How many clams do bears eat?

Jun 8, 2015

Researchers at Katmai National Park have embarked on a new study to explore the link between brown bears and intertidal invertebrate.

Brown bears dig for clams at low tide.
Credit Courtesy of NPS

  Southwest Alaska brown bears love fish, we know that. We’ve all seen the iconic image of bears at a waterfall just waiting for a salmon to just jump right in their mouths, a bit less common is the image of a bear beach combing for clams and mollusks.

But eat them they do. Katmai National Park’s Chief of Resource Management Troy Hamon bears enjoy invertebrates and all kinds of other marine creatures.

“They actually scrap barnacles and eat barnacles. Everything you think a person might want to eat bears like, they’ll eat it," said Hamon. "And that includes wherever there is a good sources of these marine invertebrates.”

But Hamon and a team of researchers at Katmai say they don’t know to what extent they need to eat shellfish as part of their diet.

“I am excited to know if this is just a snack bar they graze by because it’s interesting and they like it like a bag of peanuts or is it an absolutely critical part of their feeding plan,” explained Hamon, adding that recently they collared 9 bears and will collar 10 to 12 more next year to monitor how much time they spent eating clams.

Bears aren’t the only thing attacking clams. Along with determining how much bears rely on clams for food, Katmai researchers are concerned about the effect of ocean acidification on these bear snacks. Hamon says clams and other shellfish are most at risk.

“Because it makes it harder for them, more difficult for them to create and maintain a hard shell, which they absolutely have to have to survive,” said Hamon.

Hamon says they’re not really sure how much brown bears rely on clams, mollusks, and other invertebrates for their diet. They hope to learn more about that during this study, which has an overall aim to provide a better understanding of the link between marine and terrestrial ecosystems.

Contact Matt Martin at (907)-842-2200 or matt@kdlg.org.