In winter the British Isles is host to millions of ducks, geese and swans, which gather on coastal estuaries and mudflats. In London Bill watches birds in his own back garden and then takes a trip to Brent reservoir, an oasis for our feathered friends amidst the urban sprawl of outer London. On Islay, off the west coast of Scotland, Bill tracks down the rare and comical chough, finds out where London pigeons come from and watches vast flocks of wild geese as they fill the sky with their haunting cries. Show less