New Zealand plant 'choking' loch near Nairn
Rare wildlife has been threatened by a non-native aquatic plant choking out native species, Scottish Natural Heritage (SNH) has said.
New Zealand pigmyweed has spread to form dense mats over the waters of Loch Flemington, near Nairn.
The shallow, glacial loch provides habitat for colourful Slavonian grebe.
Volunteers have been covering over large areas of the weed to starve it of sunlight and kill it. The method has been used on lochs in West Galloway.
The British Trust for Conservation Volunteers have been working on the SNH-led project.
SNH said the spread of pigmyweed may be a factor behind Slavonian grebe not breeding at the loch since 2001.
Last year, RSPB Scotland said protecting habitats in Scotland was "critically important" to conserving the grebes and other threatened UK bird species.