Scaled quail (Callipepla squamata) populations declined 50% from 1954-56 to 1990--91 in a 125 km2 study area. Food habits based on a sample of 150 quail crops remained unchanged. Abandonment of farms, land use, and climatic changes were hypothesized to be major factors responsible for the population decline.
Schemnitz, Sanford D.
"Scaled Quail Habitats Revisited - Oklahoma Panhandle,"
National Quail Symposium Proceedings: Vol. 3
, Article 20.
Available at: http://trace.tennessee.edu/nqsp/vol3/iss1/20