Earlier arrival of some farmland migrants in western Poland

Abstract

A dataset consisting of observations on the first arrival dates (FAD) of 16 species of birds from a locality in western Poland during the period 1913–1996 is presented and analysed. For 14 of the 16 species, there is evidence of a trend towards earliness in recent years. In the 1970–1996 period this trend was significant for Pied Wagtail, Wood Pigeon, Black Redstart and Barn Swallow, and marginally significant for a further four species: European Serin, Blackcap, Common Nightingale and Red‐backed Shrike. Only two species showed the opposite trend in the 1970–1996 period: Lesser Whitethroat and Whinchat, of which only the former is (marginally) significant. The trend towards earliness was more pronounced for short‐distance (European) migrants than for long‐distance (African) migrants. Short‐distance migrants generally displayed a correlation with spring temperatures in the breeding locality, a feature less obvious in the long‐distance migrants.