Report on scarce migrant birds in Britain in 2004-2007Part 2: passerines

摘要

This is the second part of the tenth 'Report on scarce migrant birds in Britain', dealing with the relevant passerine species recorded during 2004-07. Non-passerines were treated in part 1 (Brit. Birds 106: 368-404), which includes a fuller introduction to the data presented here, but it is worth reiterating that for many species this report marks the 50th year of systematic data gathering. This dataset provides a unique insight into trends that may not (yet) be apparent elsewhere and also supports other data sources (such as the Rare Breeding Birds Panel reports) in revealing changes in population levels and migration patterns, both at home and abroad.