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Standardized point counts were used to quantify the relative abundance and diversity of birds in three distinct terrestrial habitats at the Four Canyon Preserve, a mixed-grass prairie natural area in northwestern Oklahoma. Surveys conducted in 2014 detected 38 species including most breeding birds expected to occur at the site. Relative abundance and frequency of occurrence were calculated for species observed, and total relative abundance and mean species richness were calculated for habitats and for the Preserve as a whole. Total abundance and mean species richness were highest for wooded canyon and lowest for upland grassland habitats. Results were compared with years 2005 and 2007 assessments to identify potential changes in the avifauna of the Preserve. Increases were noted for Cassin’s Sparrow (Aimophila cassinii), Western Meadowlark (Sturnella neglecta), and Northern Bobwhite (Colinus virginianus).