The broad black mask is diagnostic. In flight, shows buffy patch in primaries similar to that of Yellow-headed Caracara. Measures 20 in.
Fairly common and widespread in lowlands and foothills; generally to 3,900 ft, rarely up to 5,900 ft. Often perches conspicuously at forest edge and in open areas with scattered trees; feeds primarily on snakes. Calls mainly at dawn and dusk with a loud, far carrying "gwa-co" (first note higher and louder), thus its local common name, "Guaco".