Lemon-rumped warbler
The Lemon-rumped Warbler (Phylloscopus chloronotus), also known as the Pale-rumpedTemplate:Speciesbox
Warbler, is a small species of Old World warbler in the family Phylloscopidae.<ref name="BOW">"Lemon-rumped Warbler (Phylloscopus chloronotus)". Birds of the World. Cornell Lab of Ornithology. Retrieved 13 October 2025.</ref> It is native to the Himalayas, breeding in montane forests and wintering in the southern foothills and the Purvanchal Range.<ref name="eBird">"Lemon-rumped Warbler – Species Map". eBird. Cornell Lab of Ornithology. Retrieved 13 October 2025.</ref> The species is structurally identical to the Sichuan Leaf Warbler (Phylloscopus forresti), but differs in vocalizations.<ref name="Avibase">"Phylloscopus chloronotus – Avibase". Avibase – the World Bird Database. Bird Studies Canada / BirdLife International. Retrieved 13 October 2025.</ref>
Taxonomy
The Lemon-rumped Warbler was once grouped with the Sichuan Leaf Warbler (Phylloscopus forresti) and was previously classified within P. proregulus. Vocal and genetic studies confirmed its separation as a distinct species.<ref name="Avibase" /> Related taxa in China, including P. kansuensis and P. yunnanensis, are also now recognized as separate.<ref name="BOW" />
Description
The Lemon-rumped Warbler is 9–10 cm long and weighs about 4.6–5.1 g.<ref name="BOW" /> It has a whitish crown stripe bordered by darker olive-brown sides, a pale line above the eye, and a dark eyestripe that often curves downward. The upperparts are greenish-grey, and the rump is yellowish or whitish, which gives the species its name. The wings are grey-brown with green edging and usually show one or two pale wingbars. The underparts are whitish or buff with some grey along the breast sides. The bill is dark with a yellowish or orange base to the lower mandible, and the legs are dark grey.<ref name="BOW" /> Males and females are similar, though females are slightly smaller. Juveniles resemble adults. Two subspecies are recognized: one in the central and eastern Himalayas and another in the west, which shows greener and more buff-toned plumage.<ref name="BOW" />
Distribution and habitat
The species breeds across the Himalayas from northern Pakistan through Nepal into India, Bhutan, and China.<ref name="eBird" /> In winter, it descends to lower elevations, reaching Assam and occasionally Myanmar, though its presence in Afghanistan is uncertain.<ref name="eBird" /> It inhabits montane forests between 2 200 and 4 200 meters above sea level. In Pakistan it is most frequent at elevations of 2 200–2 700 m, while in Nepal it ranges up to 4 000 m. Winter records occur from 300–2 700 m, generally above 1 000 m. Breeding habitat includes spruce and fir forests with rhododendron and broadleaf trees, as well as oak and lower-elevation broadleaf stands near the conifer zone.<ref name="BOW" />
Behavior
Movements
The species makes altitudinal movements, breeding higher in summer and descending to lower elevations in winter.<ref name="eBird" />
Feeding
Its diet consists mainly of insects and larvae. It forages alone or in pairs in winter but also joins mixed-species flocks. Foraging occurs in the canopy and understory, often involving short hovering or sallies to catch prey in the air—a behavior known as flycatching.<ref name="BOW" />
Vocalizations
Two song types are reported: a short trill followed by a lower trill lasting 2–4 seconds, and a longer, varied series of notes that may last several minutes. The call is a sharp, high “pist” or “psit.”<ref name="Avibase" />
Breeding
Breeding occurs from April to July, with the majority of activity taking place in May and June. The nest is a ball-shaped structure with a side entrance, built by the female from grass, moss, lichen, and birch bark, and lined with feathers. Nests are placed 2–15 m above the ground, usually in conifers. Clutches contain 3–5 eggs, most often four. The female incubates the eggs, and both adults feed the young.<ref name="BOW" />
Conservation
The Lemon-rumped Warbler is assessed as Least Concern on the IUCN Red List.<ref name="IUCN">"Phylloscopus chloronotus". IUCN Red List of Threatened Species. International Union for Conservation of Nature. Retrieved 13 October 2025.</ref> It is widespread across the Himalayas with stable populations. Much of its range lies within protected areas, and no major threats are currently reported.<ref name="IUCN" /> Localized logging or habitat alteration may affect populations, but the species is able to adapt to a range of montane forests.<ref name="IUCN" />