Diets of Dunlin Calidris alpina and Grey PloverPluvialis squatarolaon the Wash as determined by dropping analysis

Droppings of Dunlin Calidris alpina and Grey Plover Pluvialis squatarola were collected on the Wash, south-east England, and examined for remains of prey species taken. Dropping analysis was found to be useful in describing the diet of these two waders. In addition to confirming known prey species, previously unrecorded prey were discovered: in the case of Dunlin, worms -of the families Spionidae and Phyllodocidae and in the case of Grey Plover, the amphipod crustacean Corophium volutator. Both Dunlin and Grey Plover were found to be taking the opisthobranch mollusc Retusa obtusa¸, a prey species which has not been recorded in the diet of waders before.