Longest tool-using parrot

The longest species of tool-using parrot is the hyacinth macaw Anodorhynchus hyacinthinus, which can attain a total length of up to 100 cm, and is native to South America's eastern and central regions, including portions of Brazil. This species has been repeatedly observed using tools to break open the hard-shelled nuts upon which it feeds. What the macaw does is wrap a piece of leaf around the nut before breaking it open with its beak, using the leaf to hold the nut in place, which might otherwise shift as the macaw attempts to break it open. In captivity, these macaws have also been seen using pieces of wood in a similar manner, as wedges, once again to hold the nut in place.

In the wild state, palm cockatoos Probosciger aterrimus in Polynesia use leaves as tools for the same purpose as hyacinth macaws do in South America. This is therefore a good behavioural example of convergent evolution – two entirely separate populations (and species) of bird independently evolving the same specific mode of behaviour in relation to the same specific stimulus, which in this case is the need to secure large heavy nuts in place when cracking them open.