Chasing Britain's most threatened duck
A team from the Wildfowl and Wetlands Trust (WWT) is capturing and tagging female common scoters, to find out why these birds are in such severe decline in Britain.
Just 35 pairs of the birds now breed in the UK each year, most of them by lochs in the highlands of Scotland.
The ducks are one of the few British bird species about which very little is known.
Their nests are well hidden across some of the most remote landscapes in Britain, making them difficult to find and to study.
But WWT researcher Ed Burrell is spending the summer in a secret location in the highlands to monitor, catch and tag the beleaguered birds.
Video journalist: Victoria Gill