TESTING AGRI-ENVIRONMENTAL DELIVERY FOR FARMLAND BIRDS AT THE FARM SCALE: THE HILLESDEN EXPERIMENT
Shelley A Hinsley*1, John W Redhead1, Paul E Bellamy1,2, Richard K Broughton1,
Ross A Hill1 & Richard F Pywell1
1 CEH Wallingford, Maclean Building, Crowmarsh Gifford, Wallingford, Oxfordshire, OX10 8BB, UK
2 Current address: RSPB, The Lodge, Sandy, Bedfordshire, SG19 2DL, UK
* Email: sahi@ceh.ac.uk
Modern agriculture is a major driver of habitat and landscape modification and various agri-environment schemes have been devised to mitigate its detrimental impacts on biodiversity. The Hillesden experiment is a farm-scale study devised to test the effectiveness of management prescriptions under the UK Environmental Stewardship Scheme to conserve and enhance biodiversity across a range of taxa, and to inform future development of management options. The study farm is c. 1000 ha of typical lowland heavy land growing autumn sown winter wheat, oil-seed rape and beans. The study, initiated in 2005/06, is a randomised block experiment with five replicates of three treatments, with treatments in contiguous blocks of 70-80 ha. Treatments comprise i) the basic requirements of cross-compliance (CC), ii) entry level stewardship (ELS) (removal of 1% of land from production with the creation of a small number of simple options) and iii) entry level stewardship extra (ELS X) (removal of 5% of land from production with a diverse range of options). Habitat data for the whole farm has also been obtained using airborne remote sensing techniques (height data from LiDAR and land use from reflectance data), the site being flown in August 2007. Birds have been censused by spot mapping in two winters and two breeding seasons, the census being based on a total of c. 16 km of hedgerow transects. Bird usage of sown bird food patches has also been recorded in winter. The study will run for five years and here we present preliminary results for the first two years (pre- and post establishment of options). First indications are that bird numbers increased in the winter following the establishment of the habitat options under ELS and ELS X and that the numbers of breeding territories in the second breeding season also subsequently increased. However, variation across the replicates was large and results were largely statistically non-significant. The effects of scale on the ability to detect significant changes in organisms as mobile as birds are also discussed.
Shelley Hinsley is an avian ecologist with interests in bird population dynamics in relation to habitat fragmentation, habitat quality and landscape structure. Previously based at CEH Monks Wood for 19 years, she has worked on various aspects of woodland and hedgerow bird ecology including distribution, abundance and reproductive success and how these are influenced by both habitat and bird quality. She has a special interest in the application of airborne remote sensing in quantifying habitat structure and the effects of climate on habitat quality.
