Big Problem in the Big Easy: Invasive Cuban Treefrogs Move into Louisiana

Louisiana is now home to one more frog species, and that's a problem. According to Popular Science, scientists have found invasive Cuban treefrogs at a New Orleans zoo, marking the first toehold the amphibians have been able to make in the U.S. outside of Florida.

Cuban treefrogs are native to Cuba, the Cayman Islands, and the Bahamas, but they came to the U.S. in the 1920s by way of the Florida Keys. They have since spread as far north as Jacksonville. The massive frogs—females can grow up to 6 inches long—are major pests, hunting several species of native Floridian frogs and out-competing others, clogging drains and setting up camp in toilets, and occasionally causing power outages when they decide to hide in utility boxes.

Now, the species is showing up in New Orleans, more than 430 miles away. They may have stowed away on a 2016 shipment of palm trees from Lake Placid, Florida bound for the elephant exhibit at New Orleans's Audubon Zoo.

A U.S. Geological Survey in the fall of 2017 captured hundreds of the frogs on and around the zoo's grounds. Over the course of four surveys, USGS scientists found 367 frogs and 2000 Cuban treefrog tadpoles. They drained the two pools where the tadpoles were swimming in the hopes of killing off any they missed, but the likelihood of reversing the spread of the frogs is low. The USGS warned in a recent press statement that "eradicating the recently discovered population in Louisiana is improbable." The frogs reproduce quickly and will eat almost anything. Based on the results of these surveys, it seems they have already driven out all the native frogs in Riverview, the section of Audubon Park where the tadpoles were found.

Brad Glorioso, the lead USGS ecologist on the study, explained that while stowaway treefrogs have trouble surviving when they make their way to higher latitudes, the climate around New Orleans seems to be more hospitable to them. "They often end up in places with unsuitable climates, but in south Louisiana, Cuban treefrogs appear capable of withstanding seasonal cold spells by seeking appropriate refuge," he said.

For now, the best scientists can hope for is keeping the frogs from moving across the river from the zoo into one of the large public nature preserves nearby.