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
Ron Scarlett the New Zealand owlet-nightjar, the Scarlett's duck (which was named by Storrs L. Olson), and the Hodgens' waterhen. The Scarlett's shearwater ("Puffinus spelaeus") described in 1994 by Richard N. Holdaway and Trevor H. Worthy is named in his honour too. Ron Scarlett belong to the founders of the New Zealand Archaeological Association which was established in 1954. He was also a member of the Ornithological Society of New Zealand where he has frequently written contributions for the quarterly scientific journal, "Notornis". In 1996 he was awarded an MBE for his services to science. Scarlett died at age 91 on 9