Bear Meets Bear

Theodore Roosevelt: The American grizzly is a symbol of the American character: strength, intelligence, ferocity. Maybe a little blind and reckless at times... but courageous beyond all doubt. And one other trait that goes with all previous.

Reporter:  And that, Mr. President?

Theodore Roosevelt: Loneliness. The American grizzly lives out his life alone. Indomitable, unconquered - but always alone. He has no real allies, only enemies, but none of them as great as he.

Reporter: And you feel this might be an American trait?

Theodore Roosevelt: Certainly. The world will never love us. They respect us - they might even grow to fear us. But they will never love us.

- The Wind and the Lion (1975)

Few experiences are more daunting for a zookeeper than sliding open the shift door that will put two bears - especially an adult male and an adult female - together in the same space for the same time.  Bears are extremely powerful animals, and the males tend to dwarf the females, sometimes being twice as large.  They are also largely solitary.  When brought together, there always remains the possibility that a fight will break out and that it will prove fatal.  Such was the case just a few months ago at a polar bear introduction in Detroit.  I'm sure it was on the minds of the polar bears keepers introducing bears in Chicago recently, seen in the video above.

Bears might not be as solitary as we often give them credit for being, though.  They just want what they want, which usually is food.  They can be very food aggressive and defensive of food resources.  In situations where food is at least temporarily plentiful, however, they can be quite tolerant of one another.  There's no better image of that than a northern salmon stream, where brown bears are packed cheek-to-jowl standing in the water catching fish.  Similar sights have been reported for polar bears gorging on a whale carcass, or black bears in a farmer's fields.

In zoos, where food is abundant and provided regularly, bears may be even more tolerant of each other's company.  In fact, without the activity associated with walking great distances and searching out unpredictable little tidbits or unexpected bonanzas of food, the bears may actually prefer having each other around for companionship and stimulation.   A zoo environment will inevitably find itself deprived compared to the wild in some respects, so it should always try to offset these deficiencies when it can.  I've seen some ridiculously large social groups of bears in zoos, seemingly peaceable.

That doesn't mean any bear introduction can be taken for granted.  They need to be set up for success.  Plenty of space.  Gradual introductions - olfactory, auditory, visual, and then perhaps even tactile contact (through bars or mesh) before full introductions.  Hiding options and escape routes (female bears tend to be smaller than males, which means that in many cases they are better, more agile climbers).  Striking a balance between close observation (to intervene if something goes wrong) and privacy (to reduce stress).

And still, even when everyone does everything right, everything can still go wrong in the blink of an eye... though thankfully not in the case of the video above.