Paws of polar bears sustaining ice-related injuries in a warming Arctic

by Hannah Hickey, University of Washington
October 22, 2024

Polar bears in some parts of the high Arctic are developing ice buildup and related injuries to their feet, apparently due to changing sea ice conditions in a warming Arctic. While surveying the health of two polar bear populations, researchers found lacerations, hair loss, ice buildup and skin ulcerations primarily affecting the feet of adult bears as well as other parts of the body. Two bears had ice blocks up to 1 foot (30 centimeters) in diameter stuck to their foot pads, which caused deep, bleeding cuts and made it difficult for them to walk.

The study led by the University of Washington was published Oct. 22 in the journal Ecology. It’s the first time that such injuries have been documented in polar bears.

The researchers suggest several mechanisms for how the shift from a climate that used to remain well below freezing to one with freeze–thaw cycles could be causing ice buildup and injuries.

“In addition to the anticipated responses to climate change for polar bears, there are going to be other, unexpected responses,” said lead author Kristin Laidre, a senior principal scientist at the UW Applied Physics Laboratory and a professor in the UW School of Aquatic and Fishery sciences. “As strange as it sounds, with climate warming there are more frequent freeze-thaw cycles with more wet snow, and this leads to ice buildup on polar bears’ paws.”

Keep reading: https://www.washington.edu/news/2024/10/22/paws-of-polar-bears-sustaining-ice-related-injuries-in-a-warming-arctic/

Read the Ecology paper: https://esajournals.onlinelibrary.wiley.com/doi/full/10.1002/ecy.4435