A moulting population of non-breeding Mute Swans with special reference to flight-feather moult, feeding ecology and habitat selection

摘要: The build-up of the moulting numbers at ground and their decline followed a regular, gradual curve. This implies clear time relation between arrival departure. Individual swans started to moult about 30 days after arrival, this span reducing half later part influx period. Governing factors must include population density, available food supplies hormonal condition. Males start somewhat prior females. regained ability fly 3-4 weeks before flight feathers achieved full length. rate departure seems be dependent on density supplies. shifted haunts in changed main was Zostera during summer early autumn, while Ulva taken later. totally eliminated certain areas. consumed 425 metric tons, mainly Zostera, but also some Ulva.