The Crow Corvus corone hybrid zone in southern Denmark and northern Germany
Version of Record online: 10 AUG 2005
Volume 147, Issue 4, pages 649–656, October 2005
How to Cite
HAAS, F. and BRODIN, A. (2005), The Crow Corvus corone hybrid zone in southern Denmark and northern Germany. Ibis, 147: 649–656. doi: 10.1111/j.1474-919x.2005.00422.x
- Issue online: 10 AUG 2005
- Version of Record online: 10 AUG 2005
- Received 27 January 2004; revision accepted 14 January 2005.
In hybrid zones genetically differentiated populations meet and interbreed. As they result from ongoing divergence and potential speciation, such zones provide opportunities to study how different factors affect this process. One well-known avian hybrid zone is that between the Hooded Crow Corvus corone cornix and Carrion Crow C. c. corone, which extends throughout much of Europe. We compare the current position and width of the zone in southern Denmark and northern Germany with that described in detail by Meise in 1928. A GPS technique was used to determine the geographical position of more than 1000 Crows in established pairs in which all individuals were classified as either Carrion, Hooded or hybrid phenotype. The data show that the Carrion Crow has expanded northwards and that this is most pronounced at the eastern side of the study area. Here the hybrid zone has moved around 19 km. However, the width of the zone seems to have remained stable over time. Possible reasons for why the zone may have moved are discussed.