Unprecedented Mercury Levels Found in Alaska’s Coastal Wolves

A recent study highlights alarming mercury concentrations in wolves from Pleasant Island, located in the Alaska Panhandle region. Researchers compared these wolves to populations on the adjacent mainland and those from interior Alaska. Lead researcher Barst noted that Pleasant Island wolves present the highest mercury levels due to their unique diet, which includes a staggering 70% from sea otters. While mainland wolves primarily prey on moose, resulting in lower mercury exposure, this marine diet appears to significantly contribute to mercury accumulation.

Roffler, another researcher on the team, revealed that other wolf populations in Alaska and British Columbia are also consuming sea otters, indicating a potentially widespread dietary shift. “I was surprised it was happening at all,” Roffler commented, suggesting that this phenomenon may be more common than initially believed.

The study also draws connections between climate change and rising mercury levels. Barst explained that the retreat of Alaska’s glaciers—occurring at some of the fastest rates globally—releases mercury trapped in bedrock. “We don’t really know the fate of that mercury,” Barst said, noting the potential for it to enter the food web as methyl mercury.

Published in the journal Science of the Total Environment, the paper titled “Switching to marine prey leads to unprecedented mercury concentrations in a population of coastal Alaska wolves” underscores the urgent need for further investigation into these environmental changes and their ecological impact.

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