A Kea parrot named Bruce at Willowbank Wildlife Reserve in Christchurch, New Zealand, was found in 2013 missing his upper beak and learned to use small pebbles held between his tongue and lower beak to preen his feathers.

The Parrot Who Invented a Tool. Bruce the kea arrived at a New Zealand reserve in 2013. His upper beak was gone, likely from a pest trap. Staff worried he could not preen. Then keepers noticed something strange. Bruce picked up small pebbles. He wedged them between tongue and lower beak. Then combed his feathers, one stone at a time.