The black-capped vireo (Vireo atricapilla) breeds in a relatively narrow area of the south-central United States and north-central Mexico. It was likely extirpated from Kansas by the 1930’s and is now endangered in Oklahoma and much of the northern, eastern, and central portions of its range in Texas. Prior to being listed as endangered, less than forty birds were found in the state of Oklahoma in 1985. Among the most influential factors contributing to its decline are: nest parasitism by the brown-headed cowbird (Molothrus ater), habitat deterioration through destruction, and natural successional changes resulting from fire suppression.

The black-capped vireo is a Federally endangered, migratory bird whose largest breeding population in Oklahoma is found within the Wichita Mountains. These birds visit the Refuge from March to September each year to find a mate, rear young, and travel south to wintering habitat in Mexico. The black-capped vireo has been designated an endangered species by the U.S. Fish and Wildlife Service and is a focus of extensive habitat restoration and other management decisions on which this species depends. Habitat management activities such as prescribed burning and mechanical treatments restore habitats to their historic conditions, thereby benefiting black-capped vireos.