Red-Billed Buffalo Weaver | Birding Uganda

Red-Billed Buffalo Weaver | Birding Uganda

Red-Billed Buffalo Weaver | Birding Uganda : This is a large, chunky thickest weaver species of bird with a length of 24cm. In addition, it weighs 65-80grams in the family Ploceidae nesting in the Eastern and Southern Africa. It mostly nests in dry savanna and sparse woodlands more so in acacia woodlands with scattered trees especially baobab trees. In fact, this bird derives its name from its habit of following an African buffalo, feeding on disturbing insects. The bird also derives its name ‘buffalo weaver’ from the Latin words “Niger” meaning “black” or shining black”. and “Bubalornis” meaning “Buffalo bird” and since red-billed buffalo weavers associated most with the buffaloes.

Description

The males have overall black plumage with a red vigorous vermilion bill, brown eyes. They have also got reddish brown feet, white wing tips and front wing edges. The females and the juveniles are pale brown streaky underneath, have paler bills and without white flecks on the wings. Her chin and throat feathers include broad white colored hems. During flight, the bird displays patches of striking white.  These birds forage on the ground in small to large groups, often in association with starlings and other birds in search for food.

Behaviours

The male red-billed buffalo weaver intends to be polygamous, colonial and dictate in nests. The nests are occupied from one to eight nest chambers with three females; in small groups or large flocks. Normally there’s one dominant male who controls the most chambers and the most females. On the other hand, males in lower social positions control fewer chambers and fewer females. The ruling males will always defend their chambers and females by showing aggressive displays and uttering out loud calls. As a matter of fact, females do not tolerate other females in their chambers during their nesting and when laying eggs. Females usually feed the chicks only if they are part of the cooperative breeding colony.

Breeding

The buffalo weavers are also known as the social birds, their breeding takes place in colonies. They usually breed in September to June with its peak being between December and March. Each female lays a clutch of 2-4 anomalous eggs, which she alone incubates for approximately 12 to 14days. After the 14 days, the chicks hatch and are chiefly fed by the females alone. However, males feed the young occasionally and later fledge after a period of 20 to 23 days.

Nesting

The nests are built on large trees especially baobabs and also man-made structures such as windmills, electricity pylons, etc. The nest is an enormous, bulky mass of interconnected thorny twigs divided into separate complexes. These include; lodges or compartments consisting of approximately 13 nesting chambers. Each every small nest is well-built by a female comprising of a ball of leaves, roots and grass.

The males build main structures and start lining chambers whilst the female adds further lining before laying. In case humans leave particular areas, the red-billed buffalo weaver immigrate and occupy in the same area. Bateleur eagles and white-backed vultures tend to construct their nests over or above the red-billed buffalo weaver nests. This is helpful in camouflaging or keeping away their nests from Predators. However, their nests can easily be recognized by their improper and messy construction.    

Reproduction

The male red-billed buffalo weaver possess a pseudo-penis with a length of 1.5cm. According to the continuous frequent researches it is proved that it is female selected. This penis has no blood vessels and does not carry sperms but rather appears to be favored by the females. In addition, dominant males in colonies possess larger pseudo-penises than the other males that live within the colony. This concludes that male to male competition has also favored the growth of this unusual organ. To attract females, the males hang from the downward-facing entrance and sway to-and-fro, flapping their wings and uttering swizzling calls until a female is attracted. Once she accepts the nest, she will then add the lining to the nest using dry grasses and leaves.

Foraging and feeding

The diet of this bird comprises of insects, seed as well as fruits. Specifically these weavers feed on caterpillars, locusts, grasshoppers, beetles, weevils, wasps, bees, ants, flies, spiders, etc. Most of these food sources are located in the soil or in low vegetation since more of its foraging is most carried out on the ground.

Where to find them in Uganda

In Uganda, the red-billed buffalo weaver can be found in national parks such as Murchison Falls National Park, Kidepo Valley National Park, etc.