Arctic Polar Bears Face New Threat From Emerging Pathogens

Polar bears in the Arctic’s Chukchi Sea face increasing risks from pathogens they were previously unexposed to, according to new research from the U.S. Geological Survey’s Alaska Science Center.

Published in PLOS One, the study analyzed blood samples collected from polar bears in the region between 1987-1994 and again between 2008-2017. Findings reveal alarming increases in pathogen exposure for the bear population. While the bears aren’t currently showing signs of severe illness, scientists express serious concern.

Why is This Happening? Changing Behaviors, Changing Environments

“We’ve observed this really rapid change in exposure that’s never before seen in polar bear populations to these particular pathogens,” said Karyn Rode, lead author of the study. “Essentially, climate change, and particularly sea ice loss, have forced polar bears in the Chukchi Sea region to spend more time on land.”

She further explains, “Females in the population are especially impacted as they spend a considerable amount of time ashore while they den and raise their cubs. The females consistently showed higher exposure rates for pathogens common to terrestrial environments. Their exposure correlates directly with increased onshore living due to the reduced availability of sea ice.”

More Than Just Polar Bears Affected? Concerns About Human Consumption

According to Rode, this phenomenon may signal broader shifts in disease transmission patterns within Arctic ecosystems.

“Polar bears themselves feed on animals which have probably also experienced exposure changes from these pathogens,” she stressed. “Within Inuit communities, polar bears remain a vital food source, so it’s important to investigate potential risks involved in consuming polar bear meat.”

“People who consume wild animals from a variety of sources already demonstrate cases of acquiring illnesses that originate in animals.” Rode cautioned.

Next Steps: A Need for Vigilance

While current research focused primarily on exposing polar bears, the U.S. Geological Survey plans further studies specifically exploring pathogen levels within bear meat. This investigation seeks to determine potential health risks posed to humans who consume polar bear meat. Understanding how climate change and ecosystem disruptions influence pathogen distribution across species is crucial to ensure healthy populations for wildlife, native communities, and our shared environment.

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