Caribbean islands were once the center of diversity for barn owls

Key points

• Barn owls dispersed to North America from Eurasia between the Pliocene and early Pleistocene epochs, less than 5 million years ago, likely by crossing the Atlantic Ocean.
• A new study conducted by scientists at the Florida Museum of Natural History shows that barn owls initially arrived and diversified in the Caribbean, where paleontologists have found fossils of several giant species in this group that are now extinct.
• From the Caribbean, barn owls dispersed to the Galápagos Islands. Afterward, Caribbean barn owls made their way onto the North and South American continents.

GAINESVILLE, Fla. --- Legend has it that a giant elfin, owl-like creature called the chickcharney haunts the islands of the Bahamas. Those who encounter this cryptid on cordial terms are said to be blessed with good luck. Those who disrespect the chickcharney, however, don’t fare as well.

“If you see one shoe in the field, it means that chickcharney came, picked up this person and took them away,” said Jessica Oswald, recounting a story she was told in the Bahamas.

Oswald visited the islands while she was a postdoctoral associate at the Florida Museum of Natural History in 2017 and 2019. There, she and her colleagues found fossils of what they believe to be the original inspiration for the chickcharney legend.

“Tyto pollens lived in Cuba and the Bahamas, and it was huge, about a meter tall. Humans encountered this species or other giant Tyto species at some point,” she said. “In the Lesser Antilles, there’s evidence of a giant owl species at an archaeological site, showcasing the overlap of humans and these island giants.”

Tyto pollens and a closely related owl of similarly considerable size, the Hispaniolan giant barn owl (Tyto ostologa), both probably went extinct within the last 1 million years, either in the Holocene or late Pleistocene Epoch. Because many of the prey species these giants depended on did not disappear until humans arrived in the region in the mid- to late Holocene, it is plausible that the owls themselves persisted until that time as well.

Barn owls live on every continent except Antarctica, but a new study co-authored by Oswald shows that the region where barn owls were immortalized as a cryptid was also once their center of diversity.

“Looking at their modern distributions, barn owls are widespread across continental America but not so much in the Caribbean. So, you would assume that the Caribbean barn owls came from the continent, right? But actually, based on genetics, we found that the most divergent lineages are in the Caribbean,” said the study’s lead author, Min Zhao, who conducted the research while working as a postdoctoral associate at the Florida Museum.

Barn owls are a familiar fixture of biodiversity in North, Central and South America, but for many years, paleontologists suspected that they only arrived there recently, within the past 2 million years.

“There aren’t pre-Pleistocene fossils of any barn owls anywhere in the Western Hemisphere, and while absence of evidence is not evidence of absence, I suspect they weren’t here or in the West Indies until the Pleistocene or the Pliocene at the earliest,” said David Steadman, study co-author and curator emeritus of ornithology at the Florida Museum.

Before this study, scientists thought barn owls dispersed to the Americas from Europe or Asia, possibly across the Bering Land Bridge (now a strait) that once connected Alaska and Russia or by island hopping across the remnants of the North Atlantic land bridge that long ago may have connected Canada with northern Europe. After fanning out through the mainland, it was assumed that they would have colonized outlying islands, like those in the Caribbean.

The results of this study, however, indicate that not only did barn owls disperse to the Caribbean first, but they also then skipped over the continents entirely on their way to the Galápagos, where they evolved into a lineage that now appears to be endemic to Isabela and Santa Cruz islands after having been extirpated from Floreana Island. It was only after this long-distance dispersal event that they moved on to the mainland.

The authors obtained their results by sequencing DNA from dozens of owl specimens that were collected as long ago as 1876 and curated in 11 museums, including the Florida Museum of Natural History, the American Museum, the Field Museum and Louisiana State University, among other institutions. They combined this with radiocarbon dates from fossils published in other studies to determine approximately when barn owls moved from one place to another. Their results confirmed that the American barn owl, Tyto furcata, originated in the Caribbean less than 2 million years ago.

The results also discount the hypothesis that barn owls dispersed to the Americas over an ancient land bridge, but this wasn’t surprising to Steadman. Growing up on a farm in Pennsylvania, he’d occasionally climb the family’s 35-foot silo to observe the barn owls that roosted on a platform at the top and to dissect the pellets they left behind. The owls returned to the silo year after year, but he noticed they always left before the winter snows — which obscured the meadow voles they hunted — and only returned once the snow had melted.

“Barn owls are tropical and temperate. They can’t handle high latitudes where there’s snow. So, coming over to the Americas via Beringia or the North Atlantic via some blend of Iceland, Greenland and Canada never seemed realistic.”

That means that barn owls likely reached the Caribbean by flying over the Atlantic from Eurasia either during or just before the Pleistocene ice ages. This might seem as implausible as the inferred Caribbean/Galápagos dispersal event, but it’s not without precedent. Plants in the genus Limonium, called sea lavenders, originated in the Mediterranean region and dispersed from there to island archipelagos in Macaronesia and then on to the Caribbean. And owls, though not typically associated with long-distance travel, have a knack for showing up in places where they’re least expected.

In the preface to his book, “The Natural History of North Carolina, Florida, and the Bahama Islands,” naturalist Mark Catesby wrote that during his voyage from England to North America in 1722, “What seemed most remarkable…was that in the latitude of 26 degrees North, about midway between the two continents of Africa and America, which I think cannot be less than 600 leagues, an owl appeared hovering over our ship. This owl after some attempts to rest, disappeared…. That an owl should be able to hold out so long a flight is to me most surprising.”

Steadman, who is now retired after a long and fruitful career of studying birds, was not surprised to learn that barn owls made a trans-oceanic voyage to the Caribbean.

“Owls are good dispersers, and barn owls are probably the best,” he said.

According to Oswald, the Caribbean still supports the highest diversity of barn owls in the Western Hemisphere, but “it’s a very small percentage of what used to be there.” At least nine barn owl species that once lived in the Caribbean, including the presumed progenitor of the chickcharney, are no longer around.

It’s unlikely these elusive animals were hunted for food. Rather, they disappeared when their source of food ran out. Their diet included large rodents, called hutias, that were once diverse and abundant in the region, along with other, even larger prey.

“The two or three biggest forms of the giant barn owls could easily have taken a young ground sloth. They certainly could have taken any of the monkeys, rodents, insectivores and other animals that were too big a prey item for a regular barn owl,” Steadman said.

The sloth once endemic to the Caribbean was the last of the giant ground sloths to go extinct following the arrival of humans to the American continents, though it was much smaller than its massive continental relatives. Most of the hutia species that once roamed the islands were a favorite food item for owls (and in one unusual instance, a fossil skull of an extinct hutia was a home for bees).

But it’s not all doom and gloom for the barn owl, as evidenced by the fact that it’s still around and geographically widespread. In some cases, modern barn owls are even filling in the spaces left by their extinct counterparts.

This is currently happening in Hispaniola, where modern American barn owls were first spotted in the mid-1900s. The giant Hispaniolan barn owl that used to live there likely feasted on large prey, like the 10 hutia species native to the island that people drove extinct. But the American barn owl seems to be content with smaller fare, possibly including but not limited to the invasive rats that now populate the island after having hitched a ride across the ocean from humans.

The same thing is happening in the Galápagos, which supports both the lineage that arrived from the Caribbean more than 1 million years ago and a more recent arrival that likely flew over from South America and has become established on the island of San Cristóbal. That island is heavily populated by people and has several non-native mammals that the owl may be hunting.

The study’s results have hopeful conservation implications as well. Until very recently, barn owls were thought to belong to a single, cosmopolitan species. But genetic studies like this one have shown there are several species in this group. It was only in 2024, for example, that scientists designated the American barn owl as its own species.

This is good news for owls, Steadman said, because people — scientists included — tend to pay more attention to and study things that they think are unique. The barn owl that evolved in the Galápagos after flying over from the Caribbean is currently considered a subspecies of the American barn owl. But the results of this study, the authors say, are enough to warrant its elevation to the rank of species. Steadman said the same may also be true of a little-known subspecies of Caribbean barn owl that lives in the Lesser Antilles.

“There are very few records of it because it’s not considered endemic, and there’s minimal scientific interest in it. Now that we know these things are genetically distinct, there are some great projects out there waiting for people who want to study them.”

The authors published their study in the journal Proceedings of the Royal Society B.

Additional co-authors of the study are Michelle LeFebvre, Robert Guralnick and Joshua Doby of the Florida Museum of Natural History; and Julie Allen of Virginia Tech.

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