Fork-tailed Palm Swift

This is a small, highly specialized member of the Apodidae family characterized by its slender silhouette and remarkable adaptation to an aerial lifestyle. It measures approximately 11 to 12 centimeters in length and weighs between 9 and 11 grams. The plumage of the upperparts is predominantly dark olive-brown, whereas the underparts are a lighter, pale grayish-brown, with the throat area presenting a distinctly paler coloration with fine, subtle streaking. Its most diagnostic morphological feature is its deeply forked tail, which is frequently held tightly closed during flight, giving the illusion of a single, long needle-like projection. The wings are exceptionally long, narrow, and curved in a scythe-like shape, facilitating highly agile and acrobatic flight patterns.

Geographical distribution: This species is widely distributed across the lowlands of South America, strictly to the east of the Andes mountain range. Its geographical range encompasses countries such as Colombia, Venezuela, the Guianas, Ecuador, Peru, Bolivia, and vast territories of Brazil, particularly throughout the Amazon basin and the Cerrado biome. Two subspecies are generally recognized: Tachornis squamata squamata, occurring in the eastern portion of its distribution, and Tachornis squamata semota, which occupies the western and southern regions of the Amazon.

Habitat: It exhibits an obligate and strict ecological dependence on landscapes containing mature palm trees, most notably the moriche or buriti palm (Mauritia flexuosa). It primarily frequents flooded savannas, tropical humid forest edges, palm swamps, wooded grasslands, and increasingly, urban and suburban environments, including city parks where native or exotic dense-canopy palms have been introduced.

Feeding: It is an obligate aerial insectivore, capturing its prey entirely on the wing. Its diet consists of a diverse array of small flying insects that constitute aerial plankton. Preferred prey items include winged termites, flying ants, small beetles, flies, true bugs, and tiny wasps. Its foraging behavior involves rapid sweeps over the forest canopy, open savanna, and slow-moving bodies of water where insect densities are highest, particularly during the early morning and twilight hours.

Behavior: This highly gregarious bird is almost always seen in flocks ranging from a dozen to several hundred individuals. It spends the vast majority of its daylight hours in continuous flight, characterized by rapid, jerky wingbeats interspersed with brief, gliding phases. Flock members maintain cohesion through high-pitched, buzzy, and metallic calls. At dusk, the flock converges on palm trees, performing synchronized entries into the hanging, dead fronds where they roost vertically, clinging to the dry plant fibers with their powerful claws.

Nesting: The reproductive biology of this swift is intimately tied to the structural architecture of palm fronds. It constructs a unique, vertically oriented, sleeve-like nest attached to the inner surface of dead, hanging leaves of palms, particularly Mauritia flexuosa. The nest is meticulously fashioned from feathers, plant down, and seed pappi, all bound together and cemented to the leaf using the bird´s own sticky saliva. Within this vertical pocket, the female deposits 2 to 3 pristine white eggs. Because of the nest´s vertical orientation, both the eggs and the subsequent chicks are glued or firmly wedged into the nest material by the saliva, preventing them from falling out during high winds.

Conservation status: It is currently classified as Least Concern (LC) on the IUCN Red List of Threatened Species. The global population is considered stable, and in some anthropogenically modified landscapes, it is actually expanding its range. This local expansion is driven by the widespread planting of ornamental palms in urban areas and the creation of open pastures, which provide abundant foraging territory.