The Antillean palm swift, Tachornis phoenicobia, is a diminutive bird, measuring a mere 9 to 11 centimeters in length and tipping the scales at approximately 9 to 11 grams. It is characterized by its long, slender wings and a medium-length, forked tail. Both sexes present a similar appearance.
Adults of the nominate subspecies boast a dark sooty brown crown and nape, with their back, a narrow center strip of the rump, uppertail coverts, and tail ranging from sooty black to black. The rump's sides are a contrasting white. Their wings are a sooty blackish hue with pale edges on the flight feathers. The face is predominantly grayish brown, while the underparts are mostly a dull white, with dark sooty brown flanks, a narrow band across the breast, and undertail coverts. Immature birds are akin to adults but have even duller white underparts and paler sooty brown flanks and undertail coverts.
This swift frequents dry grassy areas dotted with palms, scrublands, forests, and even suburban and urban environments. It can be found at elevations up to 1,700 meters on Hispaniola and 1,200 meters on Jamaica.
The nominate subspecies is native to Jamaica, Hispaniola, and some neighboring small islands. The T. p. iradii subspecies resides on mainland Cuba and Isla de la Juventud. Vagrant sightings have been recorded in Florida, and there are unconfirmed reports from Puerto Rico, the Cayman Islands, Inagua in The Bahamas, and the Turks and Caicos Islands.
The Antillean palm swift is a permanent resident within its range, although some individuals have been known to stray.
The flight call of the Antillean palm swift is a noisy, almost constant, weak twittering, described as "tooee-tooee."
Breeding season for this swift in Cuba spans from May to July, and from March to May on Hispaniola. They construct a hanging pouch nest from plant fibers and feathers, bound together with saliva and suspended from the underside of a dead drooping palm frond. They breed in small colonies, with clutch sizes ranging from two to five eggs. Both parents share the duties of incubating the eggs and caring for the young.
The Antillean palm swift is an aerial insectivore, foraging close to the ground over vegetation, typically in small flocks. It may occasionally forage alongside swallows.
The IUCN has classified the Antillean palm swift as Least Concern. It has a broad range and, while the exact population size is unknown, it is believed to be stable. There are no immediate threats identified, and the species has shown adaptability to human environments, with the planting of ornamental palms providing additional nesting opportunities.