Bordetella aviumis the etiologic agent of bordetellosis, a highly contagious upper respiratory disease of young poultry. Its prevalence among domesticated turkeys is well-known, but information on prevalence of this bacterium in other birds is limited. A survey of the prevalence of B. aviumin wild and domesticated birds was conducted from June 1998 to January 2000, using tracheal cultures and serology. Of 237 blood samples from 61 species, 100 individuals from 41 species had antibodies against B. aviumas determined with a microtiter agglutination test. Nine isolates of B. aviumwere cultured from 128 tracheal samples. Ribotype analysis of seven isolates from mallards (Anas platyrhynchos), one from a wild turkey (Meleagris gallopavo), and one from a Canada goose (Branta canadensis) indicated that they represent three strains, two of which were indistinguishable from clinical isolates from domesticated turkeys. Bordetella aviumis present in wild bird populations of multiple species. Transmission from free-living avian populations to domesticated poultry populations may be possible and should be examined.