The yellow-legged gulls of the Lac de Serre-Ponçon nest on the shores directly on the ground, in the rocks, or on the grass. They build their nests in the shelter of natural cavities or dig a shallow basin in the soil they scrape with their legs. The birds then line the cavity with a more or less large quantity of various plants (grasses, twigs, moss, algae, etc.) and food debris which they summarily pile up.