Tropical Boubou

The Tropical Boubou, or Bell Shrike (Laniarius aethiopicus), is a medium-sized passerine bird, a member of the bushshrike family. It is a robust bird, with a length of 23–25 cm and a weight ranging from 38-70 g, though most adults tip the scales between 50 and 60 g. The sexes are similar in size and plumage, which is a glossy blue-black on the upper parts and tail, with a white underbelly. Some populations may exhibit a buffy or pinkish tinge on the breast and flanks. A white stripe adorns the wings of most subspecies, and the bill is black, with legs and feet of a bluish-grey hue. The irides are a dark reddish-brown.

Identification Tips

Adults can be identified by their blue-black upper parts and white underparts, with a white stripe on the wing coverts. The bill's length may vary between subspecies. Nestlings are initially pinkish-brown and nude, while fledglings resemble adults but are duller with mottled brown heads. Immature birds lose most of their mottling and have a dull white underside.

Habitat

The Tropical Boubou is found in a variety of forest and forest-edge habitats, including savannah, Miombo woodland, and village gardens. It prefers dense ground cover and is typically found in regions with vegetation like African juniper, bracken, and Rosoideae shrubs.

Distribution

This species is distributed across sub-Saharan Africa, from about 10° northern latitude south to the Limpopo River in South Africa. It is not migratory but may move locally, with seasonal movements known from Kenya.

Behaviour

The Tropical Boubou is territorial, defending a breeding territory of 1–3 hectares. It is more tolerant of conspecifics outside the breeding season, sometimes forming loose groups. The bird is adept at skulking in shrubs and tends to stay low in trees or on the ground, making short flights when alarmed.

Song & Calls

The Tropical Boubou's vocal repertoire is extensive, including duets where two individuals alternate notes rapidly. Calls range from loud, high-pitched 'bou' or 'boubou' to lower, softer sounds for maintaining contact. Alarm calls are chattering outbursts, and a variety of other calls are used in different social interactions.

Breeding

Monogamous by nature, the Tropical Boubou does not have a pronounced breeding season near the Equator, but further from it, breeding peaks in late spring and early summer. Courtship involves chasing, hopping, and display flights. The nest is a flimsy cup built by both parents, placed at varying heights, and the female lays two to three eggs.

Similar Species

The Tropical Boubou can be confused with Turati's Boubou and the Swamp Boubou, but differences in plumage and calls can help distinguish them. Hybridization with the Southern Boubou has been observed in the Limpopo valley.

Diet and Feeding

The diet consists of terrestrial invertebrates, small vertebrates, and occasionally fruit. The bird forages on or near the ground and is known to impale prey on thorns or wedge it into crevices for later consumption.

Conservation Status

The IUCN lists the Tropical Boubou as Least Concern. However, with recent taxonomic splits, some of the newly recognized species with limited ranges might warrant uplisting.