Habitat use, moult and biometrics in the manchurian reed warbler acrocephalus tangorum wintering in Thailand

Abstract

Manchurian Reed Warblers Acrocephalus tangorum wintering at Khao Sam Roi Yot, Thailand, were largely restricted to mature Phragmites reeds. The mean wing length (± sd) of 105 Manchurian Reed Warblers was 54.5 ± 1.41 mm. There was no evidence of differences in body weight in spring, autumn or winter. Both adults and first-winter birds underwent a complete moult soon after arrival in their winter quarters. Primary moult duration was estimated to be 59 days. Moult of secondaries was suspended in approximately one-third to one-fifth of birds, the few retained, old, unmoulted feathers usually being replaced later in the winter. No further moult was usually detected prior to northward spring migration. © 2003 British Trust for Ornithology.