| Summary: | The mean rates of change in annual abundance for 16 farmland specialist breeding bird species based on point counts from three regions of Denmark (West, Central and East) during 1987-2015 inclusive were analysed to see if grassland and arable specialists were showing regional changes that could be related to their respective specializations. Generally, few species showed differences in regional population trends, despite the increasing concentration of mixed (mainly pastoral) agriculture in the West and predominantly arable cultivation in the East. Most grassland and arable specialists were declining in all regions. Only Mew Gull Larus canus showed consistent increases in all regions, Western Marsh Harrier Circus aeruginosus and Common Whitethroat Sylvia communis showed increases in the East and West while Barn Swallow Hirundo rustica showed little change in abundance anywhere during the period. Corn Bunting Emberiza calandra showed significant declines in the East of Denmark in contrast to stable trends in the Central and Western regions, but was declining everywhere since 2003. The results underline the need to understand how individual farmland species exploit specific crops and micro-biotopes as well as the combination of different crops.
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