Variable Sunbird

The Variable Sunbird is a tiny, energetic nectar-feeder found across East Africa, from South Sudan and Ethiopia south through Kenya and Tanzania. It gets its common name from the striking degree of plumage variation shown by males across different populations, which for decades led to confusion over how many species were actually involved.

Appearance

Males are iridescent, typically combining a metallic green or blue-green crown, throat and upper back with a violet or blue chest band, and a belly that ranges from bright yellow to sooty black depending on the subspecies. Females are far plainer: olive-grey above and pale yellowish below, lacking any iridescence.

Like other sunbirds, the bill is slender and downcurved, adapted for probing tubular flowers, and the wings are short and rounded.

Key field marks

• Small size (about the size of a warbler) with a thin, curved bill
• Male: iridescent green/blue head and throat, a narrow band of violet-blue across the breast, and a belly color that varies geographically from yellow to blackish
• Female: plain olive-grey above, dull yellow below, no bright colors
• Constant hovering and darting flight around flowering trees and shrubs

Similar species

Because male plumage varies so much between populations, local field guides are essential for pinning down exact appearance in a given region. Females and immatures are easily confused with other small sunbirds such as the Collared or Olive Sunbird; the combination of habitat, range, and lack of any breast band or throat patch usually narrows things down. Male Collared Sunbirds show a clean narrow purple collar on an otherwise unmarked green-and-yellow body, distinguishing them from the more blotchy-bellied Variable Sunbird.

Habitat

Variable Sunbirds favor open and semi-open habitats: acacia savanna, woodland edges, coastal scrub, cultivated gardens, and flowering ornamental trees in towns and cities.

Range

The species occurs widely across East Africa, including South Sudan, Ethiopia, Somalia, Uganda, Kenya, and Tanzania, generally at low to mid elevations.

Migration

Most populations are resident, though some local movements track the flowering and fruiting seasons of favored nectar plants.

Behavior

Active and pugnacious for its size, the Variable Sunbird will chase other sunbirds and even much larger birds away from productive flowering trees. It moves quickly between blossoms, feeding while perched rather than hovering for extended periods like a hummingbird, though brief hovering bouts do occur.

Voice

The song is a fast, high-pitched jumble of chips and twitters, often delivered from an exposed perch. The call is a sharp, metallic "tsip" or "chip" note.

Feeding

Nectar makes up the bulk of the diet, supplemented by small insects and spiders gleaned from foliage or caught in short aerial sallies, which provide essential protein, especially when feeding young.

Nesting

The nest is an untidy, purse-shaped structure of grass, plant down, and spider web, suspended from a thin branch or twig with a side entrance hole, often partly shielded by an overhanging "porch." The female typically incubates one or two eggs alone.