Image: Volker Deecke
Just like Baloo said to Mowgli in The Jungle Book, look for the bare necessities, the simple bare necessities. Forget about your worries and your strife. That's why a bear can rest at ease, with just the bare necessities of life ... which in this case includes a barnacle-covered rock, perfect for scratching fur:
In July 2011, Volker Deecke of the University of Cumbria, UK, was on holiday in Alaska's Glacier Bay national park when he spotted a brown bear in shallow water. The animal picked up a small, barnacle-covered rock, turned it around a few times then rubbed the rock over its face for a minute. It repeated this with another rock (Animal Cognition, DOI: 10.1007/s10071-012-0475-0).
The bear was moulting, and had big patches of fur hanging off its skin. Moulting bears often scratch themselves with their claws, or rub their bodies against trees or rocks. "The barnacles," Deecke says, "may have given that exfoliating feeling."