Ex-Pet Nile Crocs Invade Everglades, Threaten Pets

Posted by Stacey Venzel
Bernard Gagnon/Wikimedia Commons

Florida has yet another ex-pet to add to its list of invasive species--and it's the most dangerous one yet.

With a tropical habitat, the Florida Everglades provides ideal sanctuary for thousands of species, including many endangered animals. But the ecosystem also supports the survival of hardy animals that shouldn't be there; predatory animals that are not native to the area and therefore have no natural enemies.

Creatures like the deadly Nile crocodile.

Alligators thrive in the expanse of freshwater swamps in southern Florida. Saltwater crocodiles, the American alligators' cousin, are found in lesser numbers throughout brackish and marine environments of the southern U.S. But recently, freshwater Nile crocodiles have started showing up.

Tim Muttoo/Wikimedia Commons
Tim Muttoo/Wikimedia Commons

Three Nile crocs have been captured around the Miami region over the past decade, in 2009, 2011, and 2014. DNA tests confirmed they are from the same lineage as the African crocodile.

The genetic profile did not align with nearby facilities that house the animals on display, like Disney's Animal Kingdom and the animals certainly didn't migrate from their native African origin. But researchers are banking on a theory of how they got here.

It's a theory that keeps popping up among invasive reptiles in the Everglades and surrounding southern U.S. states. Burmese pythons are perhaps most well known, but iguanas and Nile monitors are also theorized to have entered the wilderness as exotic ex-pets that either escaped or were released. A Nile crocodile population only adds to the list of growing ex-pet invaders--and illegal ones at that.

This massive species--second largest among reptiles only behind the saltwater crocodile--can reach nearly one ton in weight and grow to more than 20 feet in length. While sharks fill the fearful minds of vacationing beachgoers with horror stories, fingers should really be pointed at the Nile crocodile.

On average, only six shark attacks occur worldwide each year, but up to 200 fatalities happen annually with Nile crocodiles in their much more restricted geographic range of native sub-Saharan Africa.

Hans Hillewaert/Wikimedia Commons
Hans Hillewaert/Wikimedia Commons

In addition to the implications the Nile croc's predatory prowess has for native wildlife, pets are in danger, too. Among the 50 states, Florida ranks in the top half for number and acreage of farms, with more in the southern belt nearer to the Everglades. Nile crocodiles therefore pose a risk to the plethora of regional heartland pets. But it's not just farm animals in danger.

Last year, southern Florida shattered adoption event records when 17,826 pets were adopted from shelters in the area in a single day. This means Florida has a lot of dogs, cats, rabbits, and other domestic pets wandering outside-- easy prey for a giant Nile crocodile.

Biologists are unsure if any other Nile crocodiles are roaming the waters of the Everglades, or even as far reaching as Alabama, Mississippi, Louisiana, and Texas, but they speculate that this could well be the case. They also cannot surmise how long the crocs were living in the wild before capture, but the reptiles were found in varying life stages. It is possible that a breeding pair is swimming through the swamplands unbeknownst to wayfaring pets.

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Ex-Pet Nile Crocs Invade Everglades, Threaten Pets