Numididae – Guineafowl

The family known as Numididae (Guineafowls) along with Cracidae (Guans, Curassows & Chachalacas), Megapodiidae (Megapodes), Odontophoridae (New World Quails) and Phasianidae (Partridges, Pheasants, Grouse & Allies) are Galliformes, one of the largest of bird orders.

The family Numididae are sometimes called ‘pet speckled hen’, or ‘original fowl’ or guineahen. They are endemic to the continent of Africa and rank among the oldest of the gallinaceous birds.

Phylogenetically they branched off from the core Galliformes after the Cracidae (chachalacas, guans, and curassows) and before the Odontophoridae (New World quail). An Eocene fossil lineage Telecrex has been associated with guinea fowl; Telecrex inhabited Mongolia, and may have given rise to the oldest of the true phasianids, such as blood pheasants and eared pheasants, which evolved into high-altitude, montane-adapted species with the rise of the Tibetan Plateau. While modern guinea fowl species are endemic to Africa, the helmeted guinea fowl has been introduced as a domesticated bird widely elsewhere.

The insect eating and seed-eating, ground-nesting birds of this family resemble partridges, but with featherless heads, though all members of the genus Guttera have a distinctive black crest, and the Vulturine Guineafowl has a downy brown patch on the nape. Most species of guineafowl have a dark grey or blackish plumage with dense white spots, but both members of the genus Agelastes lack the spots (as do some wild variants of the Helmeted Guineafowl). While several species are relatively well-known, the Plumed Guineafowl and the two members of the genus Agelastes remain relatively poorly known. These large birds measure from 40–71 cm (16–28 inches) in length, and weigh 700–1600 grams. Females outweigh the males.

Southern Crested Guineafowl Guttera edouardi – ©Dubi Shapiro

The species for which information is known are normally monogamous, mating for life, or are serially monogamous; however, occasional exceptions have been recorded for Helmeted and Eastern Crested Guineafowl, which have been reported to be polygamous in captivity. All guineafowl are social, and typically live in small groups or large flocks. Though they are monogamous, species of the least-derived genera Guttera, Agelastes and Acryllium tend toward social polyandry, a trait shared with other primitive galliformes like roul roul, and Congo peafowl.

Guineafowl travel behind herd mammals and beneath monkey troops where they forage within manure and on items that have fallen to the understory from the canopy. They play a pivotal role in the control of ticks, flies, locusts, scorpions and other invertebrates. They pluck maggots from carcasses and manure.

Guineafowl are, without exception, strong fliers. Their breast muscles are dark (evidence of their aerobic metabolism), enabling them to sustain themselves in flight for considerable distances if hard-pressed. Grass and bush fires are a constant threat to these galliformes and flight is the most effective escape.

Some species of guineafowl, like the Vulturine, may go without drinking water for extended periods, instead sourcing their moisture from their food. Young guineafowl, known as keets, are very sensitive to weather, in particular cold temperatures. Both parent birds share food finding and brooding the keets.

Guineafowl species are found across sub-Saharan Africa, some almost in the entire range, others more localised, such as the Plumed Guineafowl in west-central Africa and the Vulturine Guineafowl in north-east Africa. They live in semi-open habitats such as savanna or semideserts, while some, such as the Black Guineafowl, mainly inhabit forests. Some perch high on treetops. The Helmeted Guinea fowl has been introduced in East Africa, the West Indies, the United States, Britain, and India, where it is raised for food or as pets.