Puffinus puffinus

Manx shearwaters nest in burrows, sometimes competing with rabbits. While most of the world’s population breeds in the British Isles, the Breton islets of the Sept-Îles and Molène archipelagos are home to small colonies of a few dozen pairs. The Manx shearwater raises a single chick a year for almost 3 months and can make round trips of several hundred kilometres to feed during the breeding season. The species feeds on small fish, cuttlefish and crustaceans at the surface or by diving to depths of 30 to 50 metres. Its gliding flight just over the waves is characteristic. Most adults make a long transatlantic and trans-equatorial migration to spend the winter off South America.

The movements and distribution at sea of Manx shearwaters breeding in France were previously unknown.

Shearwaters are captured in their burrows during the nesting period. Nests are monitored by the managers of the Parc Naturel Marin d’Iroise and the Réserve Naturelle Nationale des Sept-Iles. Adult shearwaters are fitted with OT9 GPS tags that record their geographical position, altitude, tri-axial acceleration and temperature.These small 9g tags transmit the data regularly via the 3G system and are attached to the feathers on the bird’s lower back using special tape. The tags falls out after a few weeks or months as the tape wears down or the feathers moult.

    ^{Migratory in France}

^{Breeder in France}

   ^{Wintering in France}