The buff-bellied pipit or American pipit (Anthus rubescens) is a small songbird found on both sides of the northern Pacific. It was first described by Marmaduke Tunstall in his 1771 Ornithologia Britannica. It was formerly classified as a form of the water pipit. It is known as "American pipit" in North America and "buff-bellied pipit" in Eurasia.
Description
Like most other pipits, the buff-bellied pipit is an undistinguished-looking species which usually can be seen to run around on the ground. The rubescens subspecies (or American pipit) has lightly streaked grey-brown upperparts and is diffusely streaked below on the buff breast and flanks. The belly is whitish, the bill and legs are dark. The japonicus subspecies (or Japanese pipit) is darker above and has bolder black streaking on its whiter underparts; its legs have a reddish hue. The call is a squeaky sip.
Measurements:
Length: 16 cm
Weight: 22 g
Wingspan: 24 cm
Taxonomy
The scientific name is from Latin. Anthus is the name for a small bird of grasslands, and the specific rubescens means "reddish", from ruber, "ruddy".
Four subspecies are currently recognized belonging to two main groups. Morphological and DNA sequence differences between them are rather pronounced and they might be considered distinct species pending further research: A. r. rubescens - (Tunstall, 1771), – breeds in northern Canada east to Greenland and northeast United States, wintering in Central America A. r. pacificus - (Todd, 1935) Breeds in Pacific Cordillera from Alaska to Oregon, wintering in western Mexico. Birds breeding in south Alaska have sometimes been recognized as a distinct subspecies A. r. geophilus. A. r. alticola - (Todd, 1935) Breeds in the Rocky Mountains from southern British Columbia to California, wintering in Mexico A. r. japonicus - Temminck & Schlegel, 1847, or Siberian pipit – breeds in most of the eastern Palearctic (including Japan)
This species is closely related to European rock pipit (A. petrosus) and water pipit (A. spinoletta), all three forms having previously been considered conspecific. They can be differentiated by their vocalizations and some visual cues, but rock and buff-bellied pipit are not found sympatrically except as vagrant individuals, and the ranges of buff-bellied and water pipits overlap only in a small area in Central Asia.
Behavior
Both subspecies of the buff-bellied pipit are migratory. The buff-bellied pipit winters on the Pacific coast of North America, and on the Atlantic coast from the southern North America to Central America. At least regarding the buff-bellied pipit, its wintering range seems to have expanded northwards in the 20th century and the birds seem to spend less time in winter quarters: in northern Ohio, for example, the species was recorded as "not common" during migration in May and September/October in the 1900s (decade), but today it is considered a "widespread migrant" in that region, found between March and May and from late September to November, with many birds actually wintering this far north. Asian birds winter mainly from Pakistan east to and Southeast Asia, with occasional birds found as far north as Yunnan and some in Japan apparently being all-year residents or migrating but a little. The American and Asian subspecies are rare vagrants to Western and Eastern Europe, respectively.
Like its relatives, this species is insectivorous. The breeding habitat of buff-bellied pipit is tundra, but outside the breeding season it is found in open lightly vegetated areas, similar to those favoured by the water pipit (A. spinoletta).