iris is brown and legs are black. It is most readily distinguished from the similar Woodhouse's scrub-jay by the plain (unstreaked) throat and breast, and the mantle contrasting less with the head and wings. Its range somewhat overlaps with the Woodhouse's scrub-jay, but, where they co-occur, the two species seem to show ecological and morphological character displacement (Curry et al. 2002). Distribution and habitat It is native to the Sierra Madre Oriental, Sierra Madre Occidental, and Central Plateau of Mexico as well as eastern Arizona, western New Mexico and western Texas in the United States. Its preferred habitat is montane pine-oak forest. Ecology In the winter, the Mexican jay's diet consists mainly of acorns and pine nuts, which are stored in the autumn. However, they are omnivorous in all seasons and their diet includes a wide variety of plant and animal matter, including invertebrates, small amphibians and reptiles, and birds' eggs and nestlings (McCormack and Brown 2008). It has a cooperative breeding system similar to that of the related Florida scrub-jay, with several birds helping at a nest; these "helpers" are usually immature offspring of the dominant pair from the previous 1–2 years, but also include apparently unrelated flock members. Footnotes References Bhagabati, N. K. & Horvath, E. G. (2006): Mexican jay social group size varies with habitat in northeastern Mexico. Journal of Field Ornithology 77: 104–110. Brown, J. L. & Horvath, E. G. (1989): Geographic Variation of Group Size, Ontogeny, Rattle Calls, and Body Size in Aphelocoma ultramarina. Auk 106: 124–128. Curry, Robert L.; Peterson, A. Townsend & Langen, T.A. (2002): Western Scrub-Jay (Aphelocoma californica). In: Poole, A. & Gill, F. (eds.): The Birds of North America 712. Academy of Natural Sciences, Philadelphia, PA & American Ornithologists' Union, Washington, D.C. Online version, retrieved 2007-FEB-25. (requires subscription) Ligon, J. D. & Husar, S. L. 1974 Notes on the behavioral ecology of Couch's Mexican jay. Auk 91: 841–843. Madge, Steve & Burn, Hilary (1994): Crows and jays: a guide to the crows, jays and magpies of the world. A&C Black, London. McCormack, JE & Brown, JL. (2008) Mexican jay (Aphelocoma ultramarina). In The Birds of North America Online (A Poole, ed.). Cornell Laboratory of Ornithology: Ithaca, NY. McCormack, JE & Berg, EC (2010): Small-scale divergence in egg color along an elevation gradient in the Mexican Jay: a condition-dependent response? Auk 127: 35–43. McCormack, John E., Peterson, A.T, Bonaccorso, Elisa, & Smith,