Blue-billed Malimbe Malimbus nitens

Introduction

The Blue-billed Malimbe was formally described by George Robert Gray, an English zoologist, author, and head of the ornithological section of the British Museum. Gray started at the British Museum as Assistant Keeper of the Zoology Branch in 1831, when he would have found the specimen brought to the museum years earlier.The Blue-billed Malimbe had been collected by Captain Edward Sabine, an Irish astronomer, geophysicist, ornithologist, explorer, and soldier.

Sabine travelled halfway around the world to study the the “oblateness” (shape) of the Earth and carried out measurements on the intertropical coasts of Africa and the Americas. Sabine had struck up a friendship with Douglas Clavering, an officer of the British Royal Navy, who agreed to take Sabine on board the Pheasant. They travelled to Sierra Leone, the Island of St Thomas, Ascension Island, Bahia, Maranham, Trinidad, Jamaica, and New York during the years 1821-23.

The first illustration of a Blue-billed Malimbe is in Gray (1849), although it is a poor illustration (the original may be in colour, the internet scanned version is not). The next potential illustration is by Reichenbach (1863), who illustrated most weavers known at that time – he described 3 malimbes but the paintings of these species do not appear to have been published. This species was not illustrated again until Bannerman (1949).

Scientific citation

Ploceus nitens Gray 1831; Zool. Misc., 1, p.7; Sierra Leone (cf. Sharpe, 1890, Cat. Birds Brit. Mus., 13, p.481).

Meaning of names

nitens Latin: shining, glittering (nitere, to shine).

First English name

Red-breasted Weaver (Gray 1831).

Alternate names

Red-breasted Weaver, The shining Malimbus, Lake Albert Malimbe, Gray’s Blue-billed Weaver, Great Blue-billed Weaver.

Collector

Captain Edward Sabine.

Date collected

Between 1821 – 1823.

Locality collected

Sierra Leone.

Type specimens

One type specimen is in the British Museum (BM Old Vellum Cat. 21 no. 82a).

Identification. The Blue-billed Malimbe Malimbus nitens is black with a scarlet patch on the throat and upper breast (photo right, enlarged from phown 984). The blue bill is slightly curved. The female is similar to the male but is slightly duller, and the immature bird is browner with a dull orange patch.Distribution. The Blue-billed Malimbe is found from Senegal to western Uganda and northern Angola, as shown in the map (below, from Birds of Africa). It has no subspecies, although two were proposed in the past.

Habitat. The Blue-billed Malimbe inhabits primary, logged and mature old secondary lowland forest, keeping largely to the undergrowth. It is also found in riverine forest and dense thickets near water, or in swamp forest. The Blue-billed Malimbe is solitary or found in pairs or family parties.

Food. The Blue-billed Malimbe feeds on a wide variety of arthropods, including larvae, grubs, chrysalises, caterpillars, ants, hemipterans, grasshoppers, small beetles, butterflies and spiders. It sometimes feeds on seeds or oil palm fruits. It climbs tree limbs like a woodpecker, while foraging for arthropods.

Breeding. This species is monogamous and the male builds a new nest every season. Old nests may survive for several years so that a few nests may be clustered nearby. Sometimes several pairs form loose colonies. The nest is ball-shaped, made of strips of epiphytes, palm fibres, twigs and tendrils (see photo right, from Collias NE, Collias EC. 1964. Evolution of nest building in weaverbirds. Univ. Calif. Publ. Zool. 73:1-239). The nests often overhang forest rivers and ponds. The entrance tunnel is not very long, as in the nests of some malimbes.

The eggs are pale with darker markings, and incubation is by the female only.

A remarkable nesting association has been found in this species. They like to build their nests in the vicinity of dens of the Central African Dwarf Crocodile Osteolaemus tetraspis, presumably because the presence of crocodiles keeps predators away.

Breeding season
Jan-Jul in Senegal, Nov-Mar in Liberia, Jun-Mar in Ivory Coast, Jun-Jul and Sept-Oct in Ghana, Apr and Jul in Togo, Feb-Nov (mainly Apr-Jul) in Nigeria, May-Jun and Sept-Oct in Cameroon, Dec-Mar in Gabon; in all months except Apr and Aug in DRCongo, in Nov and Mar in Uganda, and Feb-Apr in Angola

Nest site
generally suspended from palm frond or small bush 0.4-3 m above forest stream or pool (one site abandoned when pool dried up), rarely in dry forest and then up to 10 m above ground

Nest building
built by male only

Colony size
Mostly solitary nester, and territorial; in Ghana also loose colonies of 5-21 nests (average 10 at six sites), with up to six of these occupied

Clutch size
2 eggs (average of 25 clutches)

Egg colour
whitish, grey, pale green or creamy-brown ground colour, large brown spots forming ring at thick end, sometimes salmon-pink with reddish spots (colour type apparently specific to individual females)

Egg size
average size of nine eggs 24.3 x 16.1 mm (Cameroon and DRCongo)

Incubation
incubation by female only, often absent from nest for extended periods, male perched nearby, gave alarm call when predators approached, incubation period 14 days

Chicks and nestling period
chicks fed by both sexes, nestling period 16 days