Researchers have found evidence that feral cats are invading farms and killing juvenile Cuban crocodiles, a critically endangered species.
Two biologists reported that feral cats killed a total of 145 juvenile Cuban crocodiles during the fall of 2022. This is a concerning issue because the Cuban crocodile (Crocodylus rhombifer) is an extremely endangered species that only resides in the Zapata Swamp and Lanier region of Cuba, as reported by Live Science on May 10.
Juvenile Cuban crocodiles released into water in August 2022. (Photo: Reuters).
Some distinguishing features between the Cuban crocodile and other American crocodile species include a bony ridge behind the eyes, an aggressive or curious temperament, and the ability to leap high out of the water, according to George Amato, honorary director of the Comparative Genomics Institute at the American Museum of Natural History and an expert on Cuban crocodiles. The Cuban crocodile represents a very ancient evolutionary branch and plays an important role in its natural ecosystem. Amato has been studying this species since the 1990s.
It is estimated that only about 3,000 Cuban crocodiles remain in the wild, prompting efforts to increase their population. Each year, the Zapata Swamp Crocodile Breeding Farm, the largest breeding facility for Cuban crocodiles in the world, releases 500 crocodiles into the swamp, hoping they will grow and reproduce, according to Etiam Pérez-Fleitas, a biologist collaborating with the farm.
From October to November 2022, the farm managed approximately 4,500 Cuban crocodiles, which experienced a series of predation attacks resulting in the deaths of 145 four-month-old crocodiles, according to a report in the journal Herpetology Notes. Pérez-Fleitas and Gustavo Sosa-Rodriguez described evidence that feral cats were responsible for the attacks, including suspicious tracks and fur collected nearby.
Camera traps also recorded images of at least one feral cat entering the crocodile enclosure. On one occasion, farm staff witnessed several feral cats feeding on something nearby. Upon investigation, they discovered pieces of crocodile meat. Additionally, the attacks ceased one month after seven feral cats were captured and removed from the area.
Both Amato and Pérez-Fleitas emphasized that juvenile crocodiles are not kept in large numbers in confined areas in the wild. Therefore, the new findings indicate that wandering feral cats could cause damage in the environments they invade. Ranked 38th among the world’s 100 worst invasive species, it is estimated that feral cats kill billions of birds and mammals in the United States each year. To prevent harm to native ecosystems, some organizations and governments have implemented controversial measures, including trapping, shooting, and distributing poison.
Pérez-Fleitas and colleagues are monitoring areas where Cuban crocodiles exist to estimate the feral cat population. If the numbers are small enough, male cats may be sterilized to protect the crocodiles.
