Sociable weavers are small birds with a length of about 14 cm and the sexes are alike in both size and plumage colouration. Their upper parts are scalloped with black and their under parts are white; their flanks are marked with black; and they have black face masks. Bills are grey; eyes are brown; legs and feet dark grey.
Pretty little birds, yes, but the most distinctive feature of Sociable weavers is not the birds themselves, but rather their enormous communal nests. The nests, which may house up to 500 birds, can be seen on trees, telephone poles, windmills or virtually any structure within the arid savannah which is their preferred habitat. The nests, made entirely from grass and some thought to be decades old, can become so heavy that the branches to which they are attached snap under the load and it is not unusual to see these nests on the ground.
These enormous nests, probably amongst the largest structures made by any birds, are often subject to predation, particularly by Cape cobras that feed on the eggs and young nestlings, an event that we were excited to witness at a large nest in eastern Namibia. Some of the chambers within the nests are sometimes taken over by Pygmy falcons (Polihierax semitorquatus), Rosy-faced lovebirds (Agapornis roseicollis) and other species for roosting or breeding. The nests may catch fire during the summer months and the nests that are built on electricity pylons may cause short circuits when they become wet during periods of rain.
Each pair of birds builds its own chamber within these communal nests, in which the female lays a clutch of between two and six eggs that hatch after an incubation of about 14 days.
Sociable weavers are endemic to the southern African region, their distribution being limited to the arid north-western parts of South Africa and a large part of southern and central Namibia. Sociable weavers are mainly insectivorous, although they eat some seeds, and they do most of their foraging on the ground.
Their call is a series of metallic chipping sounds.
The scientific binomial for the Sociable weaver is Philetairus socius; Philetairus from the Latin for “loving friends and companions”, and socius from the Latin for “sociable”. Thus we have an extremely sociable bird, twice over!