Modern practices push farmland birds to brink of extinction

 

The Atlasproject is the most comprehensive survey on bird life in more than two decades

PREVIOUSLY COMMON farmland birds such as the corncrake, curlew and yellowhammer are now perilously close to extinction in Ireland, according to a four-year study of the island’s bird populations.

Preliminary data from the Bird Atlas 2007-2011survey, which concludes at the end of the month, also indicate an alarming fall-off in summer migrants such as the cuckoo, combined with a sharp rise in buzzard numbers and the re-emergence of woodpeckers after centuries of absence.

The Atlasproject, which aims to map all of Ireland and Britain’s 578 bird species, is the most comprehensive survey of bird life undertaken on these islands in more than two decades and will inform conservation policy for decades to come.

Crucially for ornithologists, it provides the clearest picture yet of how bird populations in Ireland, in terms of density and diversity, are being affected by climate change and more intensive farming practices.

The survey, which is being jointly co-ordinated by BirdWatch Ireland, the British Trust for Ornithology and the Scottish Ornithologists Club, highlights a remarkable decline in some of Ireland’s most emblematic farmland birds, such as the corncrake and the curlew.

The corncrake, whose distinctive cry used to be the bane of sleepless farmers, has seen its breeding population plummet by more than 80 per cent in the past 20 years alone.

The birds, which were breeding in every county in Ireland until the 1970s, have been a victim of the move from traditional hay-cutting to silage production, which has wiped out their traditional hay-meadow habitat.

Breeding populations of curlew are following a similar trajectory, down 60 per cent, as a result of the drive to reclaim more of the Republic’s wetlands for agriculture.

Other waders which have suffered declines as a result of the draining include the snipe, lapwing and red shank. “Unless significant conservation efforts to save these farmland birds are undertaken there is no reason why they won’t disappear,” said Brian Caffrey, BirdWatch Ireland’s Atlasco-ordinator.

One farmland bird which has already become extinct here is the corn bunting.

The small, streaked, grey-brown bird, often associated with hay meadows, was recorded in modest numbers in the previous 1988-1991 Atlassurvey but has since fallen off the radar.

Its demise is also linked to more intensive farming practices, including the increased use of fertiliser and pesticides, which is thought to have deprived the bird of its food supply of weed seeds.

Another victim of the shifting patterns of agriculture, in this case the switch from tillage to pasture, is the yellowhammer.

The small seed-eating bird with its distinctive yellow plumage, which is found mainly in arable areas, has seen its numbers drop by more than 40 per cent in the past 20 years. It is now largely confined to a few counties in Leinster where arable farming is still practised.

Perhaps the most positive news from the survey is the great spotted woodpecker’s re-emergence. The birds, which became extinct in Ireland after widespread woodland clearances of the 17th and 18th centuries, have been spotted recently in several counties across Leinster.

The fledgling population, part of a natural overspill from Britain, is thought to number in the region of 50 pairs.

The survey also charts the remarkable comeback of the buzzard. Hunted to the brink of extinction in previous centuries, the broad-winged bird of prey is now thriving across the country thanks to more awareness and less persecution.

“When the data is validated, we’re going to see a striking change in the map for the buzzard,” Mr Caffery said.

Significantly, the research reveals the extent to which climate change is affecting some of Ireland’s seasonal migrants.

The most high-profile casualty has been the cuckoo (down 30 per cent), which appear not to be migrating here from sub-Saharan Africa in the same numbers.

Ornithologists believe that desertification, in particular the expansion of the Sahara which is expanding southward at a rate of 48km a year, is making the arduous 7,000km migration more and more hazardous for the birds.

Climate change is also thought to be behind a sharp fall-off in the number of bewick’s swans wintering in Ireland.

The birds, distinguishable from the more common mute swan by their yellow beaks, travel from Siberia to winter here. However, rising temperatures have prompted the birds to cut short their annual journey westward, stopping off in more easterly locations on mainland Europe.

One of the most conspicuous signs of global warming has been the recent invasion of little egrets.

The small white herons, which are steadily colonising the southern half of the country, were not recorded in the previous survey.

The rising temperatures have also seen an influx in warblers such as the blackcap, a rarity even 20 years ago, but now commonly found in back gardens.

According to Mr Caffery, blackcaps, which have one of the most distinctive songs, are not only migrating here in greater numbers from Africa during summer but are staying on through the winter as well on account of the milder temperatures.

The survey also recorded an upsurge in ravens, an upland bird which feeds mainly on carrion.

The closing date for records to be submitted to the survey’s co-ordinators is January 31st.

BirdWatch Ireland is still asking the 2,500 Irish volunteers who have taken part in the survey and to members of the public to send in their sightings.

Of particular interest to researchers are sightings of reclusive species like the barn owl and the long-eared owl, whose numbers have traditionally been hard to assess.