Corbicula fluminea (Müller, 1774) (Bivalvia, Corbiculidae) eaten by oystercatchers

In this paper we report on oystercatchers feeding on Corbicula fluminea, a recent invader in the river Rhine. Oystercatchers are specialised molluscivores. They could reach these freshwater bivalves during low river level in the summer of 2003 and in the end of March 2004. The shell remains after consumption have a characteristic damage pattern: the valves still adhere by the ligament and only one of the valves has a (small) piece broken off ventrally. Due to lack of access, oystercatchers cannot use this food source on a regular base as they can with mussels and cockles in tidal areas exposed every low tide. Feeding irregularly on Corbicula shows the oystercatcher’s flexibility in foodchoice.