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Résumé :
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Wetland reedbeds of the French Atlantic coast are important stopover sites for millions of migratory birds each year. Most reedbed are wet along the year due to tides, some others, less well known, are drying out in summer. How do both kind of reedbeds differ in migratory species number and abundance? In the Adour estuary (southern part of the French Atlantic coast), two sites were compared according to similar capture-ringing protocol during two years (August and September). Habitat surveys have mainly focused on reed parameters such as height, stem diameter, density and stratification. Results showed that the wet reedbeds attracted higher species-diversity and higher numbers of aquatic and transsaharian migratory species. Reeds are taller, thicker, less dense and have a weaker herbaceous stratum. The dry reedbeds harbour species tolerant to lower hydric conditions (Locustella naevia, Acrocephalus paludicola). In order to regulate the spreading of woody or exotic invasive plant species (Acer negundo, Baccharis...) and to attract more transsaharian migrants, we propose to maintain a constant water level in those reedbeds currently drying out in summer.
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