Brown creeper

The brown creeper (Certhia americana), also known as the American treecreeper, is a small songbird, the only North American member of the treecreeper family Certhiidae.

Adults are brown on the upper parts with light spotting, resembling a piece of tree bark, with white underparts. They have a long thin bill with a slight downward curve and a long stiff tail used for support as the bird creeps upwards. The male creeper has a slightly larger bill than the female. Brown creepers are smaller than white-breasted nuthatches but larger than golden-crowned kinglets.

Measurements:

Length: 4.7–5.5 in (12–14 cm)

Weight: 0.2–0.3 oz (5.7–8.5 g)

Wingspan: 6.7–7.9 in (17–20 cm)

Its voice includes single very high pitched, short, often insistent, piercing calls; see, or swee. The song often has a cadence like; pee pee willow wee or see tidle swee, with notes similar to the calls. Creepers in California have songs of four to nine syllables, except in the San Bernardino Mountains, where there are as many as nine to thirteen syllables per song, but within the same two second time frame.

This species's avoidance of edges, cryptic plumage, and high-pitched vocalizations contribute to a low survey detection rate compared to other species.