A captive population of greater vasa parrots at Lincolnshire Wildlife Park has been observed holding pebbles and date stones in the beak to grind calcium-rich dust from seashells. It’s the first record of any nonhuman animal using grinding technology. The parrots, which are native to Madagascar, may use the tools to protect their beaks from wear and tear.
The behaviour is most frequent just before the breeding season, when females require calcium to build their eggshells. During this period, their mates provision them with regurgitated food, which might help explain why the males seem to be the most enthusiastic grinders.