NOTE BREVE

DO MAN-MADE NESTING SITES PROMOTE THE INCREASE IN NUMBERS AND SPATIAL SPREAD OF THE EURASIAN CRAG MARTIN PTYONOPROGNE RUPESTRIS IN EUROPE?

Paul ISENMANN1

RESUME

Several small bird species in the Western Palearctic are dependent on man-made nesting sites in cities and villages for their reproduction. This is the case for the Common Swift (Apus apus), the Pallid Swift (Apus pallidus), the Bam Swallow (Hirundo rustica), the House Martin (Delichon urbica), and to a lesser extent, the Alpine Swift (Apus melba), the Red-rumped Swallow (Hirundo daurica) and the Black Redstart (Phoenicurus ochruros). Since some of these species have widely adopted buildings as nesting sites, they could spread considerably and increase their numbers, especially in those areas where natural nesting sites are not available. In this respect, growing urbanization in the 19th and 20th centuries has greatly favoured all of these species’s population dynamics. Nevertheless, any detailed information on the process for each species is lacking. There are some indications that a supplementary species, the Eurasian Crag Martin

Rev. Écol. (Terre Vie), vol. 56, 2001.

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