Use of habitat by the California black rail (Laterallus jamaicensis coturniculus), a subspecies threatened in California and endangered in Arizona, is not sufficiently well known for effective management. From March 1987 to December 1988, we studied use of habitat by 36 radio-transmittered California black rails at Mittry Lake Wildlife Management Area, Arizona. Birds selected (P 6 cm deep. Birds used areas that were closer to vegetation-type edges, were drier, and had shorter vegetation compared with available habitat (P