Bewick's swans (Cygnus columbianus bewikii) are the smallest of the three types of swan found in Britain. Usually, they mate for life and the pairs spend each summer at nesting and nursing sites in northern Russia. Then, in September/October, with the Arctic winter beginning, large groups of families start moving in stages across north western Europe, seeking warmer weather.
Many settle in the Netherlands but, traditionally, around 3,000 - 5,000 travel on to Britain, to overwinter around the rivers Ouse (WWT Welney, Norfolk), Ribble (WWT Martin Mere, Lancashire) and Severn (WWT Slimbridge, Gloucestershire). A unique bill recognition system means WWT is able to identify many of the visitors by name and knows their full family history, sometimes stretching back 20 years or more.
Bewick's swans make early arrival bringing winter to WWT Slimbridge
October 2010. The first Bewick's swans of the season have arrived at WWT Slimbridge Wetland Centre in Gloucestershire, heralding the start of winter - and it may mean that it could be even colder than last winter.
Staff opening up the Centre on October 18th saw the eight swans on the Rushy Lake at dawn. It is the earliest they have arrived since 2003, when they also arrived on the 18th. A couple of the swans called Riso and Risa are among these first returning Bewick's; Risa has been coming here for 13 years.
Arrived with last years 5 chicks
They arrived with five yearlings which were last year's juveniles. These weren't named last year as their unique bill pattern, which they are identified from, takes time to form. The eighth Bewick's to arrive is still waiting to be identified.
No comments:
Post a Comment