Do bears scratch in the woods? Absolutely – check out the comic clip of tree-rubbing brown bears, filmed for Planet Earth II below
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Why do bears scratch?
Bears routinely use trees, boulders and even signposts as back scratchers, but this is more than dealing with an ursine itch. They are also scent-marking, so select prominent trees, preferably where territories overlap.
Many aspects of the chemical signalling – where, when, how much, how often – differ according to the bears’ sex and age.
The perfume is far from subtle. Alaska state biologist Anthony Crupi has studied ‘rub trees’ by placing gauze over the trunk, and it “would turn almost black from the oils and stuff in the bears’ fur… it really smells like bear.”
By establishing hierarchies, scent-marking reduces conflict. Brown and black bears also mangle trees along favoured routes, some of which bleed sap. Curved claws further scar the bark with hormonal graffiti.
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Image and video @ BBC