| Titre : | Significance of habitat structures as a regulatory mechanism for the breeding density of Carrion Crows (Corvus corone corone) |
| Auteurs : | C. Menzel, Auteur ; E. Strauss, Auteur ; W. Meyer, Auteur ; K. Pohlmeyer, Auteur |
| Type de document : | Article |
| Dans : | Journal of Ornithology (141(2) APR 2000) |
| Article en page(s) : | 127-141 |
| Langues: | Anglais |
| Résumé : | In four regions of Lower Saxony with a total area of 113 km(2) we examined woods and electricity pylons as habitat structures with respect to their frequency distribution and suitability as breeding places of carrion crows. We determined real population densities and calculated a hypothetical breeding density in relation to habitat structures in order to test a possible regulative effect of these structures on regional differences in settlement density of Corvus c. corone. The regional capacities indicated a hypothetical breeding density 3.2 to 7.6 times higher than was proven in reality, Even in a medium-sized territory of 0.5 km(2) (a value to be found in literature) a 1.4 times higher density is still possible. Furthermore, the regional nest distribution established by the index of dispersion was random, but the habitat structures showed clumping. Neither the habitat structures on their own nor in combination with territory size can be regarded as definite mechanisms of regulation in the choice of territory and breeding place and thence of the distribution and settlement density of Corvus c. corone. The possible influence of food supply and non-breeding populations on distribution patterns and settlement densities is discussed. |



