Bertram’s Weaver Ploceus bertrandi

Weaver species list / RELATED SPECIES: Baglafecht Weaver / Bannerman’s Weaver / Bertram’s Weaver / Giant Weaver / Orange Weaver / Principe Golden Weaver / Vieillot’s Black Weaver / Weyns’s Weaver

IUCN: Least concern Discovery: 093

Categories: acacias, nectar, palm

Discovery

Bertram’s Weaver, figure from Shelley (1893)

 

Bertram’s Weaver distribution, type locality circled

Introduction

Bertram’s Weaver was formally described by George Ernest Shelley, an English geologist and ornithologist.Bertram’s Weaver was collected by Alexander Whyte, a Scottish botanist.

Commissioner HH Johnston hired Alexander Whyte to collect fauna and flora specimens in British Central Africa. Bertram Lutley Sclater, the son of the ornithologist Dr. P. L. Sclater, and Commander of the Police Force of British Central Africa 1891-93, accompanied the expedition as security.

Whyte collected birds in 3 localities in southern Malawi in 1891. On 29 May they ascended Mt Zomba, then collected specimens here during Aug-Sep, including two Bertram’s Weaver specimens. On 20 Oct the expedition visited Mt Milanji spending 2 weeks on the plateau, collecting one Bertram’s Weaver specimen.

Whyte also collected several female Bertram’s Weaver specimens in southern Malawi during 1892. These were also investigated by Shelley (in 1894) who described them as males of a separate species. A few decades later, Neunzig 1924a realised that these were the female of Bertram’s Weaver, based on a large sample of specimens of both taxa in the Berlin Museum.

Shelley named Bertram’s Weaver after Bertram Lutley Sclater, but the scientific name was given as bertrandi rather than as bertrami.

The first illustration of Bertram’s Weaver was of a male and juvenile, published by Shelley (1893) in his initial description of the species. The next illustration was of the female of this species in Shelley (1905), initially thought to be the male of a different species.

 

Scientific citation

Hyphantornis bertrandi Shelley 1893a, Ibis, p.23, pl. 2, Plains near Milanji, southern Nyasaland [Zomba].

Meaning of names

bertrandi, Named after Captain Bertrand L. Sclater (1866-1897).

First English name

Nyasa Black-beaded Weaver (Shelley 1905b).

Alternate names

Bertrand’s Weaver, Bertrand’s Masked-Weaver, Nyasa Black-beaded Weaver.

Collector

Alexander Whyte.

Date collected

Aug, Sep, Oct 1891.

Locality collected

Milanji (Mount Mulanje) and Zomba, Malawi.

Type specimens

Three syntypes are in the British Museum (eg BM 1892.9.10.181).

The above is based on Weaver Wednesday 2, a weekly series about the discovery of each weaver species.
This species text first appeared as Weaver Wednesday [210] – Discovery [93]: Bertram’s Weaver on 2016-06-22

1. Basic biology


Male


Female

Identification. Bertram’s Weaver male is distinctive, with a chestnut crown, a black nape patch that is separated from the black face and throat by a narrow yellow line; it is golden yellow below with a saffron wash on the neck and breast. The female has an all-black head. Both sexes have yellow eyes, and unstreaked upperparts. The juvenile is similar to the female but the black on the head is mixed with green and yellow. Sympatric forms of the Baglafecht Weaver P. baglafecht also have yellow eyes and a black mask, but the throat is yellow, and the upperparts are streaked.
Distribution. Bertram’s Weaver occurs in eastern Africa, from Tanzania, through Zambia and Malawi to Mozambique (see map below, based on Birds of Africa). No subspecies are recognised.Bertram's Weaver map
Habitat. Bertram’s Weaver inhabits open woodland and bush along rivers, forest edges and cultivation in hilly country. It is found in trees and bracken-briar along stream lines in Zambia.
Food. Bertram’s Weaver feeds on insects and nectar. It forages in pairs and in small groups of five or six individuals, by gleaning insects from vegetation.
Breeding. Bertram’s Weaver is a monogamous, solitary nester. The nest is a ball woven of broad grass strips, without an entrance tunnel. The nest resembles the nest of the Holub’s Golden Weaver, but is rounder. The nest is lined with grass seed heads. It is typically placed near the tip of a lower branch of camelthorn acacias, or in the leafy end of an evergreen tree branch, and often near a stream.The eggs (clutch size 2) are deep green, heavily blotched and spotted with red-brown. The young fed by both sexes.

The above is based on Weaver Wednesday, a weekly series about weaver species.
This species text first appeared as Weaver Wednesday [80]: Bertram’s Weaver on 2013-12-25

2. Breeding facts

Pair bond
Monogamous

Breeding season
Apr in Tanzania, Nov-Dec in Zambia and Aug-Apr (also record of fledged young fed by adults in May) in Malawi

Nest site
usually placed at tip of branch of thorny acacia (Acacia) or in evergreen tree, often near a stream

Nest building
no information

Colony size
Solitary nester

Clutch size
2 eggs

Egg colour
deep green, heavily marked with red-brown spots and blotches

Egg size
size 22.5 x 16 mm (Malawi)

Incubation
no information

Chicks and nestling period
young fed by both sexes

Breeding information based on Handbook of the Birds of the World, Vol. 15.

3. Photos of Weaver Nests

No records yet – be the first to submit a PHOWN record!