Bird of the Year 2011: involving public in the analysis of regional variation of bird songs

The yellowhammer (Emberiza citrinella) is a common bird of open areas whose song exhibits easily distinguishable dialects. The dialects are tied to the final part of its song. Some, especially older publications claim that yellowhammer's dialects can be divided into two broad groups with predominantly Eastern and Western European distribution, with a borderline intersecting Central Europe. Until recently, yellowhammer dialects have only been thoroughly researched in Denmark and in some parts of Germany. In the Czech Republic, a detailed study was carried on in connection with the"Bird of the Year"campaign, during which the general public was involved in collecting song recordings at various localities. Thanks toa project called "Czech Yellowhammers Dialect", more than 2600 recordings from throughout the Czech Republic were collected within three years. The recorded songs were then classified into one of the seven traditionally acknowledged groups; some new, not yet documented ones were also discovered. The distribution of the dialects generated a dialect mosaic with a clearly established borderline between individual dialects. Mixed singers were found along the borderlines. A borderline between two dialect groups, crosscutting Western Bohemia, was also found. It was proved once again that for a success of..