Branta bernicla

Two subspecies are mainly observed in France in winter: the subspecies
bernicla
(dark-bellied) is in the majority and comes from northern Siberia, and subspecies
hrota
(pale-bellied) comes from Svalbard and Canada and winters mainly in the British Isles. An estimated 85% of Siberian Brant numbers winter in France. Estuaries and foreshore areas along the Channel-Atlantic coast, right down to the Bay of Arcachon, are therefore major sites for this herbivorous species, which depends on eelgrass beds. The geese are increasingly turning to alternative resources and now regularly visit salt meadows and sometimes cereal fields close to the coast.

To discover the maritime areas of importance for wintering geese along the French coast, individuals are captured in autumn and winter on foreshore areas where the birds gather to feed. They are equipped with 25g OT25-D GPS beacons that transmit data regularly via 3G and are secured by a lightweight Teflon harness installed like a backpack. Beacons fall off after several months due to Teflon wear.

Migratory in France

Breeder in France

: Wintering in France