The reserve is important for some scarce breeding birds, such as pied avocets on the islands, and western marsh harriers, Eurasian bitterns and bearded reedlings in the reeds. To encourage bitterns to breed, the reed beds have been improved to make them wetter, and the lagoon has been stocked with the common rudd. Typical wetland birds such as the water rail, reed warbler and sedge warbler also appear, and little egrets are common. The reserve has regularly attracted rarities, as its location is important for migrating birds. Ducks and geese winter at Titchwell in considerable numbers, and the reserve shelters the endangered European water vole.