The black-collared hawk, known scientifically as Busarellus nigricollis, is a striking bird of prey, unique as the sole member of its genus. It presents a vivid cinnamon-rufous plumage across its body, with a contrasting black crescent on the upper breast and black flight and tail feathers. The head is a pale buff white, adorned with black streaks, and the eyes gleam with a reddish-brown hue. The legs of this raptor are a bluish white, while the cere and bill are a stark black.
Adults can be identified by their bright cinnamon-rufous coloration, black crescent on the upper breast, and the black streaks on their white to buff head. The immature black-collared hawk is marked by more extensive black blotching and rufous barring on the tail, with a more pronounced pale chest area and barred upper wing surfaces. Their brown eyes distinguish them from the reddish-brown eyes of adults.
The black-collared hawk favors the lush environments of subtropical or tropical moist lowland forests, as well as subtropical or tropical swamps.
This bird has a broad range, extending from western Mexico down through to Uruguay, making its home across a significant swath of Latin America.
The black-collared hawk is known to nest in large trees, often near water bodies. It may also adapt to human-altered landscapes, nesting in shade trees within coffee plantations or suburban locales. The nest is crafted with green leaves, providing a fresh lining for the eggs.
Females lay a clutch of three to five eggs, which are dull white and adorned with spots of pale yellow-brown or red-brown, along with a few darker freckles. Unfortunately, further details on the reproductive habits of this species remain elusive.
A piscivorous raptor, the black-collared hawk primarily feeds on fish. Its diet is supplemented by a variety of other prey, including water bugs, large insects, snakes, lizards, frogs, snails, other molluscs, crustaceans, small birds and their nestlings, rodents, and other small mammals.
The IUCN Red List currently classifies the black-collared hawk as Least Concern, indicating a stable population without immediate threats to its survival.
In the past, the black-collared hawk was thought to resemble Buteogallus aequinoctialis in form and appearance. However, it is now understood to be more closely related to the milvine kites and sea eagles, sharing specific morphological traits such as the fusion of basal phalanges of the inner toe, which aids in capturing prey.