Falcons of Puerto Rico

American Kestrel: the falcon that lives here

The American Kestrel is a common resident across the West Indies and a common breeder in Puerto Rico, including Vieques, Mona, and Culebra. It is seen most in the dry south, but it uses farms, pastures, open country, forest edges, and even towns and cities. In the atlas it appeared in 327 of 479 hexagons (68%), with 537 records.

It nests in cavities it does not excavate: woodpecker holes in trees or crevices in cliffs, so a shortage of cavities can limit it. The atlas found breeding year-round, most active from March to June and peaking in June. It is in no local or federal threat category.

How to recognize the American Kestrel

It is North America's smallest falcon, with two sharp black vertical stripes on the face. Males have blue-gray wings; females are reddish-brown above. It hunts from a post or wire, or hovering over grassland, and drops onto grasshoppers and other large insects, as well as small mammals and birds.

Its call is a shrill, repeated “killy-killy-killy,” easy to recognize once heard, which is why it is this guide's featured sound. If you see a small falcon perched on a wire in Guánica, Cabo Rojo, or a city lot, start with this species before thinking Merlin.

Merlin: the winter hunter

The Merlin is 25 to 36 centimeters long, compact, with a relatively short dark tail crossed by narrow pale bands, a streaked chest, and no strong Peregrine-style mustache. It hunts mainly small birds with fast, direct flight, and also takes dragonflies, rodents, and bats. Its official local name is Falcón Migratorio.

A classic study at a cave in Aguadilla, published in 1985, documented Merlins present from October to April over two winters, peaking in January and February. The falcon at the most visible perch took about 5.1 bats per day, and in the first season Merlins took about 1,800 bats from the more exposed flyway. Lists disagree on how frequent it is, so document every record with a photo.

Peregrine Falcon: the large seasonal visitor

The Peregrine is the largest of the four, 36 to 48 centimeters long, with long pointed wings, a blue-gray back in adults, and a thick black mustache. It hunts almost only birds, often from great height, along coasts, salt flats, wetlands, and cities with pigeons.

It comes from populations that breed in the north and is not documented nesting on the island, so its season runs roughly from autumn to spring. We have a full guide to the Peregrine Falcon in Puerto Rico covering where to look, how it hunts, and its conservation story.

Aplomado Falcon: a record that made history

The first Aplomado Falcon for Puerto Rico and the entire West Indies appeared at Laguna Cartagena National Wildlife Refuge in the southwest on January 15, 2008, and stayed until January 25. Several observers photographed it during long viewing periods, and the record was published in 2011 in The Wilson Journal of Ornithology.

It is an elegant falcon, 36 to 41 centimeters long, with black flank patches that nearly meet on the lower breast, a rufous belly and thighs, and a long tail with narrow white bars. It lives in grasslands and open country on the American mainland; in Puerto Rico it remains accidental, and any new report needs photos.

How to separate them, and why the Sharp-shinned Hawk is not a falcon

Start with size and behavior: if it hovers over grass, it is almost certainly a kestrel; if it is compact and passes low and very fast after small birds in winter, think Merlin; if it is large, heavily mustached, and hunts over coastal flocks, think Peregrine. A long-tailed falcon with a rufous belly and black flanks deserves immediate photos.

Falcons have long, pointed wings. The Sharp-shinned Hawk (falcón or gavilán de sierra) has short, rounded wings, a long square-tipped tail, and a flap-and-glide flight among montane forest trees. It is another family, another hunting style, and a critically endangered subspecies.

How many falcons are there in Puerto Rico?

Four Falco species are recorded: the American Kestrel (resident), the Merlin and the Peregrine Falcon (northern visitors), and the Aplomado Falcon (one accidental record in 2008). The list also includes an extinct endemic caracara known only from subfossil remains.

What is the falcón común?

It is the local name for the American Kestrel (Falco sparverius), Puerto Rico's only resident falcon. It is small, with two black face stripes, hunts large insects from posts or while hovering, and nests in cavities.

Is the falcón de sierra a falcon?

No. The falcón de sierra is the Sharp-shinned Hawk (Accipiter striatus venator), an accipiter hawk. It has short rounded wings and a long tail, lives in montane forest, and is endangered.

Is there an Aplomado Falcon in Puerto Rico?

Only as a rarity. The first Aplomado Falcon for Puerto Rico and the West Indies stayed at Laguna Cartagena from January 15 to 25, 2008, and was photographed by several observers. It is neither resident nor regular on the island.

What is a Merlin?

The Merlin (Falco columbarius) is a small, compact falcon that breeds in the north and visits Puerto Rico in winter. A study in Aguadilla documented Merlins from October to April hunting bats at a cave exit.

What does the American Kestrel sound like?

Its best-known call is a shrill, repeated “killy-killy-killy,” easy to recognize once heard. It also makes whines and chitters in other contexts.