The wading bird, with a drastic fall in numbers over recent years, is in danger of disappearing from some countryside sites.
Under the Darley Beck Curlew Project villagers have surveyed some 500 fields, to watch and wait for the chicks to arrive. Just three fledglings survived the season.
Barry Carter, a retired company director and keen photographer, is one of a handful of neighbours and friends who banded together to find out what was happening.
The curlews weren't calling as they used to, he said.
Mr Carter said the problem wasn't that the birds weren't producing young; they were. But they proved a feast for carrion crows, foxes, and black headed gulls.
"There's an unbelievable amount of predation," he said. "Of more than 20 nests, there are just three chicks left. The rest have perished.
"This unbelievable dip in curlew numbers is going to get dramatically worse," he warned. "They are just not producing enough chicks."
The project was masterminded by a local farmer, Clive Meldon White who had noticed a decline in birdsong in the valley, and enlisted some 40 volunteers.
Work began in the spring, dividing fields around Thornthwaite into manageable patches.
Volunteers would survey their sites, charting what they saw from buzzards to grasses. Then, with thermal imaging cameras, they were able to map out the nests.
As the chicks have reared, they watched progress from a distance. And then their decline, with just a handful surviving.
'It makes you feel alive'
Mr Carter started with 18 fields, then took on a few more. What he thought might take him three hours a week, in walking the countryside, has grown to almost 25.
He has come to enjoy it, he said. The curlews led them on a "mesmerising trail" to find the nests, while he has seen species he didn't know remained in Nidderdale.
One chick, he has watched for weeks, sitting for hours outside the field and finding himself returning almost every day. Once he catches a glimpse, he said, "it's all golden again".
He chuckled: "I'm a big softie at heart. It's so wonderful, to go out looking for curlews, and to find hares boxing. You've got roe deer, hopping around you, jumping over walls.
"It does actually make you feel alive. It's a fantastic feeling. There's a lot of benefits you get from volunteering."
Most farmers have helped, he said, holding off the grass cutting when they've been aware of nests in their fields. A local gamekeeper helped create a safe space for a breeding pair.
There has long been a worrying decline in the UK's breeding population of curlews, with suggestion that numbers have nearly halved over 25 years.
The picture, said Mr Carter, is more stark than anticipated.
"The findings are absolutely dramatic. It's actually worse than we thought," he said.
"At this early stage we can see they are disappearing at an unbelievable rate, with so few chicks getting to fledgling stage. We can count the chicks on one hand."
There are many factors at play, volunteers believe, and much to change. Greater grants for farmers would be a start, while dog walkers have a responsibility to keep pets on a lead.
"Maybe we can help with giving curlew chicks a chance to survive, by thinking how we cut," said Mr Carter. "From this small survey, it isn't enough to keep up curlew numbers.
"Curlews live for 25 years - we are seeing birds but it's the same ones again and again. These curlews are dying, and new birds aren't coming through in the right numbers."
The curlew conservation project, driven by Nidderdale landowner Clive White, is supported by the Farming in Protected Landscapes programme and the Nidderdale AONB.
Mr White, who has produced suckler beef for 35 years, enlisted the support of farmers who have permitted volunteers to carry out detailed surveys.
Supported by ecologists, volunteers were trained to monitor the curlews, identify nest sites, and record habitat and field management. It is hoped findings can be shared at Nidderdale Show in September.
Curlews are in decline across the UK. In 2008, the curlew was deemed of global conservation concern and listed as ‘Near Threatened’ on the Red List of Threatened Species.
For more pictures see www.bazcarterphotos.com
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