Saving the stone-curlew
A rare summer visitor to southern England and East Anglia, Eurasian Stonecurlew has historically suffered catastrophic declines in the UK. Keith Betton explains why he got involved with an RSPB project to help project the species.
Keith Betton explains why he got involved with a project to help project a rare and declining summer visitor to southern England and East Anglia.
March is by far my favourite month because it marks the return of a bird that I just can’t get enough of: Eurasian Stone-curlew. Most UK birders have to travel a long way to see one, and even those that live close to its haunts rarely see it because this shy and very cautious wader only nests in places where it rarely sees people.
The genus Burhinus consists of 10 species that all have large eyes and are very similar in appearance, with different combinations of sandy brown plumage with stripes and spots. They are variously named as thick-knees or dikkops in some places, and in years gone by farmers in East Anglia referred to them as ‘Wailing Heath Chicken’. Eurasian Stone-curlew is a summer migrant to this country from southern Spain and North Africa. It is present right across the Palearctic to north-west India, and is found on open steppes with stony ground and sparse vegetation. Across its range it can be found up to 1,000 m above sea level. Where I live, in Hampshire in southern England, however, it is found in the lowlands.
Losses and gains
The species was once widespread from Dorset to Yorkshire. A population of 1,000-2,000 pairs in the 1930s was already much reduced from that which had existed in the 19th century, but a more rapid decline followed, with numbers hitting an all-time low of fewer than 170 pairs in the 1980s. This fall was largely due to the loss of suitable grassland habitat brought about by lack of grazing, both by sheep and rabbits, and the conversion of permanent pasture to arable farmland. As a result, the birds were forced to nest within sparsely vegetated, spring-sown arable crops where the eggs and young were vulnerable to agricultural machinery. Since the 1980s, work by the RSPB and others to protect the nests and young has led to a recent increase in numbers – and that is when I became involved. I saw my first Eurasian Stonecurlew in Hampshire about 30 years ago. It was at long range through a telescope, and the bird skulked away from view as soon as it realised it was being watched. Over the next 20 years I never really enjoyed anything other than
distant views of birds, mostly on private land that was completely inaccessible to the public.
I knew the RSPB was doing a great job of advising farmers on the creation of plots for stone-curlews. So in 2010 I decided to volunteer to help with watching them. The benefit would be two-fold: I would be monitoring the birds and enabling them to have the best chance of success, and I would be able to enjoy watching them at the same time. I eventually ended up co-ordinating several volunteers across 10 farms.
The first birds are usually back at their breeding sites by mid-March, at which point we will be out looking for them, although in 2019 at least two had returned to one site by late February. They are often best detected at this time by their nocturnal calling.
Special measures
Most of the Hampshire population of approximately 30 pairs now breeds on specially prepared plots created to provide safe areas away from agricultural operations. These have the additional benefit of minimising the impact of disturbance by the public, since very few are visible from footpaths. These plots are managed by the farmers, who are paid by the government to provide open stony ground for nesting, plus buffer zones for chicks to hide in. Areas with trees and bushes are avoided as they provide opportunities for Carrion Crows and Common Buzzards to predate the nests. In April and May we locate nests and then alert the farmers to the birds’ presence so that farming operations in those areas are carried out with extra care. These measures have allowed numbers to increase, and without this level of intervention it has been estimated that the population would decline by about 4% per year.
It is often quite a challenge to establish whether birds are breeding as they may travel up to 3 km to feed and, to complicate matters, there are nonbreeders that move between sites. A productivity of around 0.6 chicks per breeding pair per year is thought to be enough to maintain the population, and in most recent years we have managed to achieve that, although the birds are so secretive that the chicks are often hard to locate to prove fledging. To understand whether the young have survived and fledged we mark the chicks using a combination of plastic colour rings.
Even though most Eurasian Stonecurlews choose to nest on our specially created plots, a few prefer nearby fields where they do not realise that within a matter of weeks they will be surrounded by a forest of wheat. If we can find these nests the law allows us to do a bit of light ‘gardening’ to ensure that they are not swamped.
At one farm they nest on strips of commercially harvested turf, and we may potentially have the challenge of lifting the eggs and remaking the nest to allow operations to continue. The nest is a very basic structure of small stones that the birds place in a circle – presumably to reduce the chance of the eggs getting wet. So long as the nest is remade carefully the birds will go straight back to it.
Working together
While stone-curlews continue to nest on working farmland the only way the population can be maintained is through proactive liaison with farmers. A sign of the success of 30 years’ effort is that in 2009 the species was downgraded from Red to Amber in the list of Birds of Conservation Concern. Unless suitable areas of downland can be recreated and protected, such conservation action needs to be maintained at the current level. At the moment the RSPB is working with more than 200 farmers to ensure that the UK population of some 350 pairs is maintained and increased.
I am frequently struck by how much the farmers care about these birds.
In a recent harvest we knew that two well-grown chicks were hiding in a field of rape that the farmer was due to cut. A team of four of us tried to coax the chicks out but they were staying put.
The farmer gingerly drove his combine harvester towards where the birds were, staying in radio contact with me at all times. He paused as he got to the final strip of rape, and the chicks made a dash for it. To be sure of their safety we scooped them up and kept them safe in the back of my car until the harvesting had been completed. One of them left a large dropping in my car as a thank you note! Such moments are priceless.
I have gone from watching this remarkable bird through a telescope at long range to holding it in my hand and getting up close and personal – which is an amazing feeling. But an equally incredible feeling comes from knowing that I and my colleagues are helping to save a species that would be crushed under the wheels of tractors if we were not involved. ■