A new study from the University of Washington reveals that Arctic sea ice loss impacts the migration of some beluga whales, while the migration of others remains the same.
Researchers studied two distinct beluga whale populations in the Arctic. The both spend winters in the Bering Sea and swim north in the early summer as ice melts and they gain access to the Beaufort and Chukchi seas. Both populations feed in the summer and migrate back to the Bering Sea in the fall.
As Arctic sea ice takes longer to freeze up each fall (thanks to climate change), the Chukchi population delays its annual southward migration by up to a month. However, the Beaufort population hasn’t altered its migration pattern.
This suggests that the Chukchi population is feeding later into the fall, which could be good or bad. It’s good because the whales have more food, but it could be bad if the ice unexpectedly freezes up and closes the whales in.
“The biggest take-home message is that belugas can respond relatively quickly to their changing environment, yet we can’t expect a uniform response across all beluga populations,” said lead author Donna Hauser, a postdoctoral researcher at the UW’s Polar Science Center.
Hauser explains that the Beaufort population’s “apparent indifference to sea ice timing” is surprising, given that the two populations have such similar life histories.
“If we’re trying to understand how these species are going to respond to climate change, we should expect to see variability in the response across populations and across time,” Hauser said. “That may complicate our predictions for the future.”
To learn more:
- Read the UW news release: Arctic sea ice loss impacts beluga whale migration
- Read the full study: Decadal shifts in autumn migration timing by Pacific Arctic beluga whales are related to delayed annual sea ice formation
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