Changing Planet

Python Invasion of U.S. Unlikely, New Study Says

python 2.jpg

Giant snakes may not be about to invade much of the United States, after all. 

One of the more dire predictions of the consequences of climate change came from the U.S. Geological Survey (USGS) a few months ago: The giant Burmese python currently wreaking havoc in the Florida Everglades could find itself “comfortable” in as much as a third of the nation once temperatures rise as projected.

A new study using a different computer model released this week suggests otherwise. Climate change will actually seriously impact the current range of the reptile in the U.S., confining it to the swampy southern fringe of Florida.

Read more and see a snake “climate match” map and pictures in the extended entry.

The Burmese python is one of the largest snakes in the world, growing as long as 25 feet and weighing as much as 200 pounds. Thousands of the snakes have been imported into the U.S. as pets.

Since a breeding population of the python was first discovered in the Everglades five years ago, the snake has been found in other places across Florida. Pythons were most likely introduced into the Everglades by owners wanting to get rid of them.


An American alligator and a Burmese python in a death struggle in Everglades National Park. Alligators don’t always prevail in these encounters.

Photos in this entry by Lori Oberhofer: Courtesy National Park Service

The USGS model released in February compared projected rainfall and temperatures across the U.S. with the climate conditions of Burmese pythons in their native habitat in Asia. The computer model generated the map below, suggesting that as many as 32 states would be suitable for the snakes by the year 2100.



Projected climate in the continental United States in the year 2100, based on global warming models, that matches climate in the pythons’ native range in Asia.

Image courtesy USGS

But new calculations using many more climate factors produce a different picture.

“The results of the [new] models suggest that the pythons are restricted to the vicinity of the Everglades in extreme south Florida, so while wildlife authorities will have their hands full dealing with established populations of these snakes, people outside of Florida should not fear an inexorable northward expansion,” said a statement released by the City University of New York (CUNY) yesterday.

“Far from flourishing under potential scenarios of global warming, the snakes are predicted to be seriously impacted by models of global climate change, a fate which is likely not unique to the pythons,” the statement continued.

In other words, the climate of the continental U.S. will likely keep the snakes in the Everglades.

“Snakes already get an unwarranted bad reputation,” said Frank Burbrink at the College of Staten Island/CUNY, who was involved in the new study. “The last thing needed in our current biodiversity crisis is to drum up more hatred of these animals by suggesting an impending full scale North American invasion by pythons when properly constructed climate models suggest the opposite.”

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Forty years in U.S., UK, and South African media gives David Braun global perspective and experience across multiple storytelling platforms. His coverage of science, nature, politics, and technology has been published/broadcast by the BBC, CNN, NPR, AP, UPI, National Geographic, TechWeb, De Telegraaf, Travel World, and Argus South African Newspapers. He has published two books and won several journalism awards. He has 120,000 followers on social media. David Braun edits the National Geographic Society blog, hosting a global discussion on issues resonating with the Society's mission and initiatives. He also directs the Society side of the Fulbright-National Geographic Digital Storytelling Fellowship, awarded to Americans seeking the opportunity to spend nine months abroad, engaging local communities and sharing stories from the field with a global audience. Follow David on Facebook  Twitter  LinkedIn

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