Puerto Rico is home to a remarkable diversity of bird species, many of which are active and vocal at night. The island’s tropical climate and varied habitats, ranging from coastal mangroves to moist forests in the central mountains, support over 350 species of birds. Of these, several dozen species routinely call, sing, or make other noises after dark. This article explores some of the most common and distinctive nighttime vocalists in Puerto Rico’s avian community. Understanding which birds make noise at night can help birders and nature enthusiasts identify species by their calls and better appreciate the island’s rich bioacoustics.
Frogs Are Often Mistaken for Night Birds in Puerto Rico
Before identifying Puerto Rico’s nocturnal bird species, it is important to note that two types of frogs are often mistaken for singing night birds on the island: the common coquí frog and the Cuban tree frog. The loud, repetitive calls of male coquí frogs reverberate through Puerto Rico’s forests and gardens on warm, humid nights. These widespread frogs produce a distinctive “ko-kee” vocalization, sometimes described as sounding like a bird chirping. Meanwhile, invasive Cuban tree frogs emit drawn-out trills reminiscent of certain birds. Distinguishing frog calls from actual bird vocalizations takes some practice for the uninitiated. Once the difference is clear, a fascinating array of avian sounds emerges after dark in Puerto Rico.
Owls
Several species of owls common in Puerto Rico vocalize at night, including:
Puerto Rican Screech-Owl
The Puerto Rican screech-owl (Megascops nudipes) is endemic to the island. It produces a haunting, whistling call described as a soft, tremulous whinny or sustained trill. This medium-sized owl nests in tree cavities and is most vocal on moonlit nights or near dawn.
Puerto Rican Lizard-Cuckoo
Formerly known as the Puerto Rican screech-owl, the Puerto Rican lizard-cuckoo (Coccyzus vieilloti) is also endemic to the island. Its territorial call is a low-pitched “oo-oo-oo” that rises slightly at the end. Less vocal than other Puerto Rican owls, its primary call period is just before dawn.
Puerto Rican Short-eared Owl
The Puerto Rican short-eared owl (Asio flammeus portoricensis), a Puerto Rican subspecies, inhabits open grasslands. Its call is a gruff, throaty bark, given most often during courtship or as an alarm. This owl is now rare on Puerto Rico.
Northern Saw-whet Owl
A winter visitor, the northern saw-whet owl (Aegolius acadicus) can be identified by an eerie, continuous trilling call. Its calls tend to be higher-pitched than the Puerto Rican screech-owl.
Nightjars
Four members of the nightjar family (Caprimulgidae) occur in Puerto Rico, of which two regularly vocalize at night:
Puerto Rican Nightjar
The Puerto Rican nightjar (Antrostomus noctitherus) is endemic to the island. Males give a loud, carrying “whip-poor-will” call, most actively on moonlit nights. They may call for hours from a favored exposed perch.
Common Nighthawk
A winter visitor, the common nighthawk (Chordeiles minor) is famous for its buzzy “peent” territorial call as it flies over open areas at night. Nighthawks sometimes call continuously through the night during migration.
Hummingbirds
Surprisingly, some hummingbirds vocalize at night as well:
Puerto Rican Emerald
The Puerto Rican emerald (Chlorostilbon maugeaus), found only on the island, gives a thin “seep” call at night during the breeding season, along with wing-clapping sounds. Calls seem to function to defend territory.
Antillean Mango
A common resident, the Antillean mango (Anthracothorax dominicus) sings a squeaky, twittering song from its roost or perch at dawn and dusk. This helps establish territory and communicate with mates.
Swallows and Swifts
The aerial masters produce social and territorial calls as they roost overnight:
Caribbean Martin
The Caribbean martin (Progne dominicensis) roosts communally in reed beds. Their overnight roosts pulse with twittering calls and chatter.
Antillean Palm Swift
Nesting in palm cavities and crowns, the Antillean palm swift (Tachornis phoenicobia) is known for constant, high-pitched screeching at dawn and dusk from large flocks.
Nightjars
Four members of the nightjar family (Caprimulgidae) occur in Puerto Rico, of which two regularly vocalize at night:
Puerto Rican Nightjar
The Puerto Rican nightjar (Antrostomus noctitherus) is endemic to the island. Males give a loud, carrying “whip-poor-will” call, most actively on moonlit nights. They may call for hours from a favored exposed perch.
Common Nighthawk
A winter visitor, the common nighthawk (Chordeiles minor) is famous for its buzzy “peent” territorial call as it flies over open areas at night. Nighthawks sometimes call continuously through the night during migration.
Rails
These secretive wetland birds make distinctive calls at night:
Clapper Rail
The clapper rail (Rallus crepitans) announces its presence with a loud, raucous “kek-kek-kek” from marshy areas. Most vocal at dawn and dusk.
Spotted Rail
Reclusive but noisy, the spotted rail (Pardirallus maculatus) produces pig-like squeals and grunts, often in concert with others. Their cacophony carries across wetlands.
Sora
Winter visitor to marshes and wet pastures. Identifiable by a descending whinny call “wheeeeee-who.” Most vocal at dusk and dawn.
Thrushes
Some of Puerto Rico’s thrush species sing beautifully at dawn, dusk, and intermittently through the night:
Ruddy Quail-Dove
The ruddy quail-dove (Geotrygon montana) inhabits forest and woodland understories. Its rhythmic three-note call “doo-doo-doo” rings through the darkness.
Pearly-eyed Thrasher
Common in thickets and woodlands. Its rich warbling song and sharp chattering calls carry well at night. Most vocal before dawn.
La Sagra’s Flycatcher
This forest thrush is easier heard than seen. Its fluty, whistled song “oh deeee oh” echoes at dusk and after dark.
Other Birds
Additional Puerto Rican birds that vocalize at night include:
Lesser Antillean Bullfinch
A common finch with a soft, melodic warbling and chattering song, often from dawn through mid-morning.
Gray Kingbird
Aggressive tyrant flycatcher with a piercing “pip-PIT-squeeee” call used to defend territory after dark.
Bananaquit
Tiny but loud songster with an accelerating series of chirping notes “brrr-diddy-ditt” in first light.
Yellow-faced Grassquit
Small seedeater with cheerful buzzy trilling from grassy areas around dawn and dusk.
When are birds most vocal at night in Puerto Rico?
Peak calling times for Puerto Rico’s vocal nocturnal birds include:
– Just after dusk and before dawn (dusk and dawn choruses)
– Through the first few hours of nightfall
– In the hour before dawn
– On moonlit nights (light aids nocturnal activity)
Not all species vocalize throughout the night. Hummingbirds, swifts, swallows, and thrushes, for example, are most actively calling in dusk and dawn twilight periods. Owls and nightjars are more likely to call sporadically through the night. Environmental factors like moon phase, time of year, and weather patterns also impact vocal activity.
Where to listen for nocturnal birds in Puerto Rico
Prime birding areas to listen for nighttime vocalizations include:
– Coastal wetlands – Clapper rails, spotted rails
– Forest edges – Owls, La Sagra’s flycatcher, bananaquits
– Open fields – Common nighthawks
– Forest interior – Screech-owls, nightjars, ruddy quail-doves
– Near water – Rails, spotted sandpipers
– Urban areas – Northern mockingbirds, gray kingbirds
Conclusion
Puerto Rico’s nocturnal birds create a rich chorus of calls, songs, and sounds after dark. Common vocalists include owls, nightjars, thrushes, rails, hummingbirds, and others. Coastal and inland wetlands, forests, and forest edges provide the best opportunities to appreciate their mesmerizing nocturnal vocalizations. With keen listening skills and some practice distinguishing bird sounds from frogs, one can discover the diverse array of avian species that vocalize across Puerto Rico once the sun goes down.