Strange Weaver Ploceus alienus

Weaver species list / RELATED SPECIES: Black-billed Weaver / Black-chinned Weaver / Black-necked Weaver / Clarke’s Weaver / Lesser Masked Weaver / Little Weaver / Loanga Weaver / Slender-billed Weaver / Spectacled Weaver / Strange Weaver / Tanganyika Masked Weaver

IUCN: Least concern Discovery: 102

Categories: fruit

Discovery

Strange Weaver, figure from Shelley (1905)
Strange Weaver
Strange Weaver egg (circled) figure from Ogilvie-Grant (1910)

Strange Weaver distribution, type locality circled

 

Introduction

The Strange Weaver was formally described by Richard Bowdler Sharpe, an English zoologist.The Strange Weaver was collected by Geoffrey Francis Archer, an English ornithologist, big game hunter and colonial official.

In 1901 the 19-year-old Archer joined his uncle Frederick John Jackson, the acting high commissioner in Uganda. His uncle sent him on an ornithological collecting trip in early 1902. Archer visited Lake Albert, the Semliki valley and the Rwenzori Mountains, discovering over twenty new species and subspecies. Four specimens of the Strange Weaver were collected in the Ruwenzori Mountains between 7 and 26 February. Archer noted that this weaver was common here. The specimens were sent to the British Museum.

The species was described later in the same year by Bowdler Sharpe as Sitagra aliena, where aliena means alien or strange. In fact, the English name for this species was Alien Weaver for several decades before becoming Strange Weaver. At this time there were many genera for the true weavers and Sharpe placed it in the genus Sitagra, which contained weavers with slender bills and black masks. However, this new species had a black head and throat, ie. the black area was much larger than a mask. His type description implies discussion with GE Shelley who thought this species best fit in with the Spectacled Weaver genus (Hyphanturgus), due to the slender bill and other similar characters. Either way, Sharpe considered it a strange weaver because it did not clearly fit into any weaver genus described in Shelley’s book (1905, The birds of Africa, comprising all the species which occur in the Ethiopian Region. Vol. 4, Part 2).

It has been claimed that “Sitagra aliena” was based on an anagram of Aline referring to Aline Jackson (nee Cooper), the aunt of Geoffrey Archer. However, “aliena” has an additional letter and thus is not an anagram. In Sharpe’s type description, he clearly mentioned the classification problem and thus could only have meant to name the species as “strange”.

The first illustration of the Strange Weaver was of the adult, published by Shelley (1905). The next illustration to be published 50 years later by Mackworth (1955).

Scientific citation

Sitagra aliena Sharpe 1902b, Bull. Br. Orn. Club 13 p.21, Ruwenzori, Uganda.

Meaning of names

alienus, Latin: alienus, strange, foreign.

First English name

Alien Weaver (Shelley 1905b).

Alternate names

Alien Weaver, Reichenbach’s Weaver.

Collector

Geoffrey Francis Archer.

Date collected

Feb 1902.

Locality collected

Ruwenzori, Uganda.

Type specimens

The types are in the British Museum.

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 [219] – Discovery [102]: Strange Weaver on 2016-08-24

1. Basic biology

Strange Weaver
Strange Weaver, figure from Shelley 1905b
Strange Weaver
Strange Weaver, figure from wikipedia

Identification. The Strange Weaver adult (photo above) has the head, neck and bib on the breast black, with a chestnut band below the bib. The female is similar but the black ends on the throat, and the breast is chestnut. Young birds are green above, yellow below, and with a golden brown wash on the chin and throat.

Distribution. The Strange Weaver occurs along the Albertine Rift in DR Congo, Uganda, Rwanda and Burundi (see map above, based on Birds of Africa).

No subspecies of the Strange Weaver are recognised.

Habitat. The Strange Weaver is a common understorey skulker in montane forest at 1500-2700 m. It generally forages in pairs low down in clearings, secondary growth and dense understorey usually below 5 m. It joins mixed-species flocks, associating particularly with Dark-backed Weavers.

Food. The Strange Weaver feeds on insects and invertebrates, and also eats berries and some seeds.

Breeding. The Strange Weaver is solitary and monogamous, probably having a permanent pair bond.

Strange Weaver
Strange Weaver nest, figure from PHOWN
Strange Weaver
Strange Weaver egg, figure from Ogilvie-Grant 1910b

The nest (photo above) is retort-shaped, with a short entrance tube pointing outwards, rather than straight down. Both sexes build the nest, primarily using thin tendrils of creepers, with some fine strips of grass. The coils of the short tendrils interlock. The nest is suspended from the tip of a branch 3-10 m above ground or over water. Branches near the nest are stripped of leaves and twigs. A pair may have 2 nests close together.The clutch size is 2. The eggs are creamy white with some grey shading, irregularly speckled with reddish-brown (figure above).

Old nests may be used for breeding by the White-collared Oliveback Nesocharis ansorgei.

The above is based on Weaver Wednesday, a weekly series about weaver species.
This species text first appeared as Weaver Wednesday [29]: Strange Weaver on 2013-01-02

2. Breeding facts

Pair bond
Monogamous, probably with long-term pair-bond


Breeding season
Jan-May, possibly throughout year, in DRCongo, and in Jan-Feb, Jun and Oct in Uganda


Nest site
suspended 3-10 m above ground from tip of branch


Nest building
built by both sexes


Colony size
Solitary nester, although one pair may have two nests close together


Clutch size
2 eggs


Egg colour
creamy white with some grey shading, irregularly spotted with reddish-brown


Egg size
average size of eight eggs 22.3 x 15 mm


Incubation
no information


Chicks and nestling period
no information


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

3. Photos of Weaver Nests


Vm 2896

Vm 2895

Vm 728

Thumb-nails of recent PHOWN records