EUROPEAN BIRD SPECIES HAVE EXPANDED NORTHWARDS DURING 1950-1993 IN RESPONSE TO RECENT CLIMATIC WARMING
Authors: Gregorio Moreno-Rueda
Abstract: Because temperature affects the distribution limits of many organisms, global warming may provoke an advance of distribution ranges polewards. This work examines whether European birds have advanced their distribution ranges mainly northwards from 1950 to 1993 in response to climatic warming. Bird species were separated into different categories according to their distribution. The findings show that European birds advanced their distribution ranges northward more than southward. Only northernmost species showed the contrary pattern, probably because their northward expansion was constrained by the Arctic Sea. Birds from the central Europe advanced their distribution ranges primarily northward, strongly suggesting that the change in distribution was occasioned by climate warming, as a change due to other causes predicts equal frequency of species advancing southwards and northwards.