Changing landscapes blamed for halving bird populations

Published on 16/02/2011 15:03

THE mysterious decline in the populations of upland wading birds cannot be attributed to any one factor but is due to a range of land management changes, conservationists have concluded following the first major investigation into the issue.

RSPB Scotland said that a drop of up to 50 per cent in the numbers of lapwing, dunlin and curlew in the uplands over the last 25 years was caused by a combination of changes in habitat, including forest edge exposure, grouse moor management intensity and an increase in the population of crows. Numbers of golden plover and snipe have also dropped.

But experts warned that the decline of the birds - once a common sight on farmland and uplands and praised in many well-known works of literature for their evocative calls - needed further research.

The charity, working with Scottish Natural Heritage, analysed changes in the abundance of waders from almost 1,500sq km across the UK's uplands - including the islands of Lewis and Harris and areas of north-east Scotland - examining whether population changes could be linked to variations in land use.

"This research shows the complex nature of changes in our wader populations in the uplands, including vividly revealing the decline in curlew and lapwing numbers," said Professor Des Thompson of SNH.

"Many people working in the uplands lament the loss of these birds, so we do need to intensify our understanding of what is happening, and then try to do something about it."

The results of the survey, published in the international scientific journal Bird Study, found that numbers of golden plover and snipe declined more in upland landscapes where there was more forestry in surrounding areas, while declines in lapwing numbers were greatest in areas dominated by heather.

Lapwing populations fared better on areas with more intensive grouse moor management and worse where there was high crow numbers.

The same was not true, however, for golden plover - which suffered its greatest declines in areas where grouse moor management was more intensive.

Dr Murray Grant, a principal conservation scientist with RSPB, said: "The decline of uplands waders has been a cause for concern for years, particularly as the reasons for these changes were not clear-cut. These are birds that were commonplace three or four decades ago."

He added: "This new research provides useful indicators on which factors might be important in driving declines in these splendid birds."The next task will be to use this information to dig a little deeper and determine the mechanisms for the declines and what we can do to help these species in areas where decreases are greatest."

Lapwing: Also known as the peewit in imitation of its display calls, its Latin name - vanellus vanellus - describes its wavering flight. The species breeds largely on farmland, especially among crops sown in spring which are adjacent to grass and bare land. Also on pasture, wet grassland and marshes.

Golden plover: a distinctive gold and black summer plumage. In winter the black is replaced by buff and white. They typically stand upright and run in short bursts. In winter, when they move to lowland ground, they form large flocks which fly in tight formation.

Dunlin: The most common small wader found along the coast. It has a slightly downcurved bill and a distinctive black belly patch in breeding plumage. It feeds in flocks in winter, roosting on nearby fields, saltmarshes and shore when the tide is high.

Snipe: Snipe are medium-sized, skulking wading birds with short legs and long straight bills. During the breeding season snipe are most often spotted on moorland, especially on early spring mornings, when males can be heard giving their "drumming" or "bleating" display.

Curlew: The curlew is the largest European wading bird, instantly recognisable on winter estuaries or summer moors with its long downcurved bill, brown upperparts and long legs. The largest populations in the UK are found in a handful of areas including the Solway Firth. They are also seen in the southern uplands and east Highlands of Scotland.