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Thursday 3 December 2015

26-11-2015 JURONG, SINGAPORE - SUPERB STARLING (Lamprotornis superbus)


The breeding season lasts from October to February in Ethiopia, from March to June in Somalia. Superb starlings have been observed running on the ground, jumping with drooping wing and outstretched heads, indicating what is thought to be a form of nuptial display.

Free-standing nests are constructed in thorn trees bushes, although there have been reports of nests in tree holes and even cliffs or rock crevices. The nests in the thorn trees are positioned at 1.5–6 metres (4.9–19.7 ft) above the ground and are well guarded by the thorns. They also sometimes nest at the base of raptor nests for protection. The superb starlings make their own nests, and both sex help with the nests, which are large structures made of twigs lined with dry grass, featuring an entrance on one side. On occasion, they can take over nests belonging to White-headed Buffalo Weavers (Dinemellia dinemelli), sometimes rejecting the existing eggs.


Superb starlings’ eggs are uniformly dark blue, measuring 24–26 millimetres (0.94–1.02 in) x 18–19 millimetres (0.71–0.75 in) and weighting 4.5 g. Females lay 3-4 eggs. Based on captive breeding, the incubation period lasts 12-13 days, and the surprisingly short nestling period ranges from 18-24 days. Only the females incubate. Nestlings are fed insects, primarily caterpillars and grasshoppers. Superb starlings form large social groups in which both breeding parents and 1-14 alloparents contribute to the care of the offspring. It appears that both members of the breeding pair are involved in raising the young until they achieve independence. The individuals who’s provisioned or nestled has been observed carrying food in their bills and did not seem to regurgitate. Starlings lack a crop and may lack a mechanism to prevent digestion of food items in transit. Consequently, they might be compelled to transport insects in their bills to avoid damaging such easily digested prey.


In superb starlings, individuals of both sexes can either choose to forego dispersal (remaining residents of their birth group) or become immigrants (leaving their birth group). Immigrants, being unrelated to the resident individuals of the group they join, may experience ongoing conflict with the residents throughout their lives. Resident females never breed within their natal groups. Both resident and immigrant males have to opportunity to attain breeding status within the same social group during a breeding season. Indeed, despite the presence of reproductively capable resident males and unrelated potential mates, immigrant males often seize breeding opportunities within their new social groups. Apart from the potential inclusive fitness benefit gained by assisting in raising their offspring, superb starlings also benefit from being social on the group and individual levels. Living in larger social groups enhances an individual’s chances of survival and reduces reproductive variance within the group. This is likely because larger predators are actively confronted by the group, with a greater resource availability in the territories inhabited by larger groups.

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