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
Giannutri in the northern part which become "garrigue" in the southern. Plants as "arbutus", "Myrtus", "pistacia lentiscus", mock privet, Mediterranean buckthorn, "juniperus phoenicea" and "limonium sommierianum" knew only on Isola del Giglio and Montecristo, grow up on the island. The mild climate has favoured the growth of plants such as "euphorbia", palm trees and wild orchids. The marine flora is abundant in sponges, madreporaria, black coral and red coral. The island, as all that of the Tuscan Archipelago, is a place where the bird migration take a stop along their seasonal movement from North to South. The Audouin's gull, Puffinus yelkouan,