La Jornada: After more than 20 years without registration, the Cozumel dwarf fox reappears

After 20 years without confirmed records, the Cozumel dwarf fox, one of the rarest canids on the planet, was sighted again on the Caribbean island, where it has evolved in isolation for millennia, according to a study published in the journal Neotropical Biology and Conservation.

The discovery was made by biologist Rafael Chacón Díaz, during the early hours of September 14, 2023, when he returned from a tour of the Punta Sur Ecotourism Park, an area that combines white sand beaches, mangrove jungle, lagoons and extensive coral reefs.

“I was returning from the Punta Sur turtle camp, and I saw him in the middle of the street,” he said. The specimen was near kilometer 29 of the coastal highway, and although it was disoriented, it was healthy and without injuries.

After undergoing a complete health evaluation, he was released on September 17, 2023 in the Laguna Colombia State Reserve, one of the largest protected areas on the island, considered a sanctuary for flamingos, crocodiles and migratory birds, far from roads.

A photographic record remained from that encounter that caught the attention of researchers Travis D. Bayer and Maggie A. McGreal, who arranged funds and permits to start a monitoring program for the species that, despite its long evolutionary isolation, has not been described or recognized as a distinct species.

“We had had a couple of sightings in 2002, and in 2003 a team of researchers did work with mammals on the island, but we were not lucky enough to see it. In 2010, when I ran into it on the road, I couldn’t take photographs,” Chacón said.

Although the dwarf fox has inhabited Cozumel for thousands of years, evidence of its existence was scarce and came from subfossil remains found on the island. Researchers even estimate that its presence could predate the settlement of the first Mayans.

According to the article, island isolation could have driven rapid evolutionary divergence and a process of dwarfism. Scientists estimate that the Cozumel dwarf fox is 60 to 80 percent the body size of its closest continental relative: the gray fox. Although morphological or genetic evaluations have never been performed, reports suggest that their isolation began between 5,000 and 37,000 years ago.

Chacón Díaz mentioned that due to the change in land use in the southern part of the island, along with the presence of invasive species and natural disasters, the dwarf fox is in critical danger of extinction.

“Deforestation, urbanization and roads represent a risk for the species,” he noted.

Chacón, a member of the Cozumel Parks and Museums Conservation area, highlighted the importance of this sighting as an urgent call to study it, identify the size of its population and, above all, undertake conservation actions.

The scientific article, published by Bayer, McGreal and Chacón, states that priority actions should include studies aimed at the species to determine its current distribution and population size, as well as morphological and genetic evaluations to clarify its taxonomic status.

The authors consider it a priority to protect the remaining habitat, reduce conflicts with humans and clarify its status as a species. Otherwise, a unique population that evolved over thousands of years on Cozumel could disappear before even being officially recognized by science.