The Nuthatch’s Vertical World

The white-breasted nuthatch (Sitta carolinensis) is one of four species of nuthatch found in North America and is a year-round resident of our local mature hardwood and mixed forests. This compact, amusing little bird with absurdly short legs hitches headfirst down tree trunks as it searches for food, headed in the opposite direction of the brown creeper and our various woodpecker species. Its sharp, pointed bill probes among the crevices in the bark for insects and spiders, teasing out these tasty morsels that the other birds may have missed on their way up the trunk. (The nuthatch also enjoys acorns, as well as sunflower seeds, peanuts, and suet offered at feeders.) But once a meal is secured, how will the nuthatch eat it? Its bill is not equipped to crack open seeds, acorns, or crunchy insects, nor are its legs able to grasp the morsel while the bird hammers it open. Therefore, the nuthatch must rely on its vertical habitat to provide the means to prepare its meal. It flies to a furrowed tree trunk and wedges the tidbit into a crevice in the bark and proceeds to pound it open with its bill.

Wikimedia

The nuthatch nesting season is in full swing; you may have noticed vocal sparring as a pair of territorial nuthatches give their nasal “ank-ank” call in rapid succession as they oust another pair from their territory. Their visual displays may include brief chases or a spread of their very short tail feathers into a fan. 

Rick Cameron

Observe the pair for a while and you may find their nest cavity – usually a natural knot hole in a tree or an old woodpecker excavation, though sometimes nuthatches will use a nest box. The female has created a cup nest within made with bark strips, fine grasses, and animal fur. A fascinating aspect of nuthatch nesting is the bird’s ritual of grabbing an insect in its bill and, using a sweeping motion, rubbing the insect back and forth around the nest’s entrance hole. It is believed that the insects, usually beetles or ants, are specially chosen because they emit a noxious smell that persuades predators to look elsewhere for a meal. If food is plentiful and the odorous predator guard works, the nuthatch pair may fledge from five to ten youngsters in two weeks time. The fledglings will continue to be fed by their parents for another two weeks or so as they move through the forest - their vertical world.

Submitted by Cindi Kobak

(From the July Newsletter)