New Caledonian Crows Are Handy Tool Makers
In a hooray moment for bird scientists studying crows, researchers have videoed New Caledonian crows using tools. The footages could explain what sets these fascinating birds apart.
According to BBC, New Caledonian crows have been largely studied in cages and at bait sites given that the terrains they inhabit are often difficult for researchers to access. In the study described in Biology Letters, scientists fixed cameras on tail feathers of 19 wild Caledonian crows to study them. Ten cameras were retrieved and four showed researchers that the birds make tools for use!
"Our video recordings reveal an 'expanded' foraging niche for hooked stick tools, and highlight more generally how crows routinely switch between tool- and bill-assisted foraging," the researchers wrote in the journal.
In the videos, researchers saw the birds making hooked tools from twigs to use them for foraging for ants, wood-boring insect larvae and insects.
The study's co-author Christian Rutz told Sacramento Bee that NC crows were earlier seen making such tools but the practice in wild was not caught on camera. Analysis of the video data collected by Rutz's team showed that tool-related foraging accounted for 19 percent of all foraging behavior seen on 10 hours of footage.
While the videos have documented the crows' surprising behavior, which until now was largely associated with primates, they also threw many questions. For one, why were other individuals not seen using tools, and another important question that requires further research - what is the motivation behind tool use?