Itsy Bitsy Mercury Crept Up the Polar Bear’s Snout

Photo courtesy US Fish and Wildlife Service

For indispensable reporting on the coronavirus crisis, the election, and more, subscribe to the Mother Jones Daily newsletter.


We all know polar bears are suffering from a melting Arctic. We know they’re being found far out at sea, far from shore. Some have been seen drowning.

Well now it turns out the loss of their mobile ice islands isn’t the only problem. A warming world may well be poisoning them too. In ways no one  imagined.

Here’s how: A new study in the journal Polar Research has made the important finding that polar bears feed from one of two different food webs. Each contains mercury. But one is worse than the other.

  • The phytoplankton food web derives from the free-floating single-celled plants inhabiting the sunlit layer of ocean.
  • The ice algae food web derives from the microscopic plants living on the underside of the icepack covering the frozen ocean.

The researchers figured out which was worse by teasing data from hundred-year-old museum samples of polar bears. They analyzed late-19th- and early-20th-century polar bear hair for the chemical signatures of nitrogen isotopes, carbon isotopes, and mercury concentrations.

In other words, they took a look back in time to the period before anthropogenic mercury emissions escalated ferociously.

What they discovered was that the polar bears who get most of their nutrition from the phytoplankton-based food webs carry heavier mercury burdens that those who feed primarily on ice algae-based food webs.

A finding that does not bode well for polar bears living in an increasingly iceless world.

Listen up, Copenhagen. It’s not about the weather.
 

SIX TRUTHS

Reclaiming power from those who abuse it often starts with telling the truth. And in "This Is How Authoritarians Get Defeated," MoJo's Monika Bauerlein unpacks six truths to remember during the homestretch of an election where democracy, truth, and decency are on the line.

Truth #1: The chaos is the point.

Truth #2: Team Reality is bigger than it seems.

Truth #3: Facebook owns this.

Truth #4: When we go to work, we're in the fight.

Truth #5: It's about minority rule.

Truth #6: The only thing that can save us is…us.

Please take a moment to see how all these truths add up, because what happens in the weeks and months ahead will reverberate for at least a generation and we better be prepared.

And if you think journalism like Mother Jones'—that calls it like it is, that will never acquiesce to power, that looks where others don't—can help guide us through this historic, high-stakes moment, and you're able to right now, please help us reach our $350,000 goal by October 31 with a donation today. It's all hands on deck for democracy.

payment methods

SIX TRUTHS

Reclaiming power from those who abuse it often starts with telling the truth. And in "This Is How Authoritarians Get Defeated," MoJo's Monika Bauerlein unpacks six truths to remember during the homestretch of an election where democracy, truth, and decency are on the line.

Truth #1: The chaos is the point.

Truth #2: Team Reality is bigger than it seems.

Truth #3: Facebook owns this.

Truth #4: When we go to work, we're in the fight.

Truth #5: It's about minority rule.

Truth #6: The only thing that can save us is…us.

Please take a moment to see how all these truths add up, because what happens in the weeks and months ahead will reverberate for at least a generation and we better be prepared.

And if you think journalism like Mother Jones'—that calls it like it is, that will never acquiesce to power, that looks where others don't—can help guide us through this historic, high-stakes moment, and you're able to right now, please help us reach our $350,000 goal by October 31 with a donation today. It's all hands on deck for democracy.

payment methods

We Recommend

Latest

Sign up for our free newsletter

Subscribe to the Mother Jones Daily to have our top stories delivered directly to your inbox.

Get our award-winning magazine

Save big on a full year of investigations, ideas, and insights.

Subscribe

Support our journalism

Help Mother Jones' reporters dig deep with a tax-deductible donation.

Donate