Saltcedar (Tamarix sp.) is a non-native woody invasive species that reduces groundwater supplies. Natural resource agencies and private landowners are seeking to eradicate this exotic species from watersheds in western Kansas, including from along the Cimarron River on the Cimarron National Grasslands. Our research studied the effects of saltcedar eradication on species richness and abundance of avian populations in riparian habitats. Nine, 500-m transects were established. Three were located in areas of dense saltcedar, three were in treated areas where saltcedar had been removed, and three were in areas dominated by cottonwood (Populus deltoides). For four consecutive years (2006–2009), each of the nine transects was walked twice during the typical avian breeding season (22 May to 5 July). The number of individuals for each bird species seen or heard within 50 m of the 500-m transect line was recorded. Twenty-seven bird species were found to be nesting in saltcedar. Saltcedar eradication efforts may negatively impact local populations of these species. Yellow-breasted Chat (Icteria virens), Field Sparrow (Spizella pusilla), and Indigo Bunting (Passerina cyanea) were found only in saltcedar-encroached areas and therefore may be particularly negatively affected by saltcedar removal. The removal of the woody vegetation created more grassland habitat thereby potentially benefiting the seven species of grassland birds found exclusively in the treated areas. Riparian areas dominated by cottonwood had the highest species richness with 36 species found, including 14 species that were found only in these areas. If successful, the current efforts of the US Forest Service (USFS) to establish and maintain cottonwood forest along the Cimarron River likely will result in significantly increased avian species richness.