Western jackdaw amounts of silicaceous and calcareous grit to aid digestion of vegetable food and supply dietary calcium. Opportunistic and highly adaptable, the western jackdaw varies its diet markedly depending on available food sources. They have been recorded taking eggs and nestlings from the nests of the skylark ("Alauda arvensis"), Manx shearwater ("Puffinus puffinus"), razorbill ("Alca torda"), common murre ("Uria aalge"), grey heron ("Ardea cinerea"), rock pigeon ("Columba livia"), and Eurasian collared dove ("Streptopelia decaocto"). A field study of a large city dump on the outskirts of León in northwestern Spain showed that western jackdaws forage there in the early morning and
Bryan's shearwater Bryan's shearwater The Bryan's shearwater ("Puffinus bryani") is a species of shearwater that may occur around the Hawaiian Islands. It is the smallest species of shearwater and is black and white with a bluish gray beak and blue tarsi. First collected in 1963 and thought to be a little shearwater ("Puffinus assimilis") it was determined using DNA analysis to be distinct in 2011. It is rare and possibly threatened and there is little information on its breeding or non-breeding ranges. It is named after Edwin Horace Bryan Jr. a former curator of the B. P. Bishop Museum at Honolulu. On