A new study of wild New Caledonian crows has used light-weight cameras mounted on their tails to capture live video of them creating hooked tools to extract insects from tree bark and leaf litter. It’s the first time that their renowned tool-making behavior has been caught on camera.
New Scientist’s website published a very intriguing article that provides the details:
New Caledonian crows are the only non-human animals to make hooked tools in the wild. Why they do so is something of a mystery. “The answer to that lies most probably in the ecology of the place and the ecology of these birds,” says Christian Rutz at the University of St Andrews, UK.
Filming their natural behaviour may help us get to the bottom of it.
The film captures crows manufacturing tools in the wild, which they did from paperbark and a local plant, Acacia spirorbis. They first snapped a twig just above and below a branch, then stripped the bark and leaves from the longer, thinner branch and crafted the cut ends to make a hook.
Crows used the hooks to extract insect larvae, and on one occasion an adult insect, from wood. They were also spotted using hooked tools to forage in leaf litter, which hasn’t been seen before.
The cameras also captured plenty of foraging behaviour without tools, including one bird catching a frog and feeding portions of it to chicks.
The research team released this fascinating video from their research:
For additional details, see the excellent article on the New Scientist website.
Source: NewScientist.com – “Crow cameras give a bird’s eye view of tool-making in the wild“
Featured Image Credit: Jolyon Troscianko