Cute, cuddly, deadly

With the Teenage Mutant Ninja Turtle (TNMT) movie, Mutant Mayhem, releasing a few months ago, red-eared sliders are back on the market in Chennai. After all, who doesn’t love Leonardo, TNMT’s protagonist, modelled on a red-eared slider. We’ll tell you who doesn’t love them — the rest of the aquatic species in Chennai’s lakes in Chengalpet, Velachery, Perumbakkam and Pallikaranai marsh that are under threat from the turtle, included in the International Union for Conservation of Nature’s list of the world’s 100 most invasive species.
The Indian Wildlife Protection Act, 1972, lists the red-eared slider turtle as a Schedule IV animal, which means it is illegal to keep, trade, or transport it without a permit.Ironically, it is the world’s most commonly traded reptile. About 12 were rescued in Chennai over the past two years and housed at the Guindy Children’s Park.
The flourishing exotic pet trade in Tamil Nadu has resulted in animals such as the red-eared slider invading the local ecosystem. “Every environment has a prey and a predator. But for an exotic, there are no predators and that’s what helps them proliferate,” says parasitologist Sreekumar Chiru Kandoth, head of wildlife science at Madras Veterinary College.
In Kerala, zoonotic diseases have emerged because of invasive species. In 2020, 12 people died in Kozhikode, infected by the Shigella bacteria; eight children in Kochi were infected by eosinophilic meningitis. Both Kerala cities had two invasive species — red-eared slider turtles from Mexico that host shigella bacteria and the African giant snail that carries Angiostrongylus cantonensis worms.
“We found a correlation between those infected by meningitis and the African giant snail,” says Dr T V Sajeev, chief scientist of the nodal centre for Biological Invasions at the Kerala Forest Research Institute. “However, the health department didn’t investigate to find if there was a link with red-eared slider turtles.”
It’s a global problem, says Kandoth. “In Florida’s Everglades, Burmese pythons, sold as pets, harbour pentastomines, a parasite that infects local snakes and humans.” Supriya Sahu, additional chief secretary, environment, climate change & forests, says Irulas from TN were sent to Florida to resolve the issue. “We are working on curbing unregulated trade.”
Sajeev says the problem worsens if people abandon exotic pets or when they outlive owners. “The animals, especially reptiles, are let into lakes and local forests. Their impacts have not been studied in India.”
With the pet trade shifting from birds to reptiles, the threat of zoonotic diseases looms, says Shekar Niraj, TN biodiversity board’s member secretary.
“It begins as a mild rash or fever. People may not be aware they are infected by bacteria from their reptile pet. But it can easily turn life-threatening,” says Sreekumar. Kerala is the only state to relate an epidemic to an invasive species and adopt a prevention policy. The fight against the giant snail menace was one of the first to be operationalised under the state’s One Health umbrella.
Besides impacting biodiversity, invasives are a threat to the local economy. About 500 types of crops in Kerala including taro, ginger, spinach and plantain were destroyed by African grey snails. They also stick to concrete platforms absorbing calcium making walls fragile.
Jaro Mendoza Roldan, assistant professor at Università degli Studi di Bari Aldo Moro, Italy, says European states have banned certain species of snakes. “Reptiles are known to be sources of salmonella, a bacteria that children under the age of five and people that have some type of immune disease can be affected,” he says, adding that New Zealand and Australia euthanise animals seized at the airport so they do not enter the ecosystem. “There are shoot-at-sight orders for certain species of snakes in Europe that were earlier part of the pet trade,” says Roldan. Kandoth says as a precautionary measure, his students are developing a kit to sterilise exotic pets, especially reptiles so if they are let into the wild, the impact is not so catastrophic. “But it’s a work in progress.”
(The writer is a former journalist based out of Chennai. This article was produced with support from Internews’ Earth Journalism Network)