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 Dean, W. R. J. (2005). Scaly-feathered Finch Sporopipes squamifrons. In Roberts Birds of Southern Africa. 7th edition (P. A. R. Hockey, W. R. J. Dean and P. G. Ryan, Editors), Trustees of the John Voelcker Bird Book Fund, Cape Town, South Africa. pp. 1005–1006. Close ) and Craig (3 Craig, A. J. F. K. (2010). Family Ploceidae (weavers). In Handbook of the Birds of the World, Volume 15: Weavers to New World Warblers (J. del Hoyo, A. Elliott, and D. A. Christie, Editors), Lynx Edicions, Barcelona, Spain. pp. 74–197. Close ), 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.

Natal Down

The nestling is covered with sparse grayish to silvery down (4 Mouritz, L. B. (1915). Notes on the ornithology of the Matopo District, Southern Rhodesia. Part II. Ibis 10(3):534-571. Close ). 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 Dean, W. R. J. (2005). Scaly-feathered Finch Sporopipes squamifrons. In Roberts Birds of Southern Africa. 7th edition (P. A. R. Hockey, W. R. J. Dean and P. G. Ryan, Editors), Trustees of the John Voelcker Bird Book Fund, Cape Town, South Africa. pp. 1005–1006. Close ), 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 Sinclair, I., P. Hockey, and W. Tarboton (1993). Birds of Southern Africa. New Holland, London, UK. Close ,2 Dean, W. R. J. (2005). Scaly-feathered Finch Sporopipes squamifrons. In Roberts Birds of Southern Africa. 7th edition (P. A. R. Hockey, W. R. J. Dean and P. G. Ryan, Editors), Trustees of the John Voelcker Bird Book Fund, Cape Town, South Africa. pp. 1005–1006. Close , 6 Chittenden, H., G. Davies, and I. Weiersbye (2016). Roberts Bird Guide. 2nd Edition. John Voelcker Bird Book Fund. Cape Town, RSA. Close ), while others note the malar stripes as indistinct (7 del Hoyo, J., A. Elliott, and D. A. Christie, Editors (2010). Handbook of the Birds of the World. Volume 15. Weavers to New World Warblers. Lynx Edicions, Barcelona, Spain. Close ), and thin malar stripes are illustrated by Peacock (8 Peacock, F. (2012). Chamberlain’s LBJs. The Definitive Guide to Southern Africa’s Little Brown Jobs. Mirafra Publishing, Pretoria, South Africa. Close ).

Formative Plumage

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.

Aberrant Plumages

Two leucistic individuals have been recorded; one in Namibia with no details (9 Thomson, N. (2022). Rarities and Interesting Sightings. Lanioturdus 55(1):28-35. Close ), 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 Hoets, D. (1988). Atlas news. Hadeda 8:15-17. Close ).

Molt and plumage terminology follow Humphrey and Parkes (11 Humphrey, P. S., and K. C. Parkes (1959). An approach to the study of molts and plumages. Auk 76(1):1–31. Close ), as modified by Howell et al. (12 Howell, S. N. G., C. Corben, P. Pyle, and D. I. Rogers (2003). The first basic problem: a review of molt and plumage homologies. Condor 105:635–653. Close ). 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 Jenni, L., and R. Winkler (2020). Moult and Ageing of European Passerines. Second edition. Bloomsbury, London, UK. Close ; see also 14 Pyle, P. (2022). Defining moults in migratory birds: a sequence-based approach. Journal of Avian Biology 2022(5):e02958. Close ). The Scaly Weaver appears to show a Complex Basic Molt strategy (see 12 Howell, S. N. G., C. Corben, P. Pyle, and D. I. Rogers (2003). The first basic problem: a review of molt and plumage homologies. Condor 105:635–653. Close ), with Complete Preformative and Definitive Prebasic molts, but no Prealternate Molts (15 Tyler, S. J. (2001). Moult in Scalyfeathered Finches Sporopipes squamifrons in southeast Botswana. Afring News 30:56-59. Close ). 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 Tyler, S. J. (2001). Moult in Scalyfeathered Finches Sporopipes squamifrons in southeast Botswana. Afring News 30:56-59. Close ), and in northern Botswana, all birds examined in late January were replacing primaries (16 Traylor, M. A. (1965). A collection of birds from Barotseland and Bechuanaland. Ibis 107:137-172. Close ). Similarly, all birds examined in late February in the Northern Cape were in molt, as was one in late August (17 Liversidge, R. (1968). Bird weights. Ostrich 39:223–227. Close ). One of 6 breeding birds collected at Marble Hall, Limpopo Province, in January, was molting body and some flight feathers (18 Payne, R. B. (1969). Overlap of breeding and molting schedules in a collection of African birds. Condor 71:140-145. Close ). 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 Payne, R. B. (1969). Overlap of breeding and molting schedules in a collection of African birds. Condor 71:140-145. Close ) - 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 Tyler, S. J. (2001). Moult in Scalyfeathered Finches Sporopipes squamifrons in southeast Botswana. Afring News 30:56-59. Close ). Molts can frequently be suspended (15 Tyler, S. J. (2001). Moult in Scalyfeathered Finches Sporopipes squamifrons in southeast Botswana. Afring News 30:56-59. Close ), perhaps for breeding, when conditions for reproduction become favorable, as has been recorded in other passerines that can undergo year-round breeding (19 Pyle, P., K. Tranquillo, K. Kayano, and N. Arcilla (2016). Molt patterns, age criteria, and molt-breeding dynamics in American Samoan landbirds. Wilson Journal of Ornithology 128(1):56–69. Close ). Tyler (15 Tyler, S. J. (2001). Moult in Scalyfeathered Finches Sporopipes squamifrons in southeast Botswana. Afring News 30:56-59. Close ) 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 Tyler, S. J. (2001). Moult in Scalyfeathered Finches Sporopipes squamifrons in southeast Botswana. Afring News 30:56-59. Close ). 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 Tyler, S. J. (2001). Moult in Scalyfeathered Finches Sporopipes squamifrons in southeast Botswana. Afring News 30:56-59. Close ).

Bill

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 Craig, A. J. F. K. (2010). Family Ploceidae (weavers). In Handbook of the Birds of the World, Volume 15: Weavers to New World Warblers (J. del Hoyo, A. Elliott, and D. A. Christie, Editors), Lynx Edicions, Barcelona, Spain. pp. 74–197. Close ). 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 Dean, W. R. J. (2005). Scaly-feathered Finch Sporopipes squamifrons. In Roberts Birds of Southern Africa. 7th edition (P. A. R. Hockey, W. R. J. Dean and P. G. Ryan, Editors), Trustees of the John Voelcker Bird Book Fund, Cape Town, South Africa. pp. 1005–1006. Close ), 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 da Rosa Pinto, A. A. (1967). Descrição de 4 novas subespécies de aves de Angola. Boletim do Instituto de Investigação Científica de Angola 4:29-32. Close ), but sample sizes are small, and these differences may not be real. The measurements given below are from three sources: Dean (2 Dean, W. R. J. (2005). Scaly-feathered Finch Sporopipes squamifrons. In Roberts Birds of Southern Africa. 7th edition (P. A. R. Hockey, W. R. J. Dean and P. G. Ryan, Editors), Trustees of the John Voelcker Bird Book Fund, Cape Town, South Africa. pp. 1005–1006. Close ) gives a summary from various sources and represents data from across the species range, Rose and colleagues (21 Rose, S., R. L. Thomson, H-D. Oschadleus, and A. T. K. Lee (2020). Summarising biometrics from the SAFRING database for southern African birds. Ostrich 91(2):169–173. Close ) 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 Paijmans, D., and U. Bryson (2023). A comparison of measurements of passerine species and subspecies in Namibia. Afrotropical Bird Biology 3:1–69. Close ) summarised biometric data collected in Namibia only, representing the nominate subspecies.

Linear Measurements

Total Length

Unsexed 100–110 mm (2 Dean, W. R. J. (2005). Scaly-feathered Finch Sporopipes squamifrons. In Roberts Birds of Southern Africa. 7th edition (P. A. R. Hockey, W. R. J. Dean and P. G. Ryan, Editors), Trustees of the John Voelcker Bird Book Fund, Cape Town, South Africa. pp. 1005–1006. Close )

Bill Length

• 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 Dean, W. R. J. (2005). Scaly-feathered Finch Sporopipes squamifrons. In Roberts Birds of Southern Africa. 7th edition (P. A. R. Hockey, W. R. J. Dean and P. G. Ryan, Editors), Trustees of the John Voelcker Bird Book Fund, Cape Town, South Africa. pp. 1005–1006. Close ).
• Unsexed adults 11.1 mm ± 6.90 SD (no range given, n = 472) (21 Rose, S., R. L. Thomson, H-D. Oschadleus, and A. T. K. Lee (2020). Summarising biometrics from the SAFRING database for southern African birds. Ostrich 91(2):169–173. Close ).
• 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 Paijmans, D., and U. Bryson (2023). A comparison of measurements of passerine species and subspecies in Namibia. Afrotropical Bird Biology 3:1–69. Close ).
• Adult male " S. s. pallidus" in Angola, 11 mm for male type specimen (20 da Rosa Pinto, A. A. (1967). Descrição de 4 novas subespécies de aves de Angola. Boletim do Instituto de Investigação Científica de Angola 4:29-32. Close ).

Wing Length

• 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 Dean, W. R. J. (2005). Scaly-feathered Finch Sporopipes squamifrons. In Roberts Birds of Southern Africa. 7th edition (P. A. R. Hockey, W. R. J. Dean and P. G. Ryan, Editors), Trustees of the John Voelcker Bird Book Fund, Cape Town, South Africa. pp. 1005–1006. Close ).
• 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 Rose, S., R. L. Thomson, H-D. Oschadleus, and A. T. K. Lee (2020). Summarising biometrics from the SAFRING database for southern African birds. Ostrich 91(2):169–173. Close ).
• 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 Paijmans, D., and U. Bryson (2023). A comparison of measurements of passerine species and subspecies in Namibia. Afrotropical Bird Biology 3:1–69. Close ).
• Adult male 52–57 mm, n = 11, and adult female 51–57 mm, n = 4, for "S. s. pallidus" in Angola (20 da Rosa Pinto, A. A. (1967). Descrição de 4 novas subespécies de aves de Angola. Boletim do Instituto de Investigação Científica de Angola 4:29-32. Close ).

Tail Length

• 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 Dean, W. R. J. (2005). Scaly-feathered Finch Sporopipes squamifrons. In Roberts Birds of Southern Africa. 7th edition (P. A. R. Hockey, W. R. J. Dean and P. G. Ryan, Editors), Trustees of the John Voelcker Bird Book Fund, Cape Town, South Africa. pp. 1005–1006. Close ).
• 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 Rose, S., R. L. Thomson, H-D. Oschadleus, and A. T. K. Lee (2020). Summarising biometrics from the SAFRING database for southern African birds. Ostrich 91(2):169–173. Close ).
• 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 Paijmans, D., and U. Bryson (2023). A comparison of measurements of passerine species and subspecies in Namibia. Afrotropical Bird Biology 3:1–69. Close ).
• Adult male 34–36 mm, n = 11, and adult female 31–35 mm, n = 4, for "S. s. pallidus" in Angola (20 da Rosa Pinto, A. A. (1967). Descrição de 4 novas subespécies de aves de Angola. Boletim do Instituto de Investigação Científica de Angola 4:29-32. Close ).

Tarsus Length

• 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 Dean, W. R. J. (2005). Scaly-feathered Finch Sporopipes squamifrons. In Roberts Birds of Southern Africa. 7th edition (P. A. R. Hockey, W. R. J. Dean and P. G. Ryan, Editors), Trustees of the John Voelcker Bird Book Fund, Cape Town, South Africa. pp. 1005–1006. Close ).
• Unsexed adults 17.6 mm ± 22.20 SD (no range given, n = 319) (21 Rose, S., R. L. Thomson, H-D. Oschadleus, and A. T. K. Lee (2020). Summarising biometrics from the SAFRING database for southern African birds. Ostrich 91(2):169–173. Close ).
• 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 Paijmans, D., and U. Bryson (2023). A comparison of measurements of passerine species and subspecies in Namibia. Afrotropical Bird Biology 3:1–69. Close ).
• Adult male "S. s. pallidus" in Angola, 15 mm for male type specimen (20 da Rosa Pinto, A. A. (1967). Descrição de 4 novas subespécies de aves de Angola. Boletim do Instituto de Investigação Científica de Angola 4:29-32. Close ).

Mass

• 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 Dean, W. R. J. (2005). Scaly-feathered Finch Sporopipes squamifrons. In Roberts Birds of Southern Africa. 7th edition (P. A. R. Hockey, W. R. J. Dean and P. G. Ryan, Editors), Trustees of the John Voelcker Bird Book Fund, Cape Town, South Africa. pp. 1005–1006. Close ).
• 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 Rose, S., R. L. Thomson, H-D. Oschadleus, and A. T. K. Lee (2020). Summarising biometrics from the SAFRING database for southern African birds. Ostrich 91(2):169–173. Close ).
• 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 Paijmans, D., and U. Bryson (2023). A comparison of measurements of passerine species and subspecies in Namibia. Afrotropical Bird Biology 3:1–69. Close ).