Monthly distribution of food items in proportion to the total diet of White-necked Ravens (<i>Corvus cryptoleucus</i>). Data taken from 707 adult birds.
Shaler E. Aldous
Shaler E. Aldous: The White-necked Raven in Relation to Agriculture. In: Research Reports. U.S. Department of the Interior, Fish and Wildlife Service, Washington, D. C. 1942.