Recent increase in waterbirds in Bourgogne (France)

摘要

Comparison between old anti recent bird studies in Bourgogne enables us to trace a history of the Breeding birds of the region over the past century: The cumulated number of bird speciess, which have bred at: least once in the region, is 187. An estimated 140-160 species of birds are though to have bred during the 19(th) century and 160-170 nowadays. During the past century 26 new breeding species have colonized while 7 have disappeared (population renewal rate 10,5%). These changes in breeding bird populations are felt in ail types of habitats: open habitats species are diminishing water birds are increasing with a net grain of 14 species over the past century. This strong increase in water bird species diversity is also noted at the national and European scales. new aquatic species are those linked to large open waters; or generalists with large territories, while "marsh" species linked to shallow wetlands, tend to decrease. These changes are clearly linked to the creation of large and relatively stable water bodies (quarries, reservoirs, better species protection and a general eutrophication of wet habitats. This phenomenon is also known from other taxa (fish, invertebrates): increase of local diversity caused by invasive species and erosion of global diversity by loss of specialized species.