The climate crisis means reduced levels of sea ice and the shorter time left to cover the Arctic Ocean are combining to open up larger areas of open water for killer whales, new research reveals.
But scientists have warned that the growing presence of these intelligent predators could potentially create an ecological imbalance that damages habitats and the species that live there.
In recent years, scientists have increasingly followed killer whales moving through the Arctic, where animals are able to team up to hunt larger prey like seals, walruses and even other whale species.
A University of Washington research team that has studied animals using acoustic tools to find and track them, used eight years of data to reveal how the species is spending more time than ever before in the ‘Arctic ocean.
Scientists said this behavior can also put whales at risk, as rapid temperature drops can freeze the sea, putting them at risk of ice entrapment.
The team said the change in whale behavior comes “directly as a result of the decrease in sea ice in the region.”
Brynn Kimber, of the University of Washington, who led the research, said: “It’s not necessarily that killer whales have never been seen in these areas before, but that they appear to stay in the area for. longer periods.
“This is probably due to a longer open water season. “
She noted that although there remains a high degree of variability, the minimum sea ice in the Arctic during September is declining at an average rate of 13% per decade, compared to values from 1981 to 2010.
“Killer whales are seen in the Chukchi Sea (in the Arctic Ocean) in months that were historically ice-covered and more regularly throughout the summer,” she added.
The team said the reduction in sea ice may have opened up new hunting opportunities for killer whales if certain prey species are unable to use the ice to avoid the highly adaptive predator.
They suggested that the endangered bowhead whale may be particularly vulnerable to predation by killer whales, with the risk to this species likely to increase due to longer open water seasons.
The research is presented to the Acoustical Society of America.