Bullfinch by John Harding

Bird Atlas 2007–11 was a resounding success with over 216 million birds of 520 species and subspecies recorded from over 3,870 10-km squares during the four winters and four breeding seasons of fieldwork. The main results can be found in the book, Bird Atlas 2007–11: the breeding and wintering birds of Britain and Ireland (available from the BTO shop and from BirdWatch Ireland) which includes species accounts for almost 300 species, over 1,300 maps and seven chapters detailing the planning, field methods, data capture methods and data analysis techniques, along with a chapter summarising the emerging patterns and changes. In these pages you can find additional resources.


All the maps from Bird Atlas 2007–11, and those from previous Britain & Ireland atlases, can be viewed freely in our new Bird Atlas Mapstore, but be sure to consult the published books for all the statistics and interpretation.

Pattern and Change

Using the data on groups of species we can see patterns and changes in the avifaunas of Britain and Ireland over the last 40 years.


Full details of patterns of coverage and effort can be found in Chapter 5 of the Bird Atlas book but you can find a short overview here. See also monitoring progress for examples of how we gauged effort through the project in order to identify critical gaps in coverage.


Find out how we brought together different data sources to build comprehensive maps for all species in Britain and Ireland.

Population Estimates

Many previous atlases have derived and published estimates of population size. In the UK and Ireland population estimates are now produced by other methods.

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