Nature
PUBLISHED
Almost 100 whales have died on the beaches of a remote collection of islands in the Pacific Ocean following a mass stranding event. According to the New Zealand Department of Conservation (DOC), staff were notified of the stranding at midday on November 22 and attended at 3 pm, where they found 97 pilot whales and three dolphins stranded at Waitangi West Beach, Chatham Islands.
The rest of this article is behind a paywall. Please sign in or subscribe to access the full content.Twenty-six pilot whales were still alive, but had to be euthanized by staff due to their extreme weakness.
“Only 26 of the whales were still alive at this point, the majority of them appearing very weak, and were euthanised due to the rough sea conditions and almost certainty of there being great white sharks in the water, which are brought in by a stranding like this,” said DOC Biodiversity Ranger Jemma Welch in a statement.
According to the DOC, a serious power outage prevented communication and delayed the rangers from reaching the area until almost three hours after the alert was received.
The Chatham Islands is an archipelago of 10 islands around 800 kilometers (500 miles) off the coast of New Zealand that is home to around 600 residents. Attracted to the rich food sources that exist around the islands, many species of marine life make the Chatham Islands their home.
Despite very few sightings of whales and dolphins, the area is a stranding hot spot for pilot whales, alongside sperm whales, beaked whales, and various dolphin species. In 1918, the largest whale stranding in New Zealand history took place on these islands, with up to 1,000 individuals dying on the beach.
Whale strandings have increased in frequency over recent years, but researchers are still unable to pinpoint exactly why. This mass stranding follows Australia’s largest whale stranding on record back in September, where more than 450 whales beached in Tasmania.
One possible explanation is climate change driving food sources closer to the coast, where pods of whales can take a wrong turn or become trapped. Climate change-triggered events such as high waves may also trick whales' innate navigation system into thinking they are further from the shore than they are.
Other plausible explanations include extreme weather, increased predation by sharks and killer whales, and military sonar exercises driving whales into unfamiliar territory.
Whale strandings are not uncommon in New Zealand, with around 300 becoming stranded each year. While the exact cause remains unknown, an increase in strandings does not bode well for some of the more endangered whale species, and understanding how they occur is vital in conservation efforts of the future.
