In Images: Polar Bears' Shifting Diet

arctic habitats, environment
Two polar bears seen on the Arctic ice during a research cruise to map the ice in 3D. (Image credit: Scott Sorensen)

Changing habitat

Polar bear walking on a frozen pond with blowing snow near Cape Churchill, Canada.

(Image credit: Hansruedi Weyrich)

As the climate has changed, polar bears have shifted their diets in response, several new papers published in 2013 showed.

Melting sea ice

sea ice

(Image credit: Evgeny Kovalev spb | Shutterstock)

Declines in sea ice have meant that polar bears in the western Hudson Bay cannot hunt their main prey for longer stretches of the year.

Preferred prey

polar bear with seal carcass

(Image credit: ©AMNH/R. Rockwell)

Historically, polar bears have mainly hunted for seals in gaps in the sea ice.

Snow geese

snow geese

(Image credit: Igor Kovalenko | Shutterstock.com)

When the sea ice melts in summer, polar bears come ashore. Then they also eat land-based foods such as snow geese.

Scat-sniffing dog

dog with polar bear scat

(Image credit: ©AMNH/R. Rockwell)

To see how climate change had affected polar bear diet, Linda Gormezano, a researcher at the American Museum of Natural History, and her colleagues, used a Dutch Shepard dog named Quinoa to find polar bear scat.

Ice dog

dutch shepard dog on ice flow

(Image credit: ©AMNH/L. Gormezano)

The dog found many piles of scat, and the team analyzed the contents.Here, quinoa sniffs for scat on an ice flow.

New diet

Caribou mom and calf, camera trap

(Image credit: WCS)

Compared to the 1960s, the polar bear diet had changed. They now prey upon caribou, whose populations have boomed in the area

Caribou carcass

polar bear eats caribou

(Image credit: ©AMNH/R. Rockwell)

Here, a polar bear with a caribou carcass.

Goose eggs

goose eggs

(Image credit: Dragon_Fang | Shutterstock.com)

Because the polar bears come ashore earlier, they are now on land when lesser snow geese are nesting, and now eat goose eggs as well.

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Tia Ghose
Managing Editor

Tia is the managing editor and was previously a senior writer for Live Science. Her work has appeared in Scientific American, Wired.com and other outlets. She holds a master's degree in bioengineering from the University of Washington, a graduate certificate in science writing from UC Santa Cruz and a bachelor's degree in mechanical engineering from the University of Texas at Austin. Tia was part of a team at the Milwaukee Journal Sentinel that published the Empty Cradles series on preterm births, which won multiple awards, including the 2012 Casey Medal for Meritorious Journalism.