Enhancement of farmland biodiversity is a key objective of agri-environment
schemes in Europe, and conservation of the rare and threatened cirl buntin
g (Emberiza cirlus) has been a key objective for the Countryside Stewardshi
p Scheme (CSS) in south Devon, UK. Cirl bunting numbers increased by 83% on
land entering CSS management agreements between 1992 and 1998, compared wi
th an increase of just 2% on adjacent countryside not managed under CSS. Th
e increase in cirl buntings on stewardship land was part of a wider regiona
l increase in abundance rather than a redistribution of birds away from lan
d not under stewardship. In 1998, 22% of all UK cirl buntings were breeding
on land under CSS agreements and a further 16% of birds were within 0.5 km
of land under stewardship. All but one of the 27 agreements that gained ci
rl buntings were within 2 km of cirl bunting breeding sites in 1992, with m
ore distant agreements failing to be colonised even if they offered a range
of potentially beneficial prescriptions. Agreements providing grass margin
s around arable fields, weedy winter stubbles and open patches of grassland
next to scrub tended to gain additional cirl buntings. Grass margins and w
eedy winter stubbles constitute important food-rich habitats for cirl bunti
ngs and other farmland birds, and should be encouraged in future agri-envir
onment agreements and schemes. (C) 2001 Elsevier Science Ltd. All rights re
served.