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
Bird extinction which results to the downfall of extinction. The most common disease affecting birds is Salmonellosis, which originates from the Latin name of salmonella. Infected birds pass bacteria in their fecal droppings. Other birds then become ill when they eat food contaminated by the droppings. Bird extinction Out of the approximately 10,400 known bird species, about 1,300 (13%) are classified as threatened with extinction, 9% as near threatened and of the remaining 78% many populations are declining. There is a general consensus among scientists who study these trends that if human impact on the environment continues as it has one-third of