Sitta pusilla

Geographic Range

Brown-headed nuthatches ( Sitta pusilla ) are endemic to the southeastern United States. They are found as far north as Virginia, as far west as Texas and as far south as southern Florida. There is also a small, declining population found on the Grand Bahama Islands.

• Biogeographic Regions
• nearctic nearctic
  • native native
• neotropical neotropical
  • native native

Habitat

Brown-headed nuthatches are typically found in open mature pine stands with thin understories. Areas with frequent prescribed burns are ideal for these birds as it keeps the understory open and creates snags for nesting. Brown-headed nuthatches create nesting areas by excavating holes in pine trees or by using abandoned woodpecker cavities or birdhouses. Typically, these birds are found below 700 m in elevation.

• Habitat Regions
• temperate temperate
• terrestrial terrestrial

• Terrestrial Biomes
• forest forest

• Other Habitat Features
• urban urban

Physical Description

Brown-headed nuthatches are monomorphic, meaning males and females have a similar size and color. Juveniles also resemble adults in coloring and size. They range in length from 105 to 110 mm from crown to tail, with an average adult mass of 10.8 g. They have an average wingspan of 16 to 18 cm. Their coloring consists of a dull brown crown and a whitish nape. Their back, wings, rump and tail are blue gray with darker slate colored remiges (flight feathers) and rectrices (steering feathers) with white markings. Brown-headed nuthatches are dull white from their chin to their undertail. They have a distinct black bar crossing horizontally through their eyes, with black irises. Their long, thin beaks are black and pointed, allowing them to use bark as a tool to pry food from trees.

• Other Physical Features
• endothermic endothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• sexes alike

Reproduction

There is very little information available regarding mate choice in brown-headed nuthatches, however, once a mate is chosen, they are normally pair bonded for the season and frequently for life. The male chooses a cavity to excavate and then, partnering with the female, they start excavation. Taking turns in 20 to 30 minute increments, the male and female chip away a hole for their chosen nest. Several nests may be abandoned before one is settled upon. Brown-headed nuthatches are a cooperative breeding species. In addition to the breeding male and female, there are 1 to 3 helper birds that help with nest building, feeding and nest defense.

• Mating System
• monogamous monogamous
• cooperative breeder cooperative breeder

Brown-headed nuthatches are cooperative breeding birds, meaning they rear their young in groups of 2 to 5 adult birds per nest. The group includes the parents and the non-breeding "helper" birds. Non-breeding birds help with nest excavation, defense, preening and feeding. Brown-headed nuthatches start building nests in February. Generally they are located in snags (dead trees), birdhouses or abandoned woodpecker holes. Most new nests are built within 100 meters of the previous year’s nest, although they may remain in the same nest each year. Suitable nest sites include trees with hard exteriors and soft interiors that they can easily excavate. The nest opening is usually less than 2.5 cm in diameter. The nest itself is at least 30 cm deep and less than 3 meters from the ground, which may leave it vulnerable to predation. The inside is filled with hair, decayed wood and shredded cocoons. The eggs vary in shape and color and can be laid from March to July. Generally 4 to 8 eggs are laid per brood. Females incubate and guard the eggs, while the male brings food and additional nest materials as needed. This process takes around 14 days. Once the young hatch, they remain in the nest and are cared for by the adults for another 17 to 19 days. If a nest fails, the breeding pair will not re-nest that season. Instead, they might help another breeding pair with their nest.

• Key Reproductive Features
• iteroparous iteroparous
• seasonal breeding seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• oviparous oviparous

Brown-headed nuthatches start building nests between February and April. They start and abandon several nests before deciding upon a nest. After the eggs are laid, the female stays in the nest during the incubation period, which lasts about 14 days. She guards the eggs and keeps them warm, while the male and helpers bring her food and additional nest lining if necessary. Once the eggs hatch, nestlings are dependent on both parents and the helpers for food and protection from predators. Nestlings fledge around 18 to 19 days after hatching but remain dependent upon their parents for food for about 32 days. Even after food independence, they remain close to their parents for an unknown amount of time.

• Parental Investment
• male parental care male parental care
• female parental care female parental care
• pre-hatching/birth
  • provisioning
    • male
    • female
  • protecting
    • female
• pre-weaning/fledging
  • provisioning
    • male
    • female
• pre-independence
  • provisioning
    • male
    • female
  • protecting
    • male
    • female

Lifespan/Longevity

Brown-headed nuthatches have an average lifespan of 8 years in the wild; the longest recorded lifespan for the species was 9 years. In captivity the maximum-recorded lifespan is 6 years.

Behavior

Brown-headed nuthatches are a social species, traveling in small single-species flocks of 4 to 5 birds during the breeding season. During the non-breeding season, they travel in multi-species flocks of 8 to 20 birds. Other bird species in the multi-species flocks commonly include Carolina chickadees , downy woodpeckers , brown creepers , golden-crowned kinglets , tufted titmice and pine warblers . Among these species, the only birds brown-headed nuthatches compete with are pine warblers. They normally feed in different parts of the pines, but occasionally their territories overlap. Brown-headed nuthatches are very territorial and prevail over pine warblers in confrontations. They also engage in a social habit called allopreening, a form of preening between birds. Brown-headed nuthatches only do this with members of their own species. This behavior may serve a hygienic function, establish relationships and possibly reduce stress and aggression. Brown-headed nuthatches are the only species in family Sittidae that have been observed using tools. They pry off a loose piece of bark and use it as a wedge to pry off more difficult pieces of bark. When they have finished prying bark, they drop the wedge and investigate the revealed surface, looking for insects to eat. They are also known to wedge a seed into a bark depression and hammer it with their beaks until the seed cracks.

• Key Behaviors
• arboreal arboreal
• flies
• diurnal diurnal
• motile motile
• sedentary sedentary
• territorial territorial
• social social

Home Range

The home range of brown-headed nuthatches varies from 0.3 to 47.6 hectares, with an average territory size of 7.1 hectares.

Communication and Perception

Brown-headed nuthatches are able to cheep within one day of hatching. This sound is audible for 15 m and is likely used to gain the attention of their parents. Adult brown-headed nuthatches have several main vocalizations used for long distance communication, close communication and warnings solely between mates and during courtship. Their main call is a 2-syllable sound, which sounds like a squeaky rubber ducky, 'tyah-dah or chee-da'. The cheep can be more or less emphatic depending on their level of excitement; it is the only call that is heard for long distances and is most likely used specifically for distance communication. They also have several variations of a soft, low chirp that can only be heard when they are close together. This is often used when the birds are foraging or one is approaching a nest. When danger is perceived, brown-headed nuthatches emit a sharp, single-note alarm call.

• Communication Channels
• acoustic acoustic

• Other Communication Modes
• choruses choruses

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

In the warmer months, brown-headed nuthatches primarily eat insects such as cockroaches , grasshoppers , moths , beetles , ants and spiders . They also consume beetle larvae, insect egg cases and sunflower seeds. When food is too big or unwieldy to eat, they carry it to another location and hammer it until it is ready to eat. In the colder months when insects are scarce, they eat pine seeds and break open pinecones to reach the seeds. These birds are known to cache seeds by hiding them underneath flakes of bark on trunks or limbs of pines.

• Primary Diet
• carnivore carnivore
  • insectivore insectivore
• herbivore herbivore
  • granivore granivore

• Animal Foods
• eggs
• insects
• terrestrial non-insect arthropods

• Plant Foods
• seeds, grains, and nuts

• Foraging Behavior
• stores or caches food stores or caches food

Predation

Since their nests are found so close to the ground, brown-headed nuthatches are often preyed on by snakes and other animals such as raccoons , domestic cats , squirrels and larger birds. They have no active defense, but to protect the eggs and hatchlings, females guard the nest constantly to keep predators at bay.

Ecosystem Roles

Brown-headed nuthatches are parasitized by a nematode species, Oxyspirura pusillae . They are also parasitized by protozoan blood parasites from the genera Haemoproteus and Plasmodium . Plasmodium is the genus responsible for malaria in humans.

Economic Importance for Humans: Positive

Brown-headed nuthatches do not have a direct impact on humans. However, they are a reliable indicator of pine ecosystem health in the southeastern United States. The declining population of brown-headed nuthatches has a direct correlation to declining forest health.

• Positive Impacts
• research and education

Economic Importance for Humans: Negative

There are no known negative effects of brown-headed nuthatches on humans.

Conservation Status

Brown-headed nuthatches are currently listed as "least concern" on the IUCN Red list and of "no special status" on the CITES appendices. Brown-headed nuthatches are facing habitat losses especially in Georgia, Florida and South Carolina due to clear-cutting, logging and forest fragmentation, as well as fire suppression. Brown-headed nuthatches require regular prescribed burns to keep the understory clear and without them, these birds will leave the territory for somewhere more suitable.

Additional Links

Encyclopedia of Life

BioKIDS Critter Catalog

Contributors

Nikohl Miller (author), Radford University, Karen Powers (editor), Radford University, Leila Siciliano Martina (editor), Texas State University.

References

Barbour, B., A. DeGange. 1982. Reciprocal allopreening in the brown-headed nuthatch. The Auk , 99/1: 171.

Collins, W., G. Jeffery, J. Skinner, A. Harrison, F. Arnold. 1966. Blood parasites of birds at Wateree, South Carolina. The Journal of Parasitology , 52/4: 671-673.

Cox, J., G. Slater. 2007. Cooperative breeding in the brown-headed nuthatch. Wilson Journal of Ornithology , 119/1: 1-8.

Cox, J. 2012. Social grooming in the Brown-headed Nuthatch may have expanded functions. Southeastern Naturalist , 11/4: 771-774.

Dornak, L., B. Burt, D. Coble, R. Conner. 2004. Relationships between habitat and snag characteristics and the reproductive success of the brown-headed nuthatch ( Sitta pusilla ) in eastern Texas. Southeastern Naturalist , 3/4: 683-694.

Haney, J. 1981. The distribution and life history of the brown-headed nuthatch ( Sitta pusilla ) in Tennessee. The Migrant , 52/4: 77-86. Accessed July 11, 2013 at http://www.tnbirds.org/MigrantOnline/V052/V052077-086.pdf .

Herb Jr, A., B. Burt. 2000. Influence of habitat use-patterns on cooperative breeding in the brown-headed nuthatch. Texas Ornithological Society , 33/3: 25-36.

Lloyd, J., G. Slater, S. Snow. 2009. Demography of reintroduced eastern bluebirds and brown-headed nuthatches. Journal of Wildlife Management , 73/6: 955-964.

Lloyd, J., G. Slater. 2007. Environmental factors affecting productivity of brown-headed nuthatches. The Journal of Wildlife Management , 71/6: 1968-1975.

Love, G., S. Wilkin, M. Goodwin. 1953. Incidence of blood parasites in birds collected in southwestern Georgia. The Journal of Parasitology , 39/1: 52-57.

Morse, D. 1967. Foraging relationships of Brown-Headed Nuthatches and Pine Warblers. Ecology , 48/1: 94-103.

Morse, D. 1968. The use of tools by brown-headed nuthatches. The Wilson Bulletin , 80/2: 220-224.

Pennock, C. 1890. Notes on breeding habits of brown-headed nuthatch at Thomasville, Georgia. The Ornithologists' and Oologists' Semi-Annual , 2/1: 29-31.

Phillips, T. 2002. Brown-headed nuthatch. Birdscope , 16/2: None. Accessed July 09, 2013 at http://www.birds.cornell.edu/Publications/Birdscope/Spring2002/nuthatch.html .

Sherman, I. 1979. Biochemistry of plasmodium (malarial parasites). Microbiological Reviews , 43/4: 453.

Slater, G. 2001. "Avian Restoration in Everglades National Park (1997-2001): Translocation, Methodology, Population, Demography, and Evaluating Success" (On-line pdf). Accessed November 29, 2013 at http://www.ecoinst.org/files/Slater_2001_Avian_restoration_PhaseII_Final.pdf .

Stanton, R. 2013. "Habitat selection of brown-headed nuthatches at multiple spatial scales" (On-line pdf). Accessed December 17, 2013 at https://mospace.umsystem.edu/xmlui/bitstream/handle/10355/38390/research.pdf?sequence=2 .

Tacutu, R., T. Craig, A. Budovsky, D. Wuttke, G. Lehmann, D. Taranukha, V. Costa Fraifeld, J. de Magalhaes, V. Fraifeld, J. de Magalhaes. 2012. "AnAge entry for Sitta pusilla " (On-line). Human Ageing Genomic Resources. Accessed July 07, 2013 at http://genomics.senescence.info/species/entry.php?species=Sitta_pusilla .

Wehr, E., J. Hwang. 1957. Oxyspirura (Yorkeispirura) pusillae n. sp. ( Nematoda : Thelaziidae ) from the orbital cavity of the brown-headed nuthatch, Sitta pusilla Latham, 1790. The Journal of Parasitology , 43/4: 436-439.

Wilson, M., B. Watts. 1999. Response of brown-headed nuthatches to thinning of pine plantations. The Wilson Bulletin , 111/1: 56-60.

Withgott, J., K. Smith, G. Slater, J. Lloyd. 2013. Brown-headed nuthatch ( Sitta pusilla ). The Bird of North America , 349: None. Accessed August 16, 2013 at http://bna.birds.cornell.edu/bna/species/349/articles/introduction .