BLACK grouse, curlews and other upland birds have suffered a decline in numbers as woodland and farmland species increase, a report shows.

Scottish Natural Heritage (SNH) found upland varieties were more at-risk than others, with populations of ten of the 17 types plummeting over the last two decades. An overall fall of 16 per cent was recorded.

Drops of more than 40 per cent were noted for the black grouse, curlew, dotterel and golden plover. All are the subject of conservation efforts, including extensive peatland restoration to tackle habitat problems.

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Meanwhile, fortunes have improved for woodland species, which increased by almost 70 per cent from 1994-2016, and farmland birds went up by 13 per cent.

The great-spotted woodpecker is amongst the biggest winners, which SNH has linked to an overall trend for Europe, thought to be the result of greater connection between wooded areas.

For farmland species, goldfinches have increased to become “a common site” and the whitethroat has recovered from historical lows associated with droughts in its African overwintering grounds.

Simon Foster of SNH said: “It’s wonderful to see that woodland and farmland birds are not only holding their own in Scotland, but that many are thriving.

“However, with some upland birds struggling, there are a lot of people and projects working hard to improve conditions for waders – some of which have seen worrying declines. We and many of our partners are hoping to see these birds fare better in the coming years.”

The data was collected with the help of volunteers through the British Trust for Ornithology (BTO) and Joint Nature Conservation Committee.

BTO Scotland head Dr Chris Wernham said: “The Scottish uplands cover a vast area and are a key part of the country’s landscape.

“Monitoring our upland bird populations presents a unique set of challenges – these are remote, often inaccessible areas, many miles from human population centres.

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“It is thanks to the effort and dedication of intrepid volunteers that we are able to produce this report, which highlights worrying declines among a suite of upland bird species, contrasting with increases in many woodland birds.

“Through initiatives within the Breeding Bird Survey such as Upland Rovers we hope to see continued improvements in coverage, enabling greater precision in our estimates of change, and in time allowing us to report trends for a greater number of species.”