20-4-2024 BANDHAVGARH, INDIA - WHITE BELLIED DRONGO (Dicrurus caerulescens)

The white-bellied drongo (Dicrurus caerulescens ) is a species of drongo found across the Indian Subcontinent. Like other members of the family Dicruridae, they are insectivorous and mainly black in colour, but with a white belly and vent. Young birds are, however, all black and may be confused with the black drongo, which is smaller and more compact in appearance. The subspecies found in Sri Lanka has white restricted to the vent.

This drongo is black without any glossy feathers on the upperside and greyish on the throat and breast, while the belly and vent are entirely white in the Indian form which is the nominate subspecies. The fork of the tail is less deep than in the black drongo which is often seen in the same habitats. Young black drongo's can have a lot of white on the underside but it is usually scaly in appearance. The Sri Lankan forms insularis of the northern dry zone and leucopygialis of the southern wet zone have the white restricted to the vent. Birds that are less than a year old lack the white on the underside but are browner above and greyish below. Males have a very slightly shorter tail on average than females.

The size of the birds varies clinally with northern birds larger. The extent of white on the underside also declines with size although there is a lot of local variation. The Sri Lankan forms leucopygialis and insularis are darker than the Indian form and there is some intergradation within the Sri Lankan forms.The species is believed to be closely related to Dicrurus leucophaeus but has not be confirmed with molecular sequence studies.

Both the white-bellied drongo and the black drongo share a diploid chromosome number of 68.

The white-bellied drongo is a resident breeder in India and Sri Lanka. This species is usually found in dry scrub or open forests. The distribution is restricted to peninsular India south of the Himalayas and to the west of the Gangetic delta bounded on the west by the Aravallis.