Designed by Paul Smith 2006. This website is copyrighted by law.
Material contained herewith may not be used without the prior written permission of FAUNA Paraguay.
Photographs on this web-site were taken by Paul Smith, Hemme Batjes, Regis Nossent,
Alberto Esquivel, Arne Lesterhuis, José Luis Cartes, Rebecca Zarza and Hugo del Castillo and are used with their permission.
FALCONIDAE - FALCONS
Twelve species which can be split into two subfamilies (see below). Typical falcons have long, pointed wings and strong, hooked bills. In general falcons are lightweight and slender, but deceptively powerful, with ankylosed thoracic vertebrae contributing to their impact power. The neck is short in all but the caracaras and the pectoral muscles are large allowing rapid flight. Feet have an elongated central toe and a sturdy hind toe each with sharp, highly-curved talons adapted for grasping. Eyes brown with two foveae facilitating vision in all species with the exception of the Chimango Caracara which has only one. Head-bobbing is used in predatory species to judge relative distance. Nostrils are rounded in all species except the caracaras, opening through a fleshy cere. Plumage is tightest and primaries stiffest in fast-flying species. The great majority of species have 10 primaries (the 11th vestigial), 11 secondaries and 12 retrices. There is a single, complete annual moult beginning in the breeding season. Flight feathers are lost sequentially in pairs beginning in the middle of the primaries and secondaries and proceeding outwards. Tail moult proceeds outwards from the central pair. Females are larger than males.
Subfamily Polyborinae: Caracaras and Forest-falcons
Four genera and six species in Paraguay. Lack tomial "teeth" on the bill.
Caracara "Crested-Caracaras" - Large scavenging caracaras. Wings long and pointed, tail long and neck long, forming cross-like silhouette in flight. Large, compressed bill with viciously-hooked tip. Legs long, talons long, thin and blunt. Sides of head and chin naked. Semi-terrestrial. Different wing formula, 10 primaries and 13-14 secondaries. Slit-like nostrils
Milvago "Caracaras" - Small, lightweight, unspecialised caracaras. Wings long and blunt. Tail rounded. Legs weak. Claws sharp and curved. Head mostly feathered. Semi-terrestrial. Slit-like nostrils.
Herpetotheres "Laughing Falcon" - Stocky, medium-sized, large-headed falcon. Short, rounded wings and moderatly long, strongly-rounded tail. Stout, untoothed bill. Legs short, covered with rough, small, hexagonal scales - likely a form of protection against snake bites..
Micrastur "Forest-falcons" - Secretive forest-dwelling falcons, more often heard than seen. Wings short and rounded. Tail long and rounded. Bill short, deep and untoothed. Long legs. Feathers around ear form a ruff, ear-openings large. Extremely keen sense of hearing used in hunting.
Subfamily Falconinae: Falcons and Falconets
Two genera and six species in Paraguay. Tomial "teeth" on both mandibles thought to assist in the killing of prey.
Spiziapteryx "Spot-winged Falconet" - Small Chaco falconet of uncertain affinities. Wings rounded, tail long and rounded. Bill without a tooth. Legs and claws powerful. Nests within colonial nests of Monk Parakeet Myiopsitta monachus.
Falco "Falcons" - Long, pointed wings and long tail adaptations for rapid pursuit hunting. Bill short, strong and distinctly toothed. Legs short and powerful. "Capped" appearance with "moustache" on sides of head. Both sexes have brood patches. Females larger than males.
REFERENCES
Brown L & Amadon D 1989 - Eagles, Hawks and Falcons of the World - Wellfleet Press.
Cade T 1982 - The Falcons of the World - Collins.
Campbell B & Lack E 1985 - A Dictionary of Birds - T & AD Poyser.
Ferguson-Lees J & Christie DA 2001 - Raptors of the World - Houghton Mifflin.
White CM, Olsen PD & Kiff LF 1994 - Falconidae Handbook of the Birds of the World Volume 2 - Lynx Ediciones.
