First evidence of tool use by greater vasa parrots (Coracopsis vasa)
Date: December 16, 2015
Source: University of York
Psychologists at the University of York and University of St Andrews have uncovered the first evidence of tool use by greater vasa parrots (Coracopsis vasa).
Studying ten captive parrots, researchers in the Department of Psychology at York observed the birds adopt a novel tool-using technique to acquire calcium from seashells and also the active sharing of tools among themselves.
The birds used small pebbles or date pits to grind calcium powder from the shells or to break off small pieces of shell to ingest. This behaviour, never before seen in this species, is the first evidence of a nonhuman using tools for grinding, and one of the few reports of nonhuman animals sharing tools directly.
Observing and filming the parrots over an eight month period (March to October), researchers documented their interactions with cockle shells on the floor of their aviary. Shells are a known source of calcium for birds.
Five out of ten birds were documented using tools, placing either pebbles or date pits inside shells to grind against the shell, or using them as a wedge to break apart the seashell.
Interest in the shells was greatest from March to mid-April, just before the breeding season -- this may be due to calcium supplementation being critical for egg-laying. Researchers were therefore initially surprised to find that it was the males, not the females who showed the greatest interest in shells.