African Silverbill

The African Silverbill (Euodice cantans) is a small passerine bird native to the dry savanna regions south of the Sahara Desert in Africa. This species, once considered conspecific with the Indian Silverbill (Euodice malabarica), is now recognized as a distinct species. Known for its delicate appearance and pleasant song, the African Silverbill has also been introduced to several countries outside its native range.

The African Silverbill is a small, finch-like bird, measuring approximately 10 cm (3.9 inches) in length and weighing between 8-10 grams. Its most distinctive features include a stubby silver-blue bill, finely vermiculated light-brown upperparts, whitish underparts, and a long black pointed tail. The bird’s black rump and wings contrast with its lighter body, giving it a sleek and elegant appearance.

Adult Appearance

• Bill: Stubby, silver-blue in color.
• Upperparts: Finely vermiculated light-brown, with a pattern of fine, wave-like markings.
• Underparts: Whitish, providing a subtle contrast to the brown upperparts.
• Tail: Long and black, pointed at the tip.
• Wings: Black, matching the tail and rump.

Immature Appearance

Immature African Silverbills are similar to adults but lack the fine vermiculations on the upperparts. They also have a slightly duller bill and less defined plumage patterns.

Vocalization

The African Silverbill is known for its “tseep” call and trilling song. The male’s contact call is a single “tseep,” while the female’s call is a double-noted “tsip-tsip.” When in flight, the birds maintain a constant “tseep tseep tseep” sound, which helps to keep the flock together.

Taxonomy

• Scientific Name: Euodice cantans
• Family: Estrildidae
• Genus: Euodice
• Species: E. cantans
• Common Names: African Silverbill

The African Silverbill was first formally described by the German naturalist Johann Friedrich Gmelin in 1789 under the binomial name Loxia cantans. The specific epithet “cantans” is derived from Latin, meaning “singing,” which reflects the bird’s melodious vocalizations.

Historical Taxonomy

Initially, the African Silverbill was considered conspecific with the Indian Silverbill (Euodice malabarica). However, studies in the mid-20th century, particularly by Colin Harrison in 1964, established that the two were distinct species. Harrison noted that while the call notes of the two species were similar, their songs differed significantly. Additionally, these species are sympatric in the southern Arabian Peninsula but do not hybridize naturally, further supporting their classification as separate species.

Subspecies

There are two recognized subspecies of the African Silverbill:

1. Euodice cantans cantans: The nominate subspecies, found in West Africa.
2. Euodice cantans orientalis: Found in East Africa, this subspecies is darker on the face and upperparts compared to the nominate form.

Distribution

The African Silverbill is native to the dry savanna regions south of the Sahara Desert, extending from Senegal in the west to Ethiopia and Somalia in the east. The species has also been introduced to various other regions, including Portugal, Qatar, and parts of the United States, where it has established small feral populations.

Table: Distribution of African Silverbill

Range and Population

The African Silverbill is common throughout its native range in Africa, particularly in dry savannas and grasslands. The species has adapted well to various environments, and its population is considered stable across its native and introduced ranges.

Table: Population Estimates by Region

Habitat

The African Silverbill primarily inhabits dry savannas, grasslands, and semi-desert regions. It is often found near water sources, such as rivers and lakes, where it can find both food and nesting materials. The species is highly adaptable and can also thrive in agricultural areas and human-modified landscapes.

Preferred Habitat

• Primary Habitat: Dry savannas, grasslands, semi-desert regions
• Secondary Habitat: Agricultural fields, suburban areas, parks
• Altitude Range: Sea level to 1,500 meters above sea level

In regions where it has been introduced, the African Silverbill often occupies similar habitats, demonstrating its adaptability to a range of environmental conditions.

Behavior

The African Silverbill is a highly social bird, often seen in flocks that range from a few individuals to several hundred. These flocks are most commonly observed foraging together on the ground, searching for seeds and small insects. The species is also known to roost communally, often with other species of finches.

Social Structure and Foraging Behavior

The African Silverbill feeds primarily on grass seeds, which it forages from the ground or directly from plants. The bird’s stubby, silver-blue bill is well-adapted for cracking seeds, making it an efficient granivore. The species’ social nature is reflected in its flocking behavior, where individuals remain in close contact through constant vocalizations.

• Foraging Behavior: Ground-dwelling, primarily seed-eater
• Social Structure: Highly social, forms large flocks
• Vocalizations: “Tseep” call, trilling song used for communication

Feeding

The diet of the African Silverbill consists mainly of grass seeds, which are abundant in its dry savanna habitat. During the breeding season, the bird’s diet may expand to include small insects, which provide essential protein for raising chicks.

Table: Seasonal Variation in Diet

Breeding

The breeding season of the African Silverbill varies across its range but generally occurs during the wet season when food is most abundant. The species is monogamous, with strong pair bonds that often last for several breeding seasons.

Nesting Behavior

The African Silverbill constructs a dome-shaped nest using grass, twigs, and other plant materials. These nests are typically built in bushes, trees, or man-made structures such as buildings or nest boxes. The female lays 4 to 6 eggs, which both parents incubate for about 11-13 days. After hatching, both parents participate in feeding the chicks, which fledge approximately 17-21 days after hatching.

• Nesting Site: Bushes, trees, man-made structures (e.g., buildings, nest boxes)
• Nest Construction: Dome-shaped, made of grass and twigs
• Clutch Size: 4-6 eggs
• Incubation Period: 11-13 days
• Fledging Period: 17-21 days

Migration

The African Silverbill is primarily a sedentary species, with most populations remaining within their local area throughout the year. However, some local movements may occur in response to changes in food availability or environmental conditions.

• Migration: Primarily sedentary, with some local movements

Threats

The African Silverbill is currently listed as “Least Concern” by the IUCN due to its wide distribution and stable population. However, certain threats could impact local populations, particularly habitat loss due to agricultural expansion and urbanization. The use of pesticides in farming also poses a potential threat to the species, particularly during the breeding season when insect consumption increases.

Table: Threat Analysis

Conservation Status

The African Silverbill is classified as “Least Concern” on the IUCN Red List, reflecting its stable population trends and widespread distribution. Conservation efforts are minimal, given the species’ adaptability and resilience, but ongoing monitoring is recommended to ensure that the species remains abundant in both its native and introduced ranges.

Conclusion

The African Silverbill is a resilient and adaptable species that has successfully established itself across a wide geographic range. Its distinctive appearance, social behavior, and ease of care in captivity have made it a popular bird among aviculturists worldwide. While currently not at risk, the African Silverbill’s widespread introduction to non-native regions and potential threats from habitat loss and pesticide use warrant continued observation. As one of the most widespread and easily recognized members of the finch family, the African Silverbill continues to captivate bird enthusiasts and researchers alike.