Cozumel fox photographed for the first time: not extinct after all

On the Mexican island of Cozumel, a living Cozumel fox has been documented in photographs for the first time. The record is extraordinary because this dwarf island form from the gray fox genus was previously known with certainty only from subfossil bone finds. Although there had been individual sighting reports in the past, they remained unverified: there were no photos, genetic evidence, or morphological examinations of living animals. Researchers therefore considered the Cozumel fox lost—possibly even long extinct.

The photos now published in the journal Neotropical Biology and Conservation fundamentally change that assessment. They show an adult male that was discovered on the east side of Cozumel on September 14, 2023, briefly captured, examined, and released a few days later in a protected area. It is the first photographic evidence of this virtually unknown fox population and the first confirmed sighting in more than two decades.

A little-studied island form in the gray fox lineage

The Cozumel fox belongs to the genus Urocyon, which today includes two living species: the widespread gray fox (U. cinereoargenteus) on the American mainland and the island fox (U. littoralis), which occurs only on six of California’s Channel Islands. The island gray fox is a well-studied example of how strongly island isolation can influence evolution: after its separation from the mainland, it diverged markedly from its continental relatives in morphology, genetics, and ecology.

A dwarf fox form has also evidently existed on Cozumel for thousands of years. Archaeological and subfossil finds suggest that this population may have been present on the island even before early Maya settlement. Analyses of the bone remains also point to pronounced island dwarfism: compared with mainland gray foxes, the Cozumel fox could be about 60 to 80% smaller. Exactly when the population became isolated is unclear; previous estimates range from about 5,000 to 37,000 years ago.

Island dwarfism is a well-known evolutionary phenomenon. When animal populations are separated from the mainland for long periods, body size, behavior, and ecology often change substantially. On islands, large predators or competitors may be absent, resources are limited, and small populations can quickly become genetically distinct from their ancestral forms. Under such conditions, some species become larger, others smaller. With the Cozumel fox, a particularly small form appears to have evolved within the gray fox lineage.

Such developments are known from many islands. Madagascar was once home to several endemic hippopotamus species, including Lemerle’s hippopotamus; on Sicily, the Sicilian wolf also developed as a distinct island form. The Cozumel dwarf fox belongs in this broader context: it, too, shows how island isolation can produce distinct animal forms and how vulnerable such small, spatially limited populations are.

Cozumel is also known for island-specific traits in other mammals. The Cozumel raccoon (Procyon pygmaeus) and Cozumel coati (Nasua nelsoni) are also much smaller than their mainland relatives and are considered endemic forms of the island. The Cozumel fox, however, occupies a special position within this island community: although subfossil finds indicate a markedly smaller and long-isolated island form, it has not yet been formally described by science.

Its taxonomic status therefore remains unresolved to this day. Whether it is a distinct species, a subspecies, or an isolated population of the gray fox can only be clarified through comprehensive morphological and genetic studies.

Almost nothing is known about its current distribution, population size, ecology, or threat status either. Historical information is extremely rare and consists primarily of individual sightings, eyewitness reports, or secondhand reports. The last sighting mentioned in the scientific literature dates from 2001. Until the current study, however, the only reliable physical evidence came from subfossil bones. Only the photos taken in 2023 proved beyond doubt that this little-known island form is in fact still alive.

That is why the new record is so significant. The Cozumel fox was not only rarely seen, but almost invisible scientifically: not formally described, not genetically studied, not systematically monitored. On its website, the organization Pathos Wildlife describes it as one of the rarest canids in the world.

Found on the coastal road

In the early morning of September 14, 2023, the Fundación de Parques y Museos de Cozumel (FPMC) received several reports of a disoriented fox—via social media as well as by telephone. The FPMC then initiated the animal’s recovery together with Rafael Chacón, one of the study’s eventual authors.

At around 6 a.m., the fox was found on the coastal road on the east side of Cozumel. It was an adult male. Before it was captured, the animal was photographed—the first known photographic record of the mysterious species. The animal was then safely recovered and kept under observation for several days.

After a physical examination, it was released on September 17, 2023, in the Laguna Colombia State Reserve. The release site was selected in coordination with the Mexican environmental authority PROFEPA and the National Commission for Natural Protected Areas CONANP. It was farther away from the road, thereby presenting a lower immediate risk, and, in the assessment of those involved, was more consistent with the fox’s presumed natural habitat.

Habitat in southern Cozumel

The Laguna Colombia State Reserve lies in the south of the island and comprises a mosaic of different habitats: tropical lowland forest, seasonal wetlands, mangroves, coastal dune vegetation, lagoons, open water bodies, and areas with dense understory vegetation. For a small, secretive carnivore such as the dwarf fox, such structures could be crucial: they provide cover, refuges, and presumably suitable feeding habitats.

The records and reports to date suggest that the Cozumel fox may now occur only in the southern part of the island. The study states that the fox population has so far not been reported farther north than the village of El Cedral. If this reflects the actual distribution area, the current range would be extremely small—making protection of the remaining habitats in southern Cozumel correspondingly important.

Yet precisely these habitats are under increasing pressure. The study cites, among other factors, development, land-use changes, invasive species, and natural disasters such as hurricanes as pressures on the south of the island. Further possible risks include habitat fragmentation, road traffic, and Cozumel’s advancing tourism and urban development.

For a very small remnant population, even individual losses could be serious. Roads can not only cause direct deaths but also divide habitats. Development and tourism infrastructure reduce or fragment suitable refuges. Invasive and introduced species could additionally bring competition, predation, or disease risks. Added to this is the fact that hurricanes on an island with a limited distribution area can alter entire habitats within a short time.

The find site and later release in the Laguna Colombia State Reserve therefore show where future conservation measures would need to begin: in southern Cozumel, where historical information, current observations, and suitable habitats coincide.

Why the new evidence is only the beginning

The first photographic evidence fundamentally changes the scientific starting point. An island form that had previously been securely documented only by subfossil bone finds is once again a living, documented animal. The 2023 photograph confirms for the first time beyond doubt that at least one Cozumel fox has survived to the present day.

The find, however, is no all-clear. A fox population that goes without confirmed detection for decades is either extremely rare, very secretive—or both. For the Cozumel fox, almost all data that would be crucial for its protection are still missing: How many animals remain? Where exactly do they occur? Which habitats do they use? Is reproduction still taking place? How large are their home ranges? And which threats—such as road traffic, invasive species, hurricanes, habitat loss, or development—pose the greatest risk?

The unresolved taxonomy is also important for species conservation. If the Cozumel fox represents a distinct, as-yet undescribed species, the issue would not only be the preservation of a small island population, but a possibly unique evolutionary lineage. Genetic and morphological studies would therefore need to clarify how clearly the animals differ from mainland gray foxes, how long their evolutionary history proceeded independently, and how much genetic diversity remains in the remnant population.

The study’s authors therefore emphasize the urgent need for research and action. What is needed are targeted searches, systematic population surveys, and long-term monitoring. Studies in southern Cozumel are particularly important, especially in the Laguna Colombia State Reserve and around El Cedral. There, historical information, current observations, and suitable habitats overlap.

Pathos Wildlife describes the ongoing project as the first targeted attempt to systematically find, scientifically study, and protect the Cozumel fox over the long term. To do this, several non-invasive methods are to be combined: nighttime search flights with thermal-imaging drones, a network of camera traps, and genetic analyses based on hair samples.

Such methods are especially important for an extremely rare, elusive island form that is probably mainly crepuscular or nocturnal. Traditional visual observations quickly reach their limits here. Thermal-imaging drones could help locate animals in densely vegetated areas without entering large areas or directly disturbing the animals. Camera traps can then document over weeks and months when and where foxes appear, which habitats they use, and whether multiple individuals are present.

The planned use of hair traps at camera stations would be particularly informative. Unobtrusive adhesive strips can collect hairs when an animal passes the station. At the same time, reference markers help assess the body size of photographed animals more precisely. Genetic analyses of such hair samples could answer central questions: Are several individuals involved? How closely are they related? How large is the genetic diversity of the remnant population? And how clearly does the Cozumel fox differ genetically from mainland gray foxes?

In the long term, these data could show which areas are especially important for the Cozumel fox, where movement corridors need to be maintained, and which threats should be reduced most urgently. The new photographic evidence is therefore not the end of a search, but its beginning. It shows that this little-known island form still exists—and at the same time how little time may remain to study it and protect it effectively.

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Source

• Bayer, T. D., McGreal, M. A., & Chacón, D. A. R. (2026). First photographic evidence of an insular dwarf fox (Urocyon sp.) on the island of Cozumel, Mexico. Neotropical Biology and Conservation, 21(2), 123–129. https://doi.org/10.3897/neotropical.21.e187967