Physical characteristics

The members of this family are small birds. Pipits and wagtails are structurally very similar, having a slim, elongated body, a small rounded head and short neck, a slender pointed bill with rictal bristles, a medium to long tail (longest in the wagtails and shortest in pipits associated with trees), rather long legs and toes and, especially in pipits, a long hind claw. The wings have 10 primaries, the outermost being vestigial, and in most species the tertials (top feathers) are long, often reaching to the tips of the primaries in the folded wing. The wing formula is useful in identifying some pipits. The long-claws are larger and more robust, with relatively short tails and very long, curved hind claws that can reach 1.25 in (mean 0.8 in; 32 mm, mean 21 mm) in the yellow-throated longclaw (Macronyx croceus) and facilitate walking and perching on grass clumps. Wagtails have a horizontal stance on the ground and a more upright stance when perched, pipits usually have a less horizontal stance, and longclaws are even more upright, often having a lark-like appearance.

Wagtails are strikingly colored or patterned, at least in adult plumage, with black, white, gray, yellow, or green. Young birds and nonbreeding plumages are generally less conspicuous. The males and females of most species differ to

A South Georgia pipit (Anthus antarcticus) perches near the water. (Photo by G. Lasley/VIREO. Reproduced by permission.)

some extent in plumage. Most species have pale wing-bars or white wing-panels, the tertials have prominent pale outer edges and the tail is edged with white. Variation in the yellow wagtail (Motacilla flava) is complex, with up to 15 morphological types, which may be morphs, intergrading subspecies or sympatric species (those that occupy the same area but maintain their own identity).

Pipits are cryptically colored and patterned, usually having brown upperparts and whitish underparts, with dark streaking, although some species are almost unstreaked. The tail is edged with white, buff, or pale brown, the color and pattern being important in identification. In most species the sexes are identical in plumage and there is little or no seasonal variation. Many species are very similar in appearance and are very hard to identify, although vocalizations are usually diagnostic. The olive-backed pipit (Anthus hodgsoni) is unique with its greenish upperparts and white underparts beautifully decorated with lines of large black spots on the breast and flanks. Some pipits have brighter colors in the breeding plumage, with red or pink on the throat and breast in rosy pipits (A. roseatus) and red-throated pipits (A. cervi-nus), and yellow underparts on the yellow-breasted pipit. The golden pipit is peculiar because the lower part of the tibia is not feathered and the sexes are very distinct, the male being very brightly colored.

Longclaws have cryptically patterned upperparts and brightly colored underparts. Adults have a blackish or strongly dark-streaked "necklace" bordering a yellow, orange, or red chin and throat. This color extends to the rear underparts in some species. The tail has white corners. Young birds have a less distinct necklace and duller underparts. The yellow-throated longclaw is the ecological equivalent of the American meadowlark (Sturnella neglecta), which it resembles very closely in plumageā€”a striking example of convergence.

0 0

Post a comment