La Tour du Valat

Institut de recherche pour la conservation des zones humides méditerranéennes

Titre :	Passage migration of Ortolan Buntings Emberiza hortulana at the German Bight (Helgoland and Schleswig-Holstein) in the period 1964-2000
Auteurs :	Guenther Busche, Auteur
Type de document :	Article
Dans :	Vogelwarte (43(3) AUG 2005)
Article en page(s) :	179-184
Langues:	Allemand
Résumé :	Numbers of migrating Ortolan Buntings decreased dramatically in the German Bight in the period 1964-2000. Ortolan Buntings occur every year during spring and autumn migration. Annual numbers fluctuate between 5 and 76 individuals (average 34). The spring migration period lasts from 29th March to the 6th June, the autumn migration period from 4th August to the 28th October (fig. 2). The observations and median values are presented in table 1. The ratio of numbers recorded during spring and autumn migration for all observations (n = 1030) is 1:1.7. This compares well with observations made in the region between southern Germany and North Jutland where 73-93% of observations are made during spring migration. This phenomenon is explained as loop migration or prolongation of spring migration (e.g. Lower Saxony). The present climate can hardly be the reason for the enormous population declines (in Fenno-Scandinavia). Habitat changes in breeding areas and stopover sites during migration play a more important role in the declines. The fact that in southern France alone 50,000 Ortolan Buntings are killed each year needs to be mentioned in this respect.

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