See the First-Ever Photographs of Cozumel’s Elusive Dwarf Fox, One of the Rarest Canids in the World
No one had seen the creatures in more than two decades, leading scientists to wonder whether they’d gone extinct. That changed in September 2023
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Early in the morning on Sept. 14, 2023, social media began lighting up with reports of a small, disoriented fox on the eastern side of the island of Cozumel, Mexico.
Rafael Chacón, a wildlife photographer and the director of conservation and environmental education for La Fundación de Parques y Museos de Cozumel (FPMC), grabbed his camera and headed toward the creature’s last-known location on Cozumel’s coastal highway.
When he arrived, he felt a mixture of surprise and disbelief when he realized what he was looking at: a rare and elusive Cozumel dwarf fox. Roughly the size of a small house cat, the creature had a long tail, large erect ears and soft fur that ranged in color from gray to gold to white.
“Seeing this fox standing there, calm and beautiful in its natural habitat, felt almost unreal,” he tells Smithsonian magazine. “The moment … was truly unforgettable.”
Chacón raised his camera and snapped a blurry photo of the adult male as it hid behind some foliage. It was the first time anyone had ever photographed one of the enigmatic foxes, and the first confirmed sighting in more than two decades, Chacón and other scientists report in a study published in May in the journal Neotropical Biology and Conservation.
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Gray foxes (Urocyon cinereoargenteus) have lived on Cozumel for thousands of years. But over time, scientists think they’ve evolved to become smaller versions of their mainland cousins. The same thing happened to the pygmy raccoon and the dwarf coati, which are recognized as distinct species or subspecies unique to Cozumel and found nowhere else on Earth.
Cozumel’s dwarf fox population, however, has never been formally described or recognized as a distinct species. Sightings are exceptionally rare—the last confirmed observation, until now, was in 2001—and the only physical evidence of the creatures comes from 500 to 1,500-year-old remains excavated from Maya archaeological sites.
“Virtually nothing is known about this population, and no species-specific, systematic survey has ever been conducted,” the researchers write in the paper. “However, it is considered critically endangered by scientific consensus and likely on the brink of extinction.”
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After Chacón snapped the image, he and others at FPMC rescued the fox and took it in for a health check. The animal was released three days later into the Laguna Colombia State Reserve in southern Cozumel, after which it stuck around for a little photoshoot.
The encounter proves that the unique creatures have not yet disappeared altogether—but scientists remain concerned about their long-term prospects. They face numerous threats, including vehicle collisions and predation by non-native predators like feral dogs and cats.
Now that a dwarf fox has been spotted, the study’s co-authors are calling for more targeted research and conservation efforts, including morphological and genetic studies to clarify whether they are indeed a separate species.
“Improved documentation and formal description of this insular fox will be critical for informing effective management, protective policies and long-term conservation strategies,” they write in the paper.
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Benjamin Sacks, an ecologist at the University of California, Davis who was not involved with the research, agrees that genetic testing is crucial for understanding and protecting the island’s foxes.
“This is one of the few large terrestrial mammals and the only carnivore I am aware of that has never been adequately described and for which no genetic data has ever been produced,” he tells Smithsonian.
The prospect of obtaining DNA that would allow researchers to sequence the animal’s entire genetic instruction book, or genome, is “especially exciting,” he adds, because it would “tell us exactly how divergent it was from the mainland gray fox.” Additionally, comparing the Cozumel dwarf fox’s genomic data with that of the island fox (Urocyon littoralis)—a distinct species endemic to the Channel Islands off southern California—might also help scientists better understand the “selective machinery” of island dwarfism, he adds.
Island, or insular, dwarfism is an evolutionary phenomenon in which organisms that become isolated gradually shrink in size compared to their mainland relatives. Scientists think this happens because islands often have limited food resources, which creates pressure for animals to survive on fewer calories, as well as fewer predators and less space. Over many generations, scientists theorize, natural selection favors smaller individuals that require less energy, eventually leading to a dwarf population or an entirely separate species. Examples include tiny elephants that once lived on Sicily, miniature hippos that evolved off the coast of Africa and early humans known as Homo floresiensis that once inhabited the island of Flores in what’s now Indonesia.
Did you know? Some animals grow larger on islands
Island life leads some creatures to become bigger than their mainland counterparts, a phenomenon called island, or insular, gigantism. An increase in food or a decrease in predators might lead to the size change. Often, smaller animals like rodents become larger, while bigger animals and carnivores shrink.
Formally publishing Chacón’s photographs in a scientific journal was the first step toward protecting Cozumel’s dwarf foxes, according to lead author Travis Bayer, a biologist and the founder and executive director of the conservation organization Pathos Wildlife.
But now that they know the foxes are still out there, scientists and conservationists need to get to work, Bayer tells Smithsonian. He’s collaborating with other researchers to conduct a large, species-specific camera trap survey to understand where the foxes live and how many individuals might still be roaming around the island. They’ve installed 84 remote cameras around the island and are using a gray fox scent lure to attract the island’s foxes. The camera stations are also equipped with adhesive hair snares, which they hope will allow them to opportunistically collect DNA samples from any individuals that investigate the scent.
“While [the] photographic evidence confirms the existence and survival of the Cozumel fox, it remains unstudied in the wild, undescribed by science, unassessed by the [International Union for Conservation of Nature] and unprotected while at immediate risk of extinction,” Bayer says. “Without efforts to document and describe the species, they risk disappearing before they’re even known.”
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