NUTHATCHES AND WALL CREEPERS: Sittidae

PHYSICAL CHARACTERISTICS

Nuthatches and wall creepers consist of three groups: typical nuthatches, sittellas, and wall creepers. They are small and stocky, large-headed, short-tailed perching birds. Nuthatches are 3.5 to 7.5 inches (8.5 to 19.0 centimeters) long. They have a compact body, large head, short neck, and a thin, chisel-shaped, slightly upturned bill. Their long, pointed wings have ten primary feathers each, they have a short, squared tail, short legs and strong, long toes that have sharp claws. Nuthatches have blue-gray upperparts (blue in some tropical species) and white, pale gray, or reddish brown underparts. The crown on the top of the head is dark and there is a white stripe over the eye.

Sittellas are 4.3 to 4.8 inches (11 to 12 centimeters) long. They have a compact body, large head, thin, chisel-shaped bill and a short tail. They also have a brown-streaked or black body with a red face. Wall creepers are about 6.5 inches (16 centimeters) long. They have a compact body and strong, slightly down-turned bill, a rather long claw on its hind toe and a short tail. Sittellas have brownish upperparts, white underparts (with brown streaks), a white throat, and a brownish yellow patch around the eyes.

GEOGRAPHIC RANGE

Nuthatches and wall creepers are distributed throughout North America, Eurasia, Africa, Southeast Asia, and Australasia (region consisting of Australia, New Zealand, New Guinea, and the neighboring islands of the South Pacific).

HABITAT

They inhabit mostly coniferous, deciduous, and mixed forests and woodlands, while others live in rocky scrublands.

DIET

Nuthatches and wall creepers eat mostly invertebrates (animals without backbones) such as insects, snails, spiders, and other similar animals. They forage (look for food) by climbing up and down on trees while using their bills to pick loose bark away in order to locate their prey on the surface and crevices (narrow cracks) of tree trunks. Nuthatches and wall creepers are the only tree-trunk foraging birds that climb up trees with their head downwards instead of upwards (thus, finding food missed by other birds such as woodpeckers). They climb back down by holding themselves with one foot on the bark while moving with the other, switching feet positions as they zigzag in their path. Foraging on rocks and in epiphytic mosses and lichens (plants that grow on another) also occurs. Arthropods (invertebrate animal with jointed limbs) are sometimes found in foliage from the ground or while in flight. During the winter, they also eat small fruits and seeds. Nuthatches and wall creepers use their bills to crack open seeds by wedging the seed into a small crevice and hitting it with the top of their bill. When food is plentiful, they store it for later use.

BEHAVIOR AND REPRODUCTION

Nuthatches and wall creepers fly in an up-and-down motion. Most birds are not migratory. Adult pairs are monogamous (muh-NAH-guh-mus; having one mate) and occupy a permanent territory throughout their lives. Nests are made in natural cavities in trees or in cavities that were dug out and abandoned by woodpeckers. When previously used nests are used, they will often narrow the opening with mud, dung (solid excrement of animals), and other sticky substances in order to keep predators and competitors out. Some nests are made in rock cavities with substances such as bark flakes and leaves. Many sittellas build open nests in trees rather than using holes. Females lay four to ten white eggs that are flecked with brown or red. Only females sit on the eggs, but both males and females feed the chicks. Most birds produce only one brood each year.

NUTHATCHES, WALL CREEPERS, AND PEOPLE

People do not have any direct, significant relationship with nuthatches and wall creepers, other than the enjoyment that birdwatchers receive from viewing them. They often nest in birdhouses built by people and eat out of provided feeding stations.

CONSERVATION STATUS

Two species in this family are considered Endangered, facing a very high risk of extinction; two species are considered Vulnerable, facing a high risk of extinction; and two species are considered Near Threatened, in danger of becoming threatened with extinction.

RED-BREASTED NUTHATCH (Sitta canadensis): SPECIES ACCOUNTS

Physical characteristics: Male red-breasted nuthatches have blue-gray upperparts (back, shoulders, wings, and rump) with red-brown to buffy orange under parts. They have a black cap and nape (back part of neck), a white throat, a white stripe over the eyes and a black stripe through them. The male nuthatches also have a blue-grey short tail (which shows a white band near the ends). Females are similar to males except for a dark gray crown and nape, and lighter buff under parts that are rustier on the sides of the lower body and the feathers beneath the wings. They are 4.0 to 4.7 inches (10.2 to 11.9 centimeters) long, with wings that are 8.0 to 8.5 inches (20.3 to 21.6 centimeters) wide. They weigh about 0.35 ounces (10 grams).

Geographic range: Red-breasted nuthatches are found throughout southern and northwestern Canada and most of the United States (and found very infrequently in Florida and the southern parts of the Southwest, usually only during the winter months).

Habitat: Red-breasted nuthatches inhabit dense coniferous forests (such as balsam fir and spruce), mixed coniferous-deciduous forests, and along rivers within such forests, moving northward into the high mountains during breeding season. They may also be found in other types of forests, especially during their fall migration.

Diet: They eat invertebrates such as beetles, wasps, caterpillars, insect eggs, and crane flies from tree bark and foliage. In winter, they also eat fruits, nuts, and seeds (especially of pines, spruces, firs, and other conifers). The birds wedge food in tree bark crevices with their bills, and then break off pieces before eating them. They use the head-down movement as they climb trees, as opposed to the normal way of climbing trees head first (head-up).

Behavior and reproduction: Red-breasted nuthatches are rather quiet and tame birds. They are normally found as pairs who defend a breeding territory. Considered an irregular migratory bird, they sometimes spend winters in breeding areas when food is plentiful. At other times during the fall, large numbers of the birds move south together and into lowlands, especially when food supplies are low. They produce calls that sound like a nasal "hennk-jemml," which is quite high-pitched but soft. Other calls include "it-it-it" and "ank-ank-ank." Their song is a high-pitched "wa-wa-wa-wa-wa" or "eeeen-eeeen-eeeen."

Males court females by feeding them. The male's courtship rituals also include turning his back to her, and then lifting his head and tail, raising back feathers and drooping wings, and swaying from side to side. The monogamous breeding pair uses cavities of trees (often pine and cottonwood) for their nests, along with old woodpecker holes and bird boxes. Nests are from 5 to 100 feet (1.5 to 30.5 meters) off the ground but usually 15 feet (4.5 meters). The inside of the nest is lined with grasses, mosses, rootlets, shredded bark, and plant fibers. Females lay four to seven eggs (which are peppered and spotted with different shades of brown) from April to June. Females sit on the eggs for an incubation period (time of sitting on eggs) of about twelve days, but males join females in feeding of the young. Fledging period (time it takes for the young to grow flying feathers) is eighteen to twenty-one days.

Red-breasted nuthatches and people: Red-breasted nuthatches will often eat out of the hands of people who feed them.

Conservation status: Red-breasted nuthatches are not threatened, being fairly common to common in most of its range. Its eastern breeding range is expanding southward. ∎

NUTHATCH (Sitta europaea): SPECIES ACCOUNTS

Physical characteristics: Nuthatches have blue-gray upperparts, rusty under parts, brown to white undersides, a blue-gray crown, a white throat, and a black line through the eyes with a white line above them. Coloration varies greatly due to the species' very large range. Females and juveniles have a duller head coloring and paler under parts. They are 5.5 inches (14 centimeters) long, with a short tail, and weigh 0.7 to 0.9 ounces (20 to 25 grams).

Geographic range: The birds range widely in temperate Eurasia, from the western coast of the Atlantic Ocean to the eastern coast of the Pacific Ocean. They have the most extensive range of all nuthatches.

Habitat: Nuthatches are located in mature temperate forests, from deciduous to coniferous ones.

Diet: Nuthatches eat invertebrates, such as insects, from tree bark and foliage, especially from branches. They also eat fruits, nuts, and seeds during winter months. Nuts are wedged into crevices and then broken open with hits from the bird's bill.

Behavior and reproduction: Nuthatches are often seen running along tree branches or up and down trunks in search of insects. They occur as pairs that defend a breeding territory. The birds do not migrate. During the nonbreeding season, nuthatches are seen in flocks with many different species. Pairs nest in cavities and holes of trees. Nests are cup-shaped and made of bark flakes. The entrance to the nest is often plastered with mud to reduce its size to the width of the female's body, in order to deter enemies. Females sit on the eggs, but both sexes feed the chicks.

Nuthatches and people: People and nuthatches have no known significant relationship.

Conservation status: Nuthatches are not threatened, being common throughout their habitat. ∎

FOR MORE INFORMATION

Books:

Alsop, Fred J. III. Birds of North America. New York: DK, 2001.

Baughman, Mel M., ed. Reference Atlas to the Birds of North America. Washington, DC: National Geographic, 2003.

del Hoyo, Josep, Andrew Elliott, Jordi Sargatal, Jose Cabot, et al, eds. Handbook of the Birds of the World. Barcelona: Lynx Edicions, 1992.

Dickinson, Edward C., ed. The Howard and Moore Complete Checklist of the Birds of the World, 3rd ed. Princeton, NJ and Oxford, U.K.: Princeton University Press, 2003.

Field Guide to the Birds of North America, 4th ed. Washington, DC: National Geographic Society, 2002.

Harrison, Colin James Oliver. Birds of the World. London, U.K. and New York: Dorling Kindersley, 1993.

Forshaw, Joseph, ed. Encyclopedia of Birds, 2nd ed. San Diego, CA: Academic Press, 1998.

Kaufman, Kenn, with collaboration of Rick and Nora Bowers and Lynn Hassler Kaufman. Birds of North America. New York: Houghton Mifflin, 2000.

Sibley, David. The Sibley Guide to Birds. New York: Alfred A. Knopf, 2000.

Terres, John K. The Audubon Society Encyclopedia of North American Birds. New York: Knopf, 1980.