A video released by the Arizona Game and Fish Department shows just how vicious bears can be when they think they are threatened.
A bear cub estimated to be 6 months old or younger is seen running and climbing up a tree in the video shot by Jose Valenzuela in June near Riggs Lake on Mt. Graham in the southeast part of the state.
As the cub climbs, a much larger, faster bear enters the frame and, within a matter of seconds, climbs the tree, grabs the cub and slams it to the ground.
"It looks like not only was the cub killed, it was consumed," said Mark Hart, a public information officer with AZDGF. "That’s a rare look into how brutal Mother Nature can be."
Hart said a cub that young would normally be accompanied by its mother, who likely would have tried to intervene. But there was no mother around to protect the cub.
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"A sow wouldn't do that to another cub, but this is fairly typical of male bear behavior," Hart said.
Hart and AZDGF suspect that the adult bear may have seen the cub as a threat to his mating pool, even if that threat would come years down the line.
But this bear isn't much of a threat to humans -- the person filming is in bear country, rather than the bear being in an area with a lot of human traffic. That's why though Game and Fish responded to the area, the department isn't searching for this bear; those that wander into populated areas are more likely to threaten people.
"If they’ve developed a taste for dumpster diving, they don’t want fruits and nuts anymore," Hart said.
Though northern Arizona (from Pinetop to Flagstaff) sees the most bears in the state, there are plenty in southeast Arizona, mostly at 5,000 feet or above.
Hart said that statistically, Arizonans are twice as likely to be injured by a bear than by a mountain lion, meaning it's important to report bear sightings to authorities.
"The only way we can deal with problem bears is if the public lets us know," Hart said.
If you spot a bear, you can reach the Arizona Department of Game and Fish at 623-236-7201.