Berkshire’s atlas records have been combined with those of Bedfordshire, Buckinghamshire, Hertfordshire and Oxfordshire, which together provide information on changes in the distribution of the breeding birds of over 9000 square kilometres of inland southern England. By pooling tetrad level distribution data over a wider area, we are able to see trends and habitat relationships more clearly than with individual county data. Published by the five county bird clubs, the atlas is online here: