So there you are, trundling through the forest. A powerful black bear, lord of the food web, you’re eating up berries, maybe catching some fish, when, all of a sudden, you’re being eaten by a massive grizzly.
That scene, or something like it, played out in Banff National Park in Alberta, Canada, earlier in August, when hikers came across a grizzly eating a black bear.
The U.S. Fisheries and Wildlife Service says that grizzly bears are opportunistic omnivores:
It will eat plants, as well as insects and other animals. Scavengers by nature, grizzlies spend most of their waking hours searching for food. Forbs, roots, tubers, grasses, berries and other vegetation, and insects comprise most of the bear’s diet. But grizzlies are very adaptable, finding and subsisting on a variety of foods if necessary.
In Yellowstone this means moths, snapped up by the tens of thousands. In Banff, apparently, it means other bears.
Steve Michel, who works at Banff, says “he suspects the kill was opportunistic,” says the CBC.
“Grizzly bears are opportunistic hunters,” he said. “They will take advantage of any food source that presents itself.”
Bears eating other bears isn’t entirely new—polar bears will eat each other, especially each others’ young. But for grizzlies it’s much more novel. Though how novel is up for debate. Michel told the CBC that he “knows of four other instances when a grizzly has hunted, killed and eaten a black bear in Banff.”
“It may not be as rare as we think it is,” he said. “But it is rare that we actually are able to document it. We tend not to know about it all.”
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