Laughing falcon
The laughing falcon (Herpetotheres cachinnans), also called the snake hawk (erroneously, since it is not a hawk), is a medium-sized bird of prey in the falcon family (Falconidae), the only member of the genus Herpetotheres. This Neotropical species is a specialist snake-eater. Its common and scientific names both refer to its distinctive voice.
Its English name comes from its loud voice, as does the specific name cachinnans, Latin for "laughing aloud" or "laughing immoderately".[2] The generic name Herpetotheres refers to its preferred food; it is Latinized Ancient Greek, derived from [h]erpeton (ἑρπετόν, "reptile") + therizein (θερίζειν, "to mow down").[3]
Its relationships with other members of the Falconidae are unclear. Traditionally it has been placed in the subfamily Polyborinae with the caracaras and forest falcons, but the American Ornithologists' Union's North American Check-list Committee now places it in the same subfamily as the true falcons, while the South American Check-list Committee places it with the forest falcons but not the caracaras,[4] and it has also been considered a subfamily of its own.[5]
The laughing falcon is 46 to 56 cm (18 to 22 in) long[6] and has a wingspan of 79 to 94 cm (31 to 37 in).[7] As usual among birds of prey, the females are bigger, weighing 600 to 800 g (1.3 to 1.8 lb) compared to the males' 410 to 680 g (0.90 to 1.50 lb).[6]
Adults have a pale buff head, changeable between a more brownish and an almost white hue according to feather wear and individual variation. The broad black face mask stretches across the neck as a narrow collar, bordered with white. On the crown, the feather shafts are dark, producing a somewhat streaked effect. The upper wings and back are blackish brown. The uppertail coverts are whitish buff again, and the rectrices are barred black and whitish, ending in white. The underside is uniformly pale buff; there may be a bit of dark speckling on the thighs, however. The underside of the wing is pale rufous-buff, sometimes with some dark spotting on the underwing coverts. The tips of the primary remiges are barred with pale grey below, their bases are quite rufous. The iris is dark brown, the bill is black with a pale yellow cere; the feet are also pale yellow.[5]
Immature birds differ little from adults; they have lighter margins to the back feathers, producing a scalloped effect. The light parts of the plumage are almost white, paler than in adults; the unfeathered parts are also paler. Nestlings are covered in peculiarly dense down, reminiscent of a duckling's; they are generally brownish buff, darker above, and already show the blackish facial marks of the adults.[5]
