Whitehead's spiderhunter

Whitehead's spiderhunter (Arachnothera juliae) is a species of spiderhunter in the sunbird and spiderhunter family Nectariniidae. It is endemic to Borneo, where it is found in the mountain ranges in the north-central part of the island. It inhabits hill dipterocarp forest, primary and secondary montane forest, and forest edge at elevations of 930–3,000 m (3,050–9,840 ft). A large and distinctive spiderhunter, the species is mostly brown with profuse whitish streaking all over the body and bright yellow vents and uppertail coverts. Both sexes are similar in appearance, but males are larger, with a length of 16.5–18 cm (6.5–7.1 in) compared to a length of 15.5–16.5 cm (6.1–6.5 in) for females. The juvenile plumage is unknown.

The species feeds on small arthropods, berries, and nectar, foraging alone, in pairs, or in small flocks of up to five birds. It breeds from March to at least August, making bark-lined nests in hollows it excavates in naturally occurring clumps of moss, vegetation, and roots. This nest is unique within its genus and is shared only with the closely related yellow-eared and naked-faced spiderhunters. Clutches consist of two chicks, which are fed berries and arthropods. It is listed as being of least concern by the International Union for Conservation of Nature, but is experiencing a population decline caused by habitat destruction.

The species is a large, distinctive spiderhunter, with males having a length of 16.5–18 cm (6.5–7.1 in) and females having a length of 15.5–16.5 cm (6.1–6.5 in). It is mainly brown with profuse streaking on the head and body, buffy white streaking on the top of the head, narrow white streaks on the neck and back, fine brownish-white streaking on the throat, and broad white streaking on the rest of the underparts. The vent and uppertail coverts are bright yellow. The iris is brown, while the legs and bill are black. Both sexes look similar, while the juvenile plumage is unknown.

Whitehead's spiderhunters have very distinctive vocalisations, with a high-pitched, squeaky song. Their calls include a wheezy wee-chit, with the first note rising and second note falling in pitch, a complex series of nasal and wheezy wit-wit-wit-wt'wt'wt'weehee twitters and trills, and a teeh-teeh-wee, with the wee rising in pitch. Other calls are a see-wee see-wee, a swee-eee-eee, a tee-tee-swee-ee, prolonged twittering, and loud shrieks made in flight or while perched.