Overview
Easily spotted at coastal sites during the winter, Europe’s largest wading bird feeds in groups on tidal mudflats, saltmarshes and nearby farmland.
During the spring and summer, curlews migrate to their breeding grounds – mostly in upland areas – raising their chicks in areas of rough pasture, heather moorland and wetlands.
Though formerly widespread across the UK, breeding populations are increasingly concentrated in upland areas – former breeding haunts in lowland areas have largely been lost due to changing farming practices.
During the breeding season, males deliver a loud and impressive ‘bubbling’ song to attract mates and defend their territories. This atmospheric song is surely one of the most evocative sounds of the British countryside.
International importance of UK population
There are around 68,000 pairs of breeding curlews in the UK – between 19 and 27 per cent of the global breeding population.
Whilst some of ‘our’ birds spend the winter in Ireland and France, we receive an influx of Scandinavian-breeding curlews, here taking advantage of our relatively mild winter. This means there are around 150,000 birds during the winter.
This means the UK is arguably the most important country for curlews in the world.
Curlews are in trouble
Curlews breed across northern Europe and Russia, as far east as Lake Baikal.
Unfortunately, national bird monitoring schemes show breeding populations are declining sharply across much of their range.
In 2008, curlews were deemed of global conservation concern and became listed as Near Threatened on the IUCN Red List of Threatened Species.
Steep declines have been particularly evident in the UK. Between 1995 and 2012, the breeding populations declined by 55 per cent in Scotland and 30 per cent in England.
Elsewhere in the UK, the population has declined by 81 per cent in Wales (between 1993 and 2006) and by 82 per cent in Northern Ireland (between 1985-87 and 2013).
The results of the latest Breeding Bird Atlas produced by the British Trust for Ornithology (BTO) found the breeding range has declined by 17 per cent in mainland Britain and a staggering 78 percent in Ireland.
Curlews are in real trouble. Regional and possibly even country-level extinctions are now a possibility.
While curlews are declining across the countryside as a whole, it is of note that they are faring better within some upland areas where management for grouse shooting is practised.
What’s the problem?
A significant amount of research has gone into investigating curlew populations and reasons behind their declining numbers.
The evidence to date suggests declines are largely due to poor breeding success alongside the loss of breeding grounds.
Like many wading birds, curlews lay their eggs in a nest on the ground – known as a ‘scrape’. The parents incubate the eggs for about four weeks, before the young leave the nest and roam around with their parents for a further four weeks, until fledging.
Studies from across Europe have found that in most cases breeding pairs are failing to raise enough young to maintain stable populations.
Egg predation by mammals and birds has emerged as a key factor behind poor breeding success. However, this abundance of predation is in itself associated with changes in land-use and management.
Farming is essential to maintain the mosaic of grassland and wetland habitats curlews need, but large-scale grassland improvement ultimately leads to the degradation and eventual loss of breeding habitat. Changes in grazing pressure can also have a more direct impact in the form of nest trampling by livestock.
Other changes in land use can lead to loss and fragmentation of breeding habitat, especially forestry. Whilst predation may not be the only factor driving the decline, it is clear that in some areas where predators are controlled, curlew populations are faring better.
The RSPB, along with the UK’s statutory nature conservation agencies, believe the curlew should now be considered the UK’s highest conservation priority bird species and a recovery programme is urgently required.
Efforts made to save our curlew population will play a critical role in the global conservation efforts. Conserving and managing the mosaic of habitats required by breeding curlews is likely to benefit a wide range of other flora and fauna.
How can you help?
From eating chocolate to attending events there's lots you could be doing to help our curlews, why not check out some of our ideas here.
