The corncrake had been struggling to hold on in the UK
The number of corncrakes in Scotland is estimated to have fallen for the first time in a decade, it has been warned.
RSPB Scotland said the population of calling males had dropped by about 8%, from 1,236 in 2007 to 1,140 this year.
The drop comes despite a successful programme to boost numbers which has seen them steadily rising since 1998.
The migratory birds have strongholds in the Hebridean and Argyll islands, where the vast majority of the UK population can be found.
A recovery programme was launched in 1993 in an attempt to increase the corncrake population in their Scottish areas.
The fall in number this year represents only the second such drop since the start of the initiative.
The programme was launched in response to the disappearance of the birds' natural habitat from the mainland, tall grass and herbs, and involves the cultivation of hay meadows and field margins.
The RSPB said this year's decrease was a warning that there was no room for complacency.
Paul Walton, RSPB Scotland species policy officer, said: "The decline we've seen this year is worrying and should serve as a warning to the Scottish Government that if we want to preserve these great wee birds then we need to ensure that there are sufficient funds available for targeted agri-environment options such as those that benefit corncrake.
"The new rural priority scheme includes all the right ingredients. We must now work on ensuring good applications are being put forward and accepted."
Corncrakes, with their distinctive rasping call, live on dry land and are secretive birds, spending much of their time hiding in tall vegetation.
They migrate to Scotland in late spring from sub-Saharan Africa.
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