Ocelots Are the New Invasive Species in Cozumel
Ocelots are experiencing population declines throughout much of their natural range, which stretches from Texas in the United States all the way to Uruguay. In the U.S., they are classified as an endangered species.
Ironically, however, on the island of Cozumel, they are viewed not as a species in need of protection, but as an unwanted threat. This is because the presence of ocelots on the island as an invasive predator poses a potential risk to native wildlife, including the West Mexican chachalaca, Cozumel white-footed mouse, the Cozumel harvest mouse, the Cozumel rice rat, and the Cozumel Vireo Baird.
Scientists have been conducting long-term wildlife monitoring on Cozumel since the 1990s using methods such as camera traps, line transects, road sampling, and extensive fieldwork. When reviewing camera trap footage in 2016, researchers were shocked to spot an ocelot for the first time.
This was an alarming discovery because ocelots do not occur naturally on the island. According to Dr. Luis-Bernardo Vázquez of El Colegio de la Frontera Sur-SLCL, “Before 2016, we never detected any ocelot on the island. Because we had many years of sampling before that with no records, we think the species was not present on the island before that time”. Ocelots are efficient nighttime hunters with highly developed night vision and a keen sense of smell. They are adaptable to disturbance, will walk on manmade trails, and are both good swimmers and excellent climbers.
No one knows exactly how the ocelot arrived on Cozumel, but human activity is the likely cause. Dr. Vázquez notes that “in southern Mexico, sometimes wild felids are kept illegally as pets or used in tourism attractions, so this is one possible explanation”.
Chachalacas are among the ocelot’s favourite targets in Cozumel, as given their considerable size, they make for a hearty meal.
The nasua, known locally as coatí, has also been targeted by ocelots, despite being one of the largest rodents in the Americas.Photo: Carlos Rosado van der Gracht / Yucatán Magazine
Like ocelots, boa constrictors have also become an invasive species on Cozumel, as they have also managed to exploit several environmental niches. Photo taken in captivity.Photo: Carlos Rosado van der Gracht / Yucatán Magazine- Ocelots are skilled hunters and generalist carnivores that target small, medium, and large prey, making their presence in Cozumel a growing concern.Photo: Carlos Rosado van der Gracht / Yucatán Magazine
Ocelot and the Complexities of Conservation
This situation exemplifies the complexity of conservation. A species can be endangered in one region yet ecologically damaging in another. As David Will of Island Conservation observed, “A species can be endangered in one place and ecologically damaging in another, and that requires communities to decide what future they want for their island. The real challenge isn’t the cat; it’s navigating competing conservation priorities in a rapidly changing world”.
The endemic animals that could be hunted by the ocelot have no evolutionary experience or natural defenses against such a predator. However, ocelots are not their only problem. Other introduced predators have already established breeding populations on Cozumel, including boa constrictors (Boa constrictor) and margays (Leopardus wiedii). There is evidence that a small number of boa constrictors were released on Cozumel approximately 50 years ago. While these snakes are classified as vulnerable in their native range, they have been identified as a significant threat contributing to the decline of the Cozumel raccoon population, as well as the Cozumel harvest mouse and the Cozumel white-footed mouse.
The presence of ocelots in Cozumel presents a particularly striking conservation paradox. The first record of Cozumel in 2016 (a juvenile female) indicates that at least 30 individuals were documented between 2017 and 2024, confirming an established, widespread population.
The long-tailed macaque (Macaca fascicularis), like the Ocelot in Cozumel, is a conservation paradox across Southeast Asia. Although it is officially listed as endangered due to habitat loss and the pet trade, in some locations it has become an invasive species. Introduced or overpopulated in fragmented forests, these macaques raid crops and outcompete native wildlife for resources.
Senior Editor Carlos Rosado van der Gracht, PhD, is a journalist, photographer, and expedition leader. Born in Mérida, Carlos holds degrees from universities in Mexico, Canada, and Norway. Most recently, he earned a doctorate in Heritage Studies in 2026.
