Reproductive biology

Courtship displays are given by some species. The mountain wagtail, which pairs permanently and defends a permanent territory, indulges in erratic aerial chases and an aerial "spiral dance." Other wagtails also pair monogamously and permanently, and the male cape wagtail displays by presenting the female with nesting material throughout the year. Carrying and presenting nesting material is also recorded in Berthelot's pipit (Anthus berthelotii) and other pipit species, while courtship feeding is practiced by wagtails and pipits. Breeding pipits perform aerial courtship chases, which sometimes precede copulation. Breeding pairs of Sharpe's longclaw (Macronyx sharpei) perform fluttering or circular flights together over the territory.

Pipits nest on the ground, often in grass. The red-throated pipit sometimes builds at the end of a short tunnel in a mossy hummock. Wagtails may also nest on the ground, in grass or reeds, on flood debris or below bushes, but they commonly nest in crevices or holes in rocks, cliffs, stream banks, and walls, under bridges, and in tree roots and hollow branches; the white wagtail sometimes uses old nests of other species. Longclaw nests are hidden in, or at the base of, a grass tussock or among herbaceous plants.

Nests are cup-shaped, sometimes placed in a depression or a shallow scrape, are usually neatly built of grass, stems, rootlets, twigs, or moss and are often lined with hair, wool, feathers, or plant fibers. The female builds, usually with the male in attendance and, in some species, with the help of the male.

Egg colors vary from white, cream, buff, or gray to (in pipits) olive, reddish, or dark brown, spotted or blotched (in wagtails sometimes also streaked) with brown, gray, mauve, purple, or black. Longclaws and the tree pipit sometimes lay pale blue, pink, or green eggs. The clutch size of wagtails is three to eight (usually four to six) in higher latitudes and one to seven (usually two to four) at lower latitudes; pipits lay two to nine (usually four to six) eggs at higher latitudes and only two to four (usually three) in the tropics. Longclaws lay two to five eggs, most commonly two or three. Incubation is usually by the female only, but by both sexes in some species; it takes 11-16 days. Both parents usually care for the young, which fledge after 10-17 days (exceptionally 19-20 days in the cape wagtail). Young often leave the nest before they are fully fledged and able to fly.

In temperate latitudes, wagtails and pipits breed from April to August (mostly April through June), but Berthelot's pipit has an extended season, from January to August. In the tropics, pipits and wagtails breed mainly at the end of the dry season and during the rains. Longclaws and the golden pipit breed during or just after the rains, the development of grass cover for nest concealment probably being an important factor in the timing of breeding. Some pipits and wagtails breed two or three times per year, including the African pied wagtail, which may sometimes breed continually throughout the year. High-latitude species are usually single-brooded because the breeding season is short.

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