The spread of the Collared Dove Streptopelia decaocto in Europe: colonization patterns in the west of the Iberian Peninsula

Capsule The pattern and timing of spread are examined, particularly in Extremadura, and theories on speed and extent of spread and possible competition with related species are discussed. Aims To describe the present pattern of the spread of the Collared Dove in one of the few areas in Europe where the process is still active, in the light of the hypothesis of general expansion in Europe. Methods Information was obtained from field data collected in 1996-97 and from responses by local observers to a questionnaire. We recorded data on the presence in localities, numbers of birds, extent of colonization, date the first birds were sighted, and confirmed nesting. Results The first settlements in Extremadura were observed less than ten years ago. The timing indicates that the process of expansion in Extremadura is now at a stage of full development, enabling us to study the mechanism involved. The colonization shows a clear northwest-southeast direction to the interior from coastal areas of Iberia. The species first established itself in urban-areas, from which it slowly but steadily expanded towards rural areas. Conclusions The expansion of the species has been very rapid, and is still active in Extremadura. The colonization pattern shows a clear directionality (northwest-southeast), beginning with urban nuclei, followed by expansion into rural areas.