them stranded on various beaches in masses.

A Sudden Increase in Pilot Whale Stranding

Although stranding of pilot whales has been occurring for millions of years, there has been an alarming increase of global mass strandings since 2023.

In July 2023, nearly 97 pilot whales were found beached on Cheynes Beach in Albany, Australia. Given Australia’s history of pilot whale strandings, this was not uncommon. Regardless, the mass stranding repeated itself shortly after on the Isle of Lewis in Scotland in the same month, killing yet another 55 pilot whales. The incident once again repeated itself in November with nearly 34 pilot whales washing up on Byrans Beach near the east coast of Tasmania.

All the pilot whales stranded in Western Australia as well as Scotland last year passed away.

“Unfortunately, the outcome for our pilot whales once they strand on the beach is generally not good,” says Pia Courtis, a regional wildlife officer with the Western Australia Parks and Wildlife Service, according to Inside Edition.

Nearly 150 pilot whales were found stranded just in April 2024 in Toby Inlet near Dunsborough, Australia. Luckily, rescuers responded rather quickly, returning nearly 130 of them back to deep waters.


Read More: How to Respond to Stranded Marine Life


What Is Whale Stranding?

Whale stranding, also referred to as beaching, occurs when dolphins and whales strand themselves on beaches, often resulting in the animal’s death. Strandings can occur for these species alone or in masses, though it’s been unusually frequent for the pilot whale species recently. Because both short and long-tailed pilot whale species typically prefer deeper waters, their recent mysterious beach stranding behavior has alarmed scientists.

There are many theories on why this suicidal behavior occurs. Looking into a few common reasons for stranding may help us understand this strange phenomenon better. Whales or dolphins can strand due to:

  • Bad weather: Rough or dirty waters can make it especially tough to navigate clearly, causing stranding.

  • Navigation errors: Trouble can occur when a mass of pilot whales follow the navigation of a disoriented whale, leading the entire group to strand.

  • Sickness: It’s not unusual for a sick or old and disoriented whale or dolphin to find themselves in shallow waters alone.

  • Birthing: Matriarchs of the pilot whale group have been known to pilot the whales into shallow waters especially while giving birth.

While it is possible for a whale to survive stranding, it’s unfortunately not typical due to overheating and their sheer body weight, which causes their organs to collapse on land. Of course, this is dependent on how long the rescue takes and if the animal is healthy enough to release back into the ocean. Other times, euthanasia may be the most viable alternative to avoid a painful death.


Read More: How Many Whales Are Left In the World?


Causes Behind the Mass Strandings

With repeated group strandings of pilot whales occurring globally, scientists are questioning what could be leading to these recent occurrences.

Environmental factors such as sloping sandy beaches have been causing whales to confuse the water’s depth and their surroundings. Humans may also be to blame for the recent mass strandings.

According to a recent study published in the British Ecological Society, oceanic animals can be greatly perturbed by noise pollution. This noise is often caused by seismic guns utilized for oil and gas exploration at sea and can drive the pilot whales away. Long-term climate change, which can lead to a loss of habitat for many oceanic creatures, has also been predicted to contribute to mass whale strandings, according to a study published on ScienceDirect.

If human activities like noise pollution at sea and whale hunting as well as environmental issues such as the deterioration of beaches and long-term climate change continue to persist, then it is also likely for mass pilot whale strandings to keep occurring.


Read More: Human Noise Is Flooding the Seas' Natural Soundscape


Article Sources

Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:


Donna Sarkar has a bachelor's degree in Journalism and Psychology from Marquette University. Her collection of work features deep dives into human psychology as well as the latest health and technology news. Her work has also been published in a variety of newspapers and magazines, including wikiHow, All That's Interesting, Health Digest, and Milwaukee Journal Sentinel.

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