Florida residents had enough to worry about in their waters with alligators and native crocodiles, but now comes a report that there is a new predator on the scene, according to National Geographic.  And this one is more dangerous that the native species.

Since 2000, four Nile crocodiles, which can grow to a length of more than 20 feet, have been found in Florida waters.  The good news is that none of the found reptiles were fully grown, and they have not shown any signs of reproducing in the swamps and rivers of the state.

However, Adam Rosenblatt, an expert on crocodilians, says “Nile crocodiles are generally considered to be much more aggressive than American alligators or American crocodiles.”  Rosenblatt, a postdoctoral associate at the Yale School of Forestry and Environmental Sciences, adds, “But I think we do need to take this seriously,” he says. “We’ve all seen what can happen with unchecked invasions, like the Burmese python.”

In that case, the pythons are contributing to the disappearance of the rabbit population in the Everglades, reported to be responsible for 77 percent of the rabbits’ deaths.  Officials suspect the pythons started out as pets and either escaped or were released into the wild.

Although the source of the Nile crocodiles is not confirmed, scientists believe these new predators arrived in the area the same way as the Burmese pythons.  There have been several legal importations of Nile crocodiles in the last 10 years, notably as display animals in amusement parks, such as Disney’s Wild Kingdom.  It is likely these invaders were involved in the pet trade, and their owners found they were too much to handle.

Genetic testing on the animals revealed that at least tow were closely related to Nile crocodiles usually found in South Africa, and possibly a third was from the same area.

Despite the similarities, the Nile crocs have fewer offspring than their American cousins, according to Abby Lawson, a Ph.D. candidate at Clemson University’s Department of Forestry and Environmental Conservation.  She adds that will make it harder for the reptiles to establish a population in Florida.

Experts say there is no reason to worry about Nile crocodiles in the waters of the state.  At least no more than the other crocs and alligators who were already here.

Photograph by Beverly Joubert, National Geographic Creative