The Aplomado Falcon, Falco femoralis, is a medium-sized falcon of the Americas. The species' largest contiguous range is in South America, but not in the deep interior Amazon Basin. It was long known as Falco fusco-coerulescens or Falco fuscocaerulescens, but these names are now believed to refer to the Bat Falcon (AOU 1948).
It is very slender, long-winged, and long-tailed, the size of a small Peregrine Falcon (length of 30"?40 cm or 12"?16 inches, average wingspan of about 90 cm or 36 in) but only half the weight (250"?475 g or 9"?17 oz). This resemblance in shape to the hobbies accounts for the former name Orange-chested Hobby. "Aplomado" is an unusual Spanish word for "lead-colored", referring to the blue-gray areas of the plumage. Spanish names for the species include Halcón fajado and Halcón aplomado.
Illustration from Pacific Railroad Surveys
In adult birds, the upperparts are dark blue-gray, as is much of the head, with the usual falcon "moustache" contrasting sharply with the white throat and eyestripe. The upper breast continues the white of the throat; there are black patches on each side of the lower breast that meet in the middle; the belly and thighs, below the black patches, are light cinnamon. The tail is black with narrow white or gray bars. Juvenile birds are very similar, but their upperparts and belly band are blackish brown, the chest is streaked with black, the white on the head and breast is buffy, and the cinnamon on the underparts is paler.
It may be confused with the Bat Falcon and the Orange-breasted Falcon, which have similar white-black-rust patterns below, but those species are built more like Peregrines and have solidly blackish heads and darker rufous bellies. These two species are generally considered to belong to the same lineage as the Aplomado Falcon. Two other Falco species of the Americas, the Merlin and American Kestrel, seem to be closer to the Aplomado group than most other falcons, but the relationships of all these lineages are fairly enigmatic. All that can be said with some certainty is that they diverged as part of an apparently largely western Holarctic radiation in the Late Miocene, probably around 8"?5 million years ago.
The Aplomado Falcon's habitat is arid grasslands, savannahs, and marshes. It feeds on insects and small vertebrates, especially birds, and is often seen soaring at twilight hunting insects and eating them on the wing. It also hunts at fields being burned, at which many birds of this species may gather. In Brazil, Aplomado Falcons have been observed following Maned Wolves and chasing birds that the wolves flush (Silveira et al. 1997).
Range, history, status
It ranges from northern Mexico and Trinidad locally to southern South America, but has been extirpated from much of its range, including northern and central Mexico except for a small area of Chihuahua. Until the 1950s it was found in the extreme southwestern United States, and reintroduction efforts are under way in West and South Texas. It began to reoccupy its former range in West Texas and southern New Mexico in the 1990s. Documentary evidence for these naturally occurring birds was obtained in New Mexico in 1991, and sightings built steadily through that decade and the next, leading to successful breeding in 2002. Sightings and nesting activity continue to the present.. Expansion of the reintroduction program to that area has met with criticism, because technically, all Aplomado Falcons in New Mexico are now classified as part of an "experimental" (reintroduction) population.
As such, while they are still legally protected from hunting, they are not protected by Endangered Species Act requirements to preserve habitat and the like. It is believed that mainly habitat destruction caused the species' (near-)disappearance from the US and hinders reestablishment of a wild breeding population; thus, a coalition of environmental groups is attempting to have full protection restored so as not to jeopardize the success of the expanding wild population and the reintroduction efforts.