Curlew eggs are being rescued from nests on airfields and reared and released in a Government-funded project to help the threatened bird.
The scheme, to give the birds a “head start” by taking eggs from military and civil airfields in the east of England before incubating, rearing and releasing them in a habitat where they can thrive, builds on a pilot project last year.
The eggs, collected by staff from Government conservation agency Natural England and partners, are beginning to hatch at Pensthorpe Natural Park, Norfolk, and the Wildfowl and Wetlands Trust’s reserve at Slimbridge, Gloucestershire.
When old enough, the birds reared in Norfolk will be released into agricultural grassland at the Queen’s Sandringham estate and wet grassland at nearby Wild Ken Hill, a regenerative farming, rewilding and conservation estate.
The curlews reared at Slimbridge will be released on Dartmoor.
Ground-nesting curlews are attracted to airfields, which mimic the natural open grassland they prefer, and can often be relatively safe from predators such as foxes due to the high security fences that surround them.
But officials said curlews nesting close to runways pose a risk to air safety, and before the project, eggs laid on airfields would have been destroyed under licence to avoid the risk of collisions between birds and aircraft.
Curlews are the largest European wading bird, which winter on estuaries and breed on rough grassland, moorlands and bogs, and have faced significant declines in the breeding population.
Conservationists say the intensification of agriculture, along with planting trees on moorlands, is likely to have been important in causing past declines, while the birds also face high levels of predation from foxes.
They are “red listed” in the UK due to concerns over their conservation status, and wildlife experts say urgent action is needed to help them.
This year’s project continues the work of last year’s pilot, which saw 79 birds reared at Pensthorpe and released in Norfolk.
The progress of those birds was monitored by the British Trust for Ornithology, which ringed the fledglings and fitted some with satellite or radio tags to follow their progress.
Some 26 had been spotted by this May, the majority on the east shore of the Wash bay near the release site, and mostly with wild-reared curlew, although some had ventured further afield to Lincolnshire, Somerset and even the Exe estuary in south Devon.
GPS tags have shown that grassland habitat is especially important for young curlews, with the birds only gradually moving to use more coastal habitats nearby.
More GPS tags and radio transmitters will be fitted to the birds this year to track their movements and learn more about their habits.
The team behind the scheme, funded by the Environment Department (Defra), say the data gathered from the young curlews will not only support the project but wider conservation efforts to reverse the declining fortunes of the species, including creating networks of habitat for threatened wildlife.
Graham Irving, wildlife management lead adviser at Natural England, said: “At Natural England we want to see nature thriving everywhere.
“The decline of the curlew is one of England’s most pressing conservation challenges and we’re proud to be leading this innovative project, which we hope will make a significant difference to the fortunes of this iconic bird in the east of England.”
Chrissie Kelley, head of species management at Pensthorpe Conservation Trust, said: “Working together is vital to help reverse the decline of the curlew. Pensthorpe Conservation Trust are thrilled to play a significant part in aiding the recovery of such an important species, by rearing and releasing chicks saved from the airfields.”