You might think that a bird standing over 40cm tall with long yellow legs, big yellow eyes, powerful black tipped yellow bill and black and white bars on its wings would be easy to spot - but that couldn’t be further from the truth. The stone-curlew is one of the most elusive birds in Suffolk, and it’s one of the most wonderful and strange birds too.   

There are a little over 100 breeding pairs in the county, and they are very rarely encountered unless you know where to find them and, even then, they are easily overlooked due to their amazing camouflage – but more about that later.  Stone-curlews are a member of the bird family known as ‘thick-knees’, so-called due to their prominent knee joints. There are only 10 species of thick-knees in the world, and just one of these, the Eurasian stone-curlew, is found in Europe.  

Resting at a 'stone-curlew plot' Resting at a 'stone-curlew plot' (Image: Andy Hay / RSPB Images) Suffolk is an important place for the stone-curlew, as it supports approximately 30% of the national population. Found on two opposite sides of the county: the Brecks in the west and the Sandlings in the east, both areas are distinguished by their free-draining sandy, stony soil, which attracts this species for a very special reason.  

Stone-curlew nest on open ground and are very particular about where they build their nests. They look for heavily grazed grassland or arable farmland when fields are still bare or the crops just emerging. These birds usually lay a clutch of up to two eggs, with some pairs having a second brood. Nests are often built amongst stones scattered on the surface, which gives great camouflage.  

Their feathers offer great camouflage too. Sandy brown feathers with darker brown-black flecks blend perfectly with the sandy ground. They sit or stand motionless for long periods during the day, saving most of their activity for the cover of darkness. Stone-curlew are rarer now than they were 100 years ago, since then they have suffered a steep population decline due to a loss of suitable nesting places.

Stone curlews are hard to spot.Stone curlews are hard to spot. (Image: Andy Hay / RSPB Images) Grass heathlands deteriorated due to a lack of grazing from livestock and rabbits, nesting sites were lost due to increases in built development and places that stone-curlew had traditionally nested on were converted to forestry or arable farmland.

Although arable land can provide nesting habitat for stone-curlew, these nests are often at risk of destruction during farming operations. But there is good news.  The Stone-curlew Project was established in 1985 to help bring back this critically endangered species and will be celebrating 40 years of conservation work next year. Thanks to a lot of joined up working between conservationists, farmers and landowners to manage habitat specifically for stone-curlew to breed, their population has been gradually increasing. 

Many patches of grass heathland have been restored and new areas created. Farmers have stepped forward and signed up to create new places for stone-curlew to nest on their land. These two-hectare ‘plots’ are left fallow and kept bare or sparsely vegetated to encourage nesting out of crops and away from farming operations. 

The stone curlew's eggs laid in a bean field. The stone curlew's eggs laid in a bean field. (Image: David Mackey / RSPB Images) We are incredibly fortunate to have a dedicated team of 10 RSPB volunteers that help to monitor the Suffolk population of stone-curlew each year, contributing their expert knowledge and considerable time. Breeding pairs are counted and monitored, and they work closely with farmers and gamekeepers to locate nesting birds and protect them. This collaborative effort results in greater breeding success each year.  

In the long-term, we aim to provide enough grass heathland and arable nest plots to accommodate a sustainable population of stone-curlew that are not reliant on intensive nest protection measures to thrive.  

The small size of the population means that it is highly vulnerable to change, natural or otherwise. For example, in 2013 extremely cold weather in early spring caused approximately 20% of the UK stone-curlew population to perish. Also, land managers recently moved swiftly to increase grazing livestock and create bare ground with farm machinery on grass heathland areas favoured by nesting stone-curlew after rabbit populations that traditionally grazed these sites reduced drastically due to disease. Such quick action by the landowners helped to maintain nesting habitat for the species.

Tim Cowan on the lookout for these beloved birds. Tim Cowan on the lookout for these beloved birds. (Image: P Hackett / RSPB Images) These examples show the importance of conservation efforts to maintain a healthy population should incidents like these occur. The good news is that successful breeding seasons in recent years should see the population increase again as time moves on. 

Stone-curlew will likely now have left our shores to go to their wintering grounds in southern Spain and North Africa where they will stay before returning to the UK in March and April next year. I think I can safely speak for the project team and the amazing farmers, landowners and volunteers that make this long-term project happen when I say we look forward to the stone-curlew returning to Suffolk again next spring.