Kloss's leaf warbler is a leaf warbler found in Cambodia, China, Laos, Thailand, and Vietnam. Its natural habitats are temperate forests, subtropical or tropical moist lowland forests, and subtropical or tropical moist montane forests.
Region
Southeast Asia and southern China
Typical Environment
Occurs in Cambodia, China (southern regions), Laos, Thailand, and Vietnam. It inhabits temperate forest at higher elevations as well as subtropical and tropical moist lowland and montane forests. The species uses forest edges, secondary growth, bamboo thickets, and riparian corridors where cover is dense. It forages from the understory up to the mid-canopy and may move locally along elevational gradients.
Altitude Range
0–2500 m
Climate Zone
Tropical
Ease of Keeping
Beginner friendly: 1/5
A small, active leaf warbler of Southeast Asian forests, it often joins mixed-species flocks and forages restlessly in the understory to mid-canopy. Identification relies heavily on voice because its plumage is similar to other Phylloscopus warblers. It was historically confused within a complex of cryptic leaf warblers and is best located by its high, thin, repeated notes.
Temperament
active and somewhat skulking
Flight Pattern
short rapid wingbeats
Social Behavior
Typically seen singly or in pairs during the breeding season and more loosely gregarious in mixed-species flocks outside it. Nests are cup-like and placed low in dense vegetation or near the ground. Both sexes participate in territorial defense through song and calls.
Migratory Pattern
Partial migrant
Song Description
Song and calls are high-pitched, thin, and sibilant, often a series of sharp see-see or tsi notes and brief trills. Vocalizations are key for separation from similar leaf warblers and carry well through dense foliage.
Plumage
Olive-green upperparts with pale whitish to yellowish underparts and a clean, contrasting face. Shows a distinct pale supercilium and a darker eye-stripe; wingbars are faint to weakly defined. Feathers are fine-textured and smooth, suited to a sleek, compact appearance typical of leaf warblers.
Diet
Feeds mainly on small insects and other arthropods, including caterpillars, beetles, and spiders. It gleans prey from leaves and twigs, occasionally hovering to pick items from the underside of foliage. Short sallies to snatch flying insects are also performed when opportunities arise.
Preferred Environment
Forages in the understory to mid-canopy of moist forests, along edges, and in secondary growth. Frequently works through vine tangles, bamboo, and dense shrubs where insect prey is abundant.
