Apparently rare. Bill black, slender, very sharply hooked. Facial area and legs red (orange in immature). Adult male slaty black with upper and under tail-coverts, basal half of tail, and tip of tail white. Adult female brownish black above; tail as in male. Immature like female but brown above and more prominently streaked below.
Habits and Behavior
A rather sociable bird of open freshwater marshes where it feeds mostly on Pomacea snails, hunting by beating somewhat clumsily over the marsh. Regularly circles at considerable hights above its marsh, and even soars fairly often.