In late fall and early winter > 2,000 Common Coots (Fulica atra) may gather on the small, shallow Lake Krankesjön in southern Sweden, where they dive for submerged plants. Casual observations indicated that intraspecific kleptoparasitism was common throughout these flocks. Kleptoparasitic attacks mostly occurred shortly after a Common Coot surfaced with food and before it had ingested much of it. Attacked birds rarely resisted, and kleptoparasitic individuals had a success rate of 85% (n = 290), including cases when the victim managed to keep part of the food. Kleptoparasitic Common Coots used a mixed strategy, alternating between parasitism and self-feeding.