Hainan Leaf Warbler Phylloscopus hainanus

Beautifully luminous small leaf warbler restricted to the forests of China’s Hainan Island. Bright yellow all over, though darker wings and crown make paler wingbars and eyebrow visible nonetheless. Fairly distinctive in its limited range; Hartert’s Leaf Warbler also has a yellow cast but is duller overall and much larger, with a much more elongated appearance. Song is a short jumble of squeaky high-pitched notes akin to a machine that needs oiling.