Quirks and Quarks

Parrot Tool Use Is a Grind

Parrots use pebbles to grind seashells into powder, then eat the calcium, which may supply material for eggshells

Parrots use pebbles to harvest calcium by grinding seashells into powder

Greater Vasa Parrot (Frank Wouters, cc-by-2.0)
The Greater Vasa Parrot is native to Madagascar. Unlike their colourful, talkative relatives, these parrots are a drab gray colour, although they are very social and playful. But a new study by Megan Lambert, a PhD student in the Department of Psychology at the University of York in England, has found that this species of parrot has joined the elite group of avian tool users.

In a laboratory setting, Greater Vasa parrots - four males and one female - were observed taking small pebbles or date pits into their beaks and grinding them on the inside of seashells, or using them for breaking off small fragments of shell. The resulting calcium powder and fragments from the shell were then ingested by the birds.

The calcium is likely required for the female parrot's own production of eggshell. It is not known why the males need the calcium.

Related Links

Paper in Royal Society Biology Letters
- University of York release
- University of St. Andrews release
- National Geographic blog