21 September 2005
Image: Andy Hay
The recovery of the corncrake population in Scotland, which started in the early 1990s, is continuing. A translocation project is underway to assist the return of the corncrake to England.
Corncrakes are closely related to moorhens and coots. They spend the winter in Africa, returning to the UK in spring. The males arrive in April, and start singing to attract a female as they return from migration. Their distinctive rasping ‘crex crex’ call gives them their scientific name: Crex crex.
Corncrakes used to be widespread and common across the UK, but about 150 years ago it was noticed that they were declining from the east. Knowledge of this familiar but secretive bird was very sketchy and, although it was suspected that the decline was linked to changes in management of grass fields and meadows, it was unclear what was happening.
The decline continued through the 20th century until, by the 1990s, they were restricted almost entirely to the islands on the north and west coasts of Scotland. Corncrakes have been lost from many areas of Europe and, although some big populations remain in eastern states, most countries have lost at least 20% of their corncrakes.
By the late 1980s, it was clear that the UK corncrake population was in a critical state. However, it was also evident that our understanding of this bird’s ecology was relatively poor. RSPB research revealed that corncrakes need tall (20 cm+) invertebrate-rich vegetation throughout the breeding season, that the birds can easily walk through.
It also found that the species is adversely affected by mechanical mowing. This information was used to develop and refine management techniques, which were trialled on RSPB reserves, notably on the Hebridean islands of Coll and Islay. Measures included the adoption of ‘corncrake friendly’ mowing methods.
This means that fields are mowed in a way which pushes the birds towards cover in which they will be safe once the crop is cut without forcing them to cross an already-cut area. This usually means mowing fields from the centre outwards, rather than the more traditional out-in, which traps the birds in the centre.
Other measures include changes in grazing management to provide areas of vegetation cover throughout the breeding cycle, and the provision of corncrake ‘corners’ and ‘corridors’ to ensure that sufficient cover is available during the early and late parts of the breeding season.
Image: The RSPB
Once successful management techniques had been developed, these were implemented in the key corncrake areas. Fieldworkers advised farmers and crofters and offered them grant aid to support corncrake friendly practices through the RSPB/Scottish Crofting Foundation/Scottish Natural Heritage Corncrake Initiative.
The key techniques were demonstrated on nature reserves so that other land managers could see at first hand what is involved. The RSPB pressed successfully for the inclusion of corncrake measures in agri-environment funding schemes for farmers.
Working in partnership with crofters and farmers has resulted in changes in grassland management leading, in turn, to an increase in the UK corncrake population. It has also benefited other important species such as the great yellow bumblebee, a BAP species for which the RSPB is lead partner.
The corncrake remains in a precarious position, but current signs are encouraging. The population recovery, which started in the early 1990s, continues, with a survey of Core Areas (Orkney and the Hebrides, generally encompassing around 90% of the national population) recording 1,042 calling males in 2004.
The next challenge is to expand the species’ range. Management work will be targeted towards areas with high re-colonisation potential. The RSPB is undertaking a trial to re-establish corncrakes in eastern England. Though it is too early to say whether this will be successful in the long term, a first breeding record at the release site is encouraging.
The Corncrake Initiative remains an important mechanism for funding corncrake management. However, favourable grassland measures under agri-environment schemes (such as the Environmentally Sensitive Areas scheme and the Rural Stewardship Scheme in Scotland) are increasing the land under favourable management. This will be essential if the recovery of the corncrake is to be assured.
The recovery of the corncrake in Scotland has been the result of a partnership between the RSPB, Scottish Natural Heritage, the Scottish Executive, farming and crofting organisations, and the agricultural communities of the north and west coast.
The re-introduction of corncrakes to the Nene Washes is part of Action for Birds in England, a conservation partnership between English Nature and the RSPB with the Zoological Society of London. We would also like to thank Chester Zoo.