SPA description
(information as published 2001)
Thames Basin Heaths
The Thames Basin Heaths SPA is a composite site that is located
across the counties of Surrey, Hampshire and Berkshire in southern
England. The open heathland habitats overlie sand and gravel
sediments which give rise to sandy or peaty acidic soils,
supporting dry heathy vegetation on well-drained slopes, wet heath
on low-lying shallow slopes and bogs in valleys. The site consists
of tracts of heathland, scrub and woodland, once almost continuous,
but now fragmented into separate blocks by roads, urban development
and farmland. Less open habitats of scrub, acidic woodland and
conifer plantations dominate, within which are scattered areas of
open heath and mire. The site supports important breeding
populations of a number of birds of lowland heathland, especially
Nightjar Caprimulgus europaeus and Woodlark Lullula
arborea, both of which nest on the ground, often at the
woodland/heathland edge, and Dartford Warbler Sylvia
undata, which often nests in gorse Ulex sp. Scattered
trees and scrub are used for roosting.
Together with the nearby Wealden Heaths SPA and Ashdown Forest
SPA, the Thames Basin Heaths form part of a complex of heathlands
in southern England that support important breeding bird
populations.
Qualifying species
For individual species accounts visit the Species
Accounts section
This site qualifies under Article 4.1 of the
Directive (79/409/EEC) by supporting populations of European
importance of the following species listed on Annex I of the
Directive:
During the breeding season;
Dartford Warbler Sylvia undata, 445 pairs
representing at least 27.8% of the breeding population in Great
Britain (Count as at 1999)
Nightjar Caprimulgus europaeus, 264 pairs
representing at least 7.8% of the breeding population in Great
Britain (Count mean (1998-99))
Woodlark Lullula arborea, 149 pairs representing at
least 9.9% of the breeding population in Great Britain (Count as at
1997)
Note:
Many designated sites are on private land: the listing of
a site in these pages does not imply any right of public
access.