Caimans thrive in Rio’s toxic waters
Alligator-like reptiles not a human threat
RIO DE JANEIRO, BRAZIL — Oh, the glories of Rio that await spectators and athletes at the 2016 Olympics: Those beaches, that music, the dramatic mountains. And then there are a few thousand alligator-like creatures slithering through sewage-like lagoons.
Some 5,000 to 6,000 broadsnouted caimans live in fetid lagoon systems of western Rio de Janeiro, conservationists say, and there’s a chance that visitors could have an encounter with one, though experts hasten to add that the caimans, smaller and less aggressive than alligators or crocodiles, are not considered a threat to humans.
Some of the reptiles have already taken refuge in ponds being built inside the Olympic golf course, which abuts a once pristine mangrove-filled lagoon that’s now thick with tons of raw sewage pumped from nearby high-end condominiums.
In fact, with two decades of anarchic growth decimating natural habitats, the hardy caimans have become an increasingly common sight in the urban heart of western Rio, drawn in part by the scraps tossed to them by humans.
The district is the main hub for 2016 Games and site of the Olympic Village, though most events will take place indoors. One exception is the golf course, where some caimans have taken up residence in lakes. Wildlife on golf courses isn’t uncommon, with alligators spotted on greens in Florida and kangaroos bounding around those in Australia.
“When you have a natural green space like this it attracts the wildlife, which is what you want,” said Antony Scanlon, executive director of the International Golf Federation. He said the risk to Olympic players and spectators is minimal and added that the construction company building the course has hired a reptile specialist to help manage the animals.
The caimans congregate in a canal in the affluent Recreio dos Bandeirantes suburb that’s sandwiched between two busy thoroughfares. Beachbound mothers with toddlers in strollers, neighbours out to walk the dog and pizza delivery boys pause on a narrow wooden footbridge over the canal to observe the caimans, whose brown colour camouflages them in the brackish, sulphuric waters.
With few fish surviving in the polluted waters, caiman increasingly rely on handouts from humans. They also feed on birds and the sewer rats that emerge from the culverts.
“Caimans are like tanks, a very old species with a remarkable capacity for renovation that allows them to survive under extreme conditions where others couldn’t,” said Ricardo Freitas, an ecology professor who runs the Instituto Jacare, or the Caiman Institute, which aims to protect the reptiles. “But the fact of the matter is that their days are numbered if things don’t change drastically.”
With a population that’s 85 per cent male, a serious demographic problem is looming for Rio’s caimans, said Freitas, who suspects that the uncontrolled release of raw sewage is behind the gender imbalance. Organic matter raises water warmer and among caimans, high temperatures during a certain stage of incubation result in male offspring.
While a few caimans wander from the canal, sometimes getting hit by cars, Freitas said he is aware of only one other person attacked by a caiman, a fisherman who was superficially bitten after stepping on one.