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Gambel’s Quail, Callipepla gambelii, are gregarious birds commonly found in the southwestern deserts of the United States and Northwestern Mexico. With expanding urbanization, these birds are often found in exurban and suburban areas where they have access to food sources that may differ from those used by birds living in rural-urban fringes. To investigate this question, we compared the morphology and nutritional physiology of quail sampled at sites varying with respect to land use and cover. We hypothesized that quail living in urbanized areas have access to a greater variety of food sources and to more stable food resources, and so are in better body condition, than quail residing in less urbanized areas. We sampled birds at locations in the Phoenix, Arizona (USA) area, that vary with respect to land use and cover types. Birds were weighed and we measured their body length and chest circumference. A blood sample was collected from the jugular vein of each individual for analysis of plasma glucose, total proteins, triglycerides, and free glycerol using commercially available kits. Consistent with our hypothesis, birds living in more urbanized environments were longer, and they had larger chest circumferences and greater circulating triglyceride concentrations than birds living in less developed areas, suggesting greater access to lipid-rich foods. In addition, the abundance of grass at the sampling sites was associated positively with plasma protein concentrations but negatively with plasma free glycerol levels. Areas with more grass may provide birds with less dietary fats than the diet of urban birds, resulting in the breakdown of triglycerides into free glycerol. These findings are the first to demonstrate an association between urbanization and the morphology and nutritional physiology of Gambel’s Quail.