The Black-collared Hawk (Busarellus nigricollis) is a bird of prey found inArgentina, Belize, Bolivia, Brazil, Colombia, Costa Rica, Ecuador, El Salvador, French Guiana, Guatemala, Guyana, Honduras, Mexico, Nicaragua, Panama, Paraguay, Peru, Suriname, Trinidad and Tobago, Uruguay, and Venezuela. Its habitat is subtropical and tropical moist lowland forest and subtropical and tropical swampland.
The adult has a white head, tinged with beige, and with black shaft streaks on the crown. The upperparts, underparts, and mantle are bright cinnamon-brown, and paler on the chest. There is a black crescent on the upper breast. Scattered black shaft stripes are on the back. The flight and tail feathers are black with the base and tail barred brownish-red. The eyes are bright reddish-brown. The bill is black, and the legs are bluish-white. The young are similar to the adult, but blotched with black, including the crown, and the barring on the tail is more extensive. The pale area of the chest is also more clearly marked. The upper wings are barred, and the eyes are brown.
The nest is in a large tree, usually near water, but sometimes in shade trees in coffee plantations or suburban areas. The nest is lined with green leaves. The female lays three to five dull white eggs that are spotted with pale yellow-brown or red-brown and a few dark freckles. The diet consists mainly of composed fish. It will also take in water bugs and occasionally lizards, snails and rodents.