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Proud

One explanation for why females favour long tails in male long-tailed widowbirds is that the expanded tail enlarges the lateral surface area of the male by 2–3 times, making him much more visible from far distances over open grassland. However, this is most likely not the whole explanation, especially considering that prior to mating, females spend a great deal of time comparing males and, thus, do not rely on sighting them from a distance. As of this time, the exact function of epaulette in male long-tailed widowbirds is unknown. However, its use does resemble that of the red-winged blackbird, being displayed during courtship and threat displays. Thus, the two most conspicuous ornaments of the male birds in the two species may be favoured by different forms of sexual selection: the tail of the long-tailed widowbird by female choice and the brightly coloured epaulettes of the long-tailed widowbird and red-winged blackbird by male contest competition.

27 November 2018Picture of the day, Wildlife

Hidden

Although weavers are named for their elaborately woven nests, some are notable for their selective parasitic nesting habits instead. The nests vary in size, shape, the material used, and construction techniques from species to species. Materials used for building nests include fine leaf fibres, grass, and twigs. Many species weave very fine nests using thin strands of leaf fibre, though some, like the buffalo-weavers, form massive untidy stick nests in their colonies, which may have spherical woven nests within. The sociable weavers of Africa build apartment-house nests, in which 100 to 300 pairs have separate flask-shaped chambers entered by tubes at the bottom. The sparrow weavers live in family units that employ cooperative breeding. Most species weave nests that have narrow entrances, facing downward. Many weaver species are gregarious and breed colonially. The birds build their nests together for protection, often several to a branch. Usually, the male birds weave the nests and use them as a form of display to lure prospective females.

26 November 2018Picture of the day, Wildlife

Disordered

The African Gray Hornbill prefers open woodland and savannah. The female lays two to four white eggs in a tree hollow, which is blocked off during incubation with a cement made of mud, droppings and fruit pulp. There is only one narrow aperture, just big enough for the male to transfer food to the mother and the chicks. When the chicks and female outgrow the nest, the mother breaks out and rebuilds the wall, after which both parents feed the chicks. The male has a black bill, whereas the female has red on the mandibles. The plumage of the male and female is similar. Immature birds are more uniformly grey. The flight is undulating. The similarly sized red-billed hornbill has uniformly grey plumage.
The African grey hornbill is omnivorous, taking insects, fruit and reptiles. It feeds mainly in trees.

23 November 2018Picture of the day, Wildlife