Several bird species are known to nest in cave entrances, including swallows (Hirundo rustica) (a large colony in the disused underground oil depot at Cattedown, Plymouth), Swifts (Apus apus), Jackdaws (Corvus monedula) and Wrens (Troglodytes troglodytes). Dippers (Cinclus cinclus) have been reported nesting in the Dart River Cave, Buckfastleigh. Feral pigeons (Columba livia) can occur in large numbers breeding in caves around the Torbay area and in the Cattedown caves at Plymouth.