White-rumped Falcon

The White-rumped Falcon is a small, little-known raptor of dry deciduous forests in Southeast Asia, most closely related to the African Pygmy Falcon despite the geographic separation between the two species.

Its most useful field and feather mark is the contrasting white rump, visible in flight and present as a distinct patch of white feathers at the base of the tail, a feature not shared with most other small Asian falcons.

Because it favors open, dry forest with scattered large trees, feathers are typically found in such woodland rather than dense evergreen forest.

Shape and size

• Flight feathers are small, in keeping with its diminutive body size, generally under 10-11 cm.
• Rump feathers are distinctly white and contrast sharply with darker surrounding feathers, a key diagnostic patch.

Color and pattern

• Male back and head feathers are grey; female back feathers are chestnut-rufous, mirroring the sexual difference seen in the African Pygmy Falcon.
• Underparts feathers are pale, whitish to buff, with little or no streaking.
• Shafts are pale on white rump feathers, darker on back and flight feathers.

Similar species

• The white rump patch separates it from most other small Southeast Asian falconets, which lack this feature; overall tiny size distinguishes it from larger regional falcons.

Males show a grey head and back with a white rump and pale underparts; females replace grey with chestnut on the back, again similar to the pattern in the African Pygmy Falcon. Juveniles resemble females with some duller fringing that is lost after the first molt.

Restricted to dry deciduous forest and open woodland in parts of Southeast Asia, including Myanmar, Thailand, Laos, and Cambodia. It is a non-migratory resident and considered uncommon to rare in much of its range.

Hunts insects and small vertebrates from perches in open woodland, often near clearings. Nests in tree cavities, sometimes old woodpecker or barbet holes. Calls are thin and high-pitched, typical of small falcons.

Field note: a small feather showing a clean white rump patch found in dry deciduous forest in mainland Southeast Asia is a strong candidate for this uncommon species.