Species names in all available languages
|English (South Africa)||Scaly-feathered Finch|
|English (United States)||Scaly Weaver|
|French (French Guiana)||Sporopipe squameux|
|Russian||Усатый воробьиный ткачик|
|Spanish (Spain)||Tejedorcito escamoso|
|Turkish||Pul Alınlı Dokumacı|
This account is part of the 8th edition of Roberts Birds of Southern Africa. This project is a joint collaboration between the John Voelcker Bird Book Fund and the Cornell Lab of Ornithology. H. Dieter Oschadleus revised the account. Peter Pyle contributed to the Plumages, Molts, and Structure page. Shawn M. Billerman contributed to the Systematics page. Arnau Bonan Barfull curated the media. Huy C. Truong updated the distribution map.
Sporopipes squamifrons ("Smith, A", 1836)
The Key to Scientific Names
Scaly Weaver Sporopipes squamifrons Scientific name definitions
Version: 2.0 — Published February 23, 2023
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Plumages, Molts, and Structure
The Scaly Weaver has 10 primaries (numbered distally, from innermost p1 to outermost p10, with p10 reduced in length), 9 secondaries (numbered proximally, from outermost s1 to innermost s9, and including 3 tertials, s7‒s9 in passerines), and 12 rectrices (numbered distally, from innermost r1 to outermost r6 on each side of the tail). The following plumage descriptions are based on those of Hockey et al. (2) and Craig (3), along with the examination of Macaulay Library images. See Molts for molt and plumage terminology. Definitive (adult) appearance is usually attained after the Preformative Molt (and definitive plumage after the second Prebasic Molt). Sexes appear to be similar in all plumages.
The nestling is covered with sparse grayish to silvery down (4). See Breeding: Young Birds for more detail.
Juvenile (First Basic) Plumage
Juvenile Plumage is similar to Definitive Basic Plumage except it averages duller, the head pattern with less distinct and browner lores and malar stripes (not absent, as indicated in 2), and lacking the scaling on the forehead, the feathering here instead being dull gray-brown (see photo by Louise Victor [www.louisevictorphotography.co.za]). Feathering to the underparts is more filamentous due to lower barb densities. Some references indicate that the juvenile has no malar stripes (5,2, 6), while others note the malar stripes as indistinct (7), and thin malar stripes are illustrated by Peacock (8).
Formative Plumage appears to be inseparable from Definitive Basic Plumage following complete Preformative Molt. Some individuals appear to suspend molts (see Molts) and in other weavers the Preformative Molt can occasionally be incomplete, with, e.g., s5–s6 retained. In such cases, Formative Plumage can be identified; further study is needed.
Definitive Basic Plumage
Forehead and crown feathers are black with arrow-shaped white margins (see ); the side of the head, nape, and upperparts are dull gray-brown. The tail is dark brown to blackish with white edges to the rectrices. The upperwing is brown (grayish-black in fresh plumage) with contrastingly blackish-brown upperwing coverts and tertials, with broad white margins. The chin and lores are black, and the throat white, with two distinct black malar streaks extending down the throat, bordered above by a white stripe. It has a distinct white eye-ring. The underparts are whitish to pale buff, often with a pale brown wash on the breast.
Two leucistic individuals have been recorded; one in Namibia with no details (9), the other record was seen in the Polokwane area and was described as the feathers on the front and back being snow white, and the scales were black (10).
Molt and plumage terminology follow Humphrey and Parkes (11), as modified by Howell et al. (12). Under this nomenclature, terminology is based on evolution of molts along ancestral lineages of birds from ecdysis (molts) of reptiles, rather than on molts relative to breeding season, location, or time of the year, the latter generally referred to as “life-cycle” molt terminology (13; see also 14). The Scaly Weaver appears to show a Complex Basic Molt strategy (see 12), with Complete Preformative and Definitive Prebasic molts, but no Prealternate Molts (15). See Breeding: Young for details on the Prejuvenile Molt, which occurs in the nest.
In southeastern Botswana, molt of primaries was recorded in all months except April and May (no birds were examined in May; 15), and in northern Botswana, all birds examined in late January were replacing primaries (16). Similarly, all birds examined in late February in the Northern Cape were in molt, as was one in late August (17). One of 6 breeding birds collected at Marble Hall, Limpopo Province, in January, was molting body and some flight feathers (18). Timing of molt appears to be quite variable, as suggested by variable and year-round breeding seasonality (see Breeding: Phenology). One female, of four females that were incubating eggs in January, also was undergoing a complete molt (18) - this is the only example of overlap of breeding and molt in this species, although it may be expected to happen regularly given the opportunistic breeding of this species in response to favorable environmental conditions (see Breeding: Phenology).
During Preformative and Prebasic molts, primaries are most often replaced distally (from p1 to p10), secondaries are replaced bidirectionally from the middle tertial (s8) and proximally from s1 such that the last feather replaced is s5 or s6, and rectrices are generally replaced distally from the central r1 to the outer r6 on each side of the tail (15). Molts can frequently be suspended (15), perhaps for breeding, when conditions for reproduction become favorable, as has been recorded in other passerines that can undergo year-round breeding (19). Tyler (15) recorded irregular molt sequences in 21.6% of individuals, which may have resulted from molts being suspended and reactivated at various locations; it is possible that molts can also arrest or even that more than one wave can occur as in species exhibiting Staffelmauser or stepwise molt; study needed. Primary molt duration was reported to last at least 200 days, and up to 350 days, but this likely included suspended molts (15). In other weavers, the Preformative Molt may occasionally be incomplete, with one to a few flight feathers retained. This occurs mostly among s5 and s6, and may be anticipated in the Scaly Weaver, a species with frequent suspension of molt (15).
The bill is dusky or horn-yellow in nestlings, becoming dull pink in juveniles and during the first year. In adults, the bill is bright rose pink with the base of lower mandible pale bluish-gray (3). See images under Plumages.
Iris and Facial Skin
Eyes are dark brown to reddish brown with a narrow white eye ring.
Tarsi and Toes
Legs and feet are pinkish-brown to grayish-brown (2), perhaps brighter and pinker in breeding adults than in juveniles and non-breeding birds. Needs study.
Angolan birds, representing the nominate subspecies, Sporopipes squamifrons, squamifrons, appear to be slightly smaller than those in Namibia (20), but sample sizes are small, and these differences may not be real. The measurements given below are from three sources: Dean (2) gives a summary from various sources and represents data from across the species range, Rose and colleagues (21) summarized data in the SAFRING database collected by various registered bird ringers and also includes data from across the species' range, while Bryson and Paijmans (22) summarised biometric data collected in Namibia only, representing the nominate subspecies.
Unsexed 100–110 mm (2)
- Adult male 10.9 mm (range 10.5–11.3, n = 12); Adult female 11.2 mm (range 10.5–12.0, n = 14) (2).
- Unsexed adults 11.1 mm ± 6.90 SD (no range given, n = 472) (21).
- Adult male 12.7 mm (n = 1); Adult female 12.4 mm ± 1.40 SD (range: 10.0–15.0, n = 9); unsexed adults 12.0 g ± 1.01 SD (range 9.0–14.0, n = 32) (22).
- Adult male " S. s. pallidus" in Angola, 11 mm for male type specimen (20).
- Adult male 57.6 mm (range 55.0–60.0, n = 21); Adult female 56.3 mm (range 52.0–59.0, n = 29) (2).
- Adult male 57.9 mm ± 1.70 SD (no range given, n = 85); Adult female 56.5 mm ± 1.90 SD (no range given, n = 201). Wing significantly longer in males than females (p < 0.001) (21).
- Adult male 57.9 mm ± 1.35 SD (range 55.0–63.0, n = 58); Adult female 56.7 mm ± 1.62 SD (range: 51.0–61.0, n = 117); unsexed adults 56.7 mm ± 2.19 SD (range 49.0–72.0, n = 238) (22).
- Adult male 52–57 mm, n = 11, and adult female 51–57 mm, n = 4, for "S. s. pallidus" in Angola (20).
- Adult male 40.0 mm (range 37.0–42.0, n = 12); Adult female 39.9 mm (range 36.0–42.0, n = 14) (2).
- Adult male 39.9 mm ± 1.50 SD (no range given, n = 64); Adult female 39.0 mm ± 1.90 SD (no range given, n = 140). Tail significantly longer in males than females (p = 0.001) (21).
- Adult male 40.0 mm ± 1.49 SD (range 37.0–44.0, n = 52); Adult female 39.1 mm ± 1.71 SD (range: 35.0–44.0, n = 109); unsexed adults 39.4 mm ± 2.38 SD (range 30.0–52.0, n = 188) (22).
- Adult male 34–36 mm, n = 11, and adult female 31–35 mm, n = 4, for "S. s. pallidus" in Angola (20).
- Adult male 15.7 mm (range 14.7–16.5, n = 12); Adult female 15.9 mm (range 14.6–16.6, n = 14) (2).
- Unsexed adults 17.6 mm ± 22.20 SD (no range given, n = 319) (21).
- Adult male 15.9 (n = 1); Adult female 15.0 mm ± 0.29 SD (range: 14.6–15.5, n = 8); unsexed adults 15.2 mm ± 0.56 SD (range 14.0–16.1, n = 32) (22).
- Adult male "S. s. pallidus" in Angola, 15 mm for male type specimen (20).
- Adult male 11.3 g (range 8.5–13.0, n = 12); Adult female 10.9 g (range: 10.0–12.0, n = 9); unsexed adults 11.9 g (range 8.9–13.7, n = 85) (2).
- Adult male 12.9 g ± 7.80 SD (no range given, n = 125); Adult female 13.2 g ± 11.20 (no range given, n = 232). No significant difference in mass of males and females (p = 0.175) (21).
- Adult male 11.0 g ± 0.72 SD (range 9.2–12.7, n = 70); Adult female 11.2 g ± 0.93 SD (range: 9.4–13.8, n = 124); unsexed adults 11.0 g ± 0.78 SD (range 6.5–13.2, n = 270) (22).