Breeds in mature forests, typically spruce and/or fir, or where spruce or fir are mixed with hardwoods (Hamel 1992). Occasionally breeds in hemlock or white pine forests (Hamel 1992, Simpson 1992). Forages on the trunk and limbs of trees (Kaufman 1996).

Nest is commonly built behind bark scales (Potter et al 1980) or a loose piece (Hamel 1992) / large strip (Kaufman 1996) of bark still attached to the tree. Ehrlich et al (1988) describe it as a 'hammocklike cup.' Knotholes and natural cavities are also known as nest placement locations (Potter et al 1980). On average nest is usually 5 to 15 feet above the ground (Harrison 1975). Potter et al (1980) lists material such as moss, lichens, rootlets, grasses, spider cocoons, and shredded bark as material used for construction of the nest. Creepers forage up the bark of trees, starting at the base, searching the crevices for small insects, larvae, and insect eggs (Hamel 1992).

NATURE SERVE GLOBAL HABITAT COMMENTS:

Preferred habitat includes forest, woodlands, forested floodplains and swamps. Scrub and parks are also used in winter and during migration. Brown creepers are most often found in coniferous and mixed forests. A study by Franzreb (1985) describes the habitat in Arizona as mixed-coniferous forest, dominated by Douglas-fir, ponderosa pine and southwestern white pine. Within they're habitat, birds selected the largest (tallest) trees most often for foraging. Hejl (1992) reported finding larger numbers in western red cedar stands than in the Douglas-fir/ponderosa pine stands in 1992 field work.

In the eastern U.S. south of the northern conifer zone, populations occur regularly in forested floodplains, and sometimes swamps. Hamas (1992), based on his experience, suggested that floodplain forests may be important habitat in Michigan. Davis (1978) studied populations in Michigan in two different forest types. One was an old white cedar, balsam fir, and black spruce swamp, with components of sugar maple, red maple, white pine, basswood and paper birch. The other was more topographically varied and drier; tree species included red maple, American beech, with less common white oak, eastern hemlock, large-toothed aspen, butternut hickory, and American elm. In the wetter areas of this site, dead American elms were common, and in the wettest areas, white cedar and eastern hemlock occurred. Davis (1978) found that all nests were in dead trees, and all nest trees were near water. Two were in swamps, while all others were within 60 m of flowing streams.

A component of dead trees is essential for nesting, so brown creepers tend to be associated with older forests. Hejl and Woods (1991) found them in old growth forests (200+ yr), but never in rotation-aged (80 to 120 yr) Douglas- fir/ponderosa pine stands in western Montana and adjacent Idaho. The birds have also been known to move into areas where many trees have died due to flooding or disease (Bent 1964).