Rissa tridactyla

The black-legged kittiwake is a circumpolar species of the Northern Hemisphere. In France, they nest mainly on cliffs from Finistère to Pas de Calais. There is also an “urban” colony in Boulogne sur Mer, where gulls nest on buildings and where an artificial colony for kittiwakes was built. It is a sort of “gull shelf” that compensate for the eviction of individuals from the city buildings. The species is present in winter along the entire French coastline, generally in the high seas. In France, numbers are threatened mainly by predation on colonies by peregrine falcons, common ravens and even crows. The black-legged kittiwake is relatively coastal when breeding and pelagic during the inter-breeding period. It feeds on the surface.

While some colonies in Normandy and Boulogne-sur-Mer have been well studied during the breeding season, there are currently no data on the movements of adults and immatures during the breeding season, nor on Breton individuals.

On cliffs such as Pointe du Raz (Finistère), birds are captured on their nests by ornithologists trained in rope work. The demography of Kittiwake colonies in Finistère has been monitored for many years by a team of scientists led by Emmanuelle Cam from
Marine Environmental Sciences Laboratory Institut Universitaire Européen de la mer (Université de Bretagne Occidentale), but this is the first time these individuals have been tracked using GPS tags.

In Boulogne sur Mer, black-legged kittiwake nests on artificial structures are more accessible. This urban colony is monitored by a scientific team from the Centre d’Etudes Biologiques de Chizé (CEBC) led by Olivier Chastel, and has already been the subject of a telemetry study in 2014, which determined the adults’ feeding areas during nesting.

The gulls, both adults and juveniles, are fitted with OT10 GPS tags attached to a Teflon harness installed like a small backpack around their wings. The system is designed to last from several months to over a year, making it possible to track the movements of the kittiwakes not only during breeding, but also during migration and wintering.

    ^{Migratory in France}

^{Breeder in France}

    ^{Wintering in France}