Huge, man-eating crocodiles may be hiding throughout the Florida wilderness, according to a study published last month in Herpetological Conservation and Biology. The Orlando Sentinel reports that DNA testing on three young crocodiles caught between 2009 and 2014 confirmed them to be Nile crocodiles native to Africa. Nile crocodiles can grow up to 18 feet long and weigh as much as a car, according to a press release. They eat everything from hippos to humans and are believed to be responsible for up to 200 human fatalities a year in Africa. The Florida Everglades have long proven to be a haven for nonnative species—including the Burmese python and Cuban tree frog. “Here's another one," study co-author Kenneth Kysko says. "But this time it isn't just a tiny house gecko."
Researchers say the Nile crocodile could thrive in Florida, which is bad news for the already tenuous ecosystem in the Everglades. Nile crocodiles could eat and mate the smaller and less-aggressive native alligators and crocodiles out of existence. Not to mention what they could do to livestock and human populations. Analysis of one of the captured Nile crocodiles—it grew 28% faster than Nile crocodiles in Africa—showed they can thrive in Florida. And researchers believe there are likely more living in the Everglades. It's unclear how the Nile crocodiles got to Florida. As their DNA doesn't match up with Nile crocodiles at Disney's Animal Kingdom and other attractions, it's most likely they are escaped pets. "They didn't swim from Africa," Krysko tells the Sentinel. (Read more crocodile stories.)