Most ornithologists believe there are somewhere between 9,000 and 10,000 species of birds in the world. Out of all of these species, only 270 actually use tools. Remarkably, the brown-headed nuthatch is the only North American bird that regularly uses tools.
The tool most often employed by the bird is a bark scale. The bird uses scales as a pry bars. Holding a scale in its long, slender beak, red-breasted nuthatches insert this primitive tool under a scale firmly attached to a tree. It then tries to pry the stubborn scale loose from several directions trying to uncover hidden foods such as caterpillars, spiders, cockroaches, and other invertebrates.
More often than not, if a nuthatch is successful in dislodging a scale, it will immediately drop the scale held tightly in its beak. However, at times, a bird will use the same scale to wedge loose three to four scales before discarding the slender tool. Those observers lucky enough to witness the remarkable behavior have reported brown-headed nuthatches will use up to three tools during a feeding event.
I should note that, in addition to bark scales, nuthatches have also been seen employing pine needles and twigs as tools.
Both adult and young nuthatches use tools to obtain food. However, as far as we know, young nuthatches only employ tools during the first few months after they fledge.
It appears that this tiny nuthatch engages in this behavior most often while looking for food in longleaf pine trees. This could be because the birds can more easily remove the flaky scales found on the trunks of these trees than the scales covering other trees. Who knows?
At any rate, be on the lookout for this behavior in your backyard. Since we know so little about this fascinating behavior, anything you see in your backyard could enhance our knowledge of the behavior of this energetic, feisty backyard resident.