TIME TO FLY: EXPLORING BIRD MIGRATION By Jim Flegg. BTO, Thetford, 2004. 184 pages; 107 colour photographs; 97 coloured maps; line-drawings and diagrams. ISBN 1-904870-08-2. Paperback, £14.00 (including p&p from the BTO). This book provides a fascinating insight into bird migration to and from (and through and within) Britain & Ireland. The discussion follows `our' migrants far beyond these shores to present a global picture. On the acknowledgments page, the book's concept is described as `a readily-readable distillation of the key information from the inevitably complex wealth of data within The Migration Atlas' (review Brit. Birds 96: 209-210). This is an ambitious undertaking in a publication with 700 fewer (and smaller) pages than its counterpart. The introduction reveals that the author's inspiration came while watching migrants on the clifftops of South Wales; he makes the point that bird movements take place throughout Britain & Ireland, and in all habitats. He adds that, without access to the data banks of the BTO, which runs our birdringing scheme, the book could not have been written. The first three chapters cover the different types of migration; the ways in which birds are adapted, both anatomically and physiologically, for migrating; the reasons they do so and the hazards they may encounter; and the history and methods of studying migration. The following eight chapters, which comprise threequarters of the book, concern the migrants themselves. These are dealt with under seven habitat headings (farmland; woodland; wetlands; estuaries; exposed coasts; towns and gardens; and mountain, moorland and