The Avon Atlas 2007-11 summarises the work of some 530 observers in the 17 hectads of the Avon BTO area between 2007 and 2011. All 403 tetrads were surveyed, the majority for four hours in summer and four in winter. Avon Atlas 2007-11 compares the results with the previous breeding Atlas in 1992 and the winter Atlas in 1986. Detailed statistics are presented on density in different habitats based on the concept of the observed rate per hour.