Swans at dusk at Linlithgow, ScotlandWith the birds front lit against a darkening sky, this photograph of swans at Linlithgow in Scotland may look like a glorious nature scene, but the reality behind it is a little different. On the day it was taken 6 April 2006 bird flu was found in a dead swan in Cellardyke, a coastal village about 10 miles south of St Andrews, Fife. The bird had the dubious honour of being the first wild bird in Britain to be found with the deadly H5N1 strain of the