do bears poop when they are hibernating
Science Alert

Do Bears Poop While Hibernating?

You can breathe easier now because the answer is finally here to the pressing question of our age: Do bears poop while they are hibernating? 

If a bear poops while hibernating and there's no one there to smell it, did it really happen?

Well, that's a word play on an old joke, but we can actually, probably, answer that question. Bears generally do not poop during hibernation. That might sound like something from a game of Trivial Pursuit, but it is nevertheless an interesting answer to a question you probably didn't even know you wanted to ask.

Here's how it works.

First, bears are either not "true hibernators" or they are "super hibernators," depending on who you talk to. They remain relatively alert throughout the hibernation phase, with high body temperatures and occasional waking periods. True hibernators lower their body temperatures and are in a practical coma during hibernation.

On the other hand, Brian Barnes, from the Institute of Arctic Biology at the University of Alaska Fairbanks, opines, "In my opinion, bears are the best hibernators." They can slow things like their heart rate from 55 beats per minute to only 9, and they can reduce their metabolic rate by up to 53%. 

"Their body is a closed system," says Barnes. "They can get through winter with only oxygen. It's all they need."

This ability to dramatically slow, but not coma-slow, their bodies puts the bears at an advantage for raising young and watching out for danger when they hibernate. But while hibernating, they are also able to avoid defecating.

To do this (or, not do this) they create a "poop plug." They create this plug unintentionally, although at one time, it was thought that they altered their diets toward the end of their pre-hibernation period in order to form the plug. Researchers have since found that not to be the case.

Even though a bear eats nothing during hibernation, intestinal secretions and cells continue to shed, producing fecal matter. This, along with hairs and even foot pad callouses that the bears ingest during grooming, create the poop plug.

The North American Bear Center indicates that, "During five to seven months in dens, bears accumulate feces in the lower 7-15 inches of the intestine to form a 'plug' 1.5 to 2.5 inches in diameter. The fecal plug is simply feces that have remained in the intestine so long that the intestinal walls have absorbed the fluids out of it, leaving it dry and hard."

But when you gotta go you gotta go, and as the hibernation cycle nears its end the bears do their thing. "By the sixth or seventh month in the den, most of these bears defecate—usually near the den entrance. Fecal plugs have a light odor that is not unpleasant," says the Bear Center.

That's got to be a very satisfying, er, moment for the bears.

Like what you see here? You can read more great articles by David Smith at his facebook page, Stumpjack Outdoors.

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