High Quality Content by WIKIPEDIA articles! The Gray Catbird (Dumetella carolinensis), also spelled Grey Catbird, is a medium-sized northern American perching bird of the mimid family. It is the only member of the "catbird" genus Dumetella. Like the Black Catbird (Melanoptila glabrirostris), it is among the basal lineages of the Mimidae, probably a closer relative of the Caribbean thrasher and trembler assemblage than of the mockingbirds and Toxostoma thrashers. In some areas it is known as the Slate-colored Mockingbird.