Thermal image of birds
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String sparrowhawk tests birds' stress levels

Scientists from Glasgow University are using thermal imaging cameras to gain a remarkable insight into the lives of Scotland's birds.

Their work is designed to find a new way of measuring stress in the natural world.

A sparrowhawk on a string has a key role.

BBC Scotland's environment correspondent David Miller travelled to the shores of Loch Lomond to find out more about the project.