Falconidae – Falcons, Kestrels & Caracaras

The Falconidae or falcons and caracaras are a family of around 63 species of diurnal birds of prey. The family is divided into two subfamilies, Polyborinae, which includes the caracaras and forest falcons, and Falconinae, the falcons, kestrels and falconets (Microhierax and Spiziapteryx). They differ from the eagles of Accipitridae, in that falcons kill with their beaks instead of their taloned feet. They have a ‘tooth’ on the side of their beak for the purpose.

Saker Falcon Falco cherrug

Falcons and caracaras are small to medium-sized birds of prey, ranging in size from the Black-thighed Falconet, which can weigh as little as 35 grams to the Gyrfalcon, which can weigh as much as 1,735 grams. They have strongly hooked bills, sharply curved talons and excellent eyesight. The plumage is usually composed of browns, whites, chestnut, black and grey, often with barring of patterning. There is little difference in the plumage of males and females, although a few species have some sexual dimorphism in boldness of plumage.

Chimango Caracara Daptrius chimango	Mauritius Kestrel Falco punctatus
All Photographs in this text courtesy of ©Dubi Shapiro

The family has a cosmopolitan distribution across the world, absent only from the densest forest of central Africa, some remote oceanic islands, the high Arctic and Antarctica. Some species have exceptionally wide ranges, particularly the cosmopolitan Peregrine Falcon, which ranges from Greenland to Fiji and has the widest natural breeding distribution of any bird. Other species have more restricted distributions, particularly island endemics like the Mauritius Kestrel.

Red-throated Caracara Ibycter americanus	Laughing Falcon Herpetotheres cachinnans

Most habitat types are occupied, from tundra to rainforest and deserts, although they are generally more birds of open country and even forest species tend to prefer broken forest and forest edges. Some species, mostly in the genus Falco, are fully migratory, with some species summering in Eurasia and wintering entirely in Africa, other species may be partly migratory. The Amur Falcon has one of the longest migrations, moving from East Asia to southern Africa.

Lesser Kestrel Falco naumanni

Prairie Falcon Falco mexicanus

Falcons and caracaras are carnivores, feeding on birds, small mammals including bats, reptiles, insects and carrion. In popular imagination the falconids are fast flying predators, and while this is true of the genus Falco and some falconets other species, particularly the caracaras are more sedentary in their feeding. The forest falcons of the Neotropics are generalist forest hunters. Several species, particularly the true falcons, will stash food supplies in caches. They are solitary hunters and pairs guard territories, although they may form large flocks during migration. Some species are specialists, the Laughing Falcon specialises in snakes, others are more generalist.

Aplomado Falcon Falco femoralis

Sooty Falcon Falco concolor

They are generally solitary breeders, although around 10% of species are colonial, for example the Red-footed Falcon. They are monogamous, although some caracaras may also employ alloparenting strategies, where younger birds help adults (usually their parents) in raising the next brood of chicks. Nests are generally not built (except by the caracaras), but are co-opted from other birds, for example Pygmy Falcons nest in the nests of weavers, or on the ledges on cliffs.

Spot-winged Falconet Spiziapteryx circumcincta

White-rumped Falcon Neohierax insignis

Around 2 to 4 eggs are laid, and mostly incubated by the female. Incubation times vary from species to species and are correlated with body size, lasting 28 days in smaller species and up to 35 days in larger species. Chicks fledge after 28 to 49 days, again varying with size.