Eradicating Everglades Pythons Will be a Formidable Task

It's open season on pythons in Florida. NPS photo.

Interior Secretary Ken Salazar recently announced that the National Park Service and other federal agencies will be stepping up efforts to eradicate Burmese pythons from the Everglades. If this can be done, and that’s a very big if, it will take teamwork, technology, hard work, and good luck.

When a pet Burmese python got loose and killed a Florida toddler asleep in her bed last month, the spotlight of national media attention shone brightly on a development that has alarmed wildlife managers and public safety officials in South Florida. The Burmese python, a big, non-native snake with a well-deserved reputation for being ecologically disruptive and dangerous, has become well-established in the Everglades and the South Florida urban periphery. By some estimates, there are at least 100,000 free-roaming pythons in the Everglades already. Left unchecked, this population will swell to many times its present size.

That’s most emphatically not a good thing. Because pythons can grow very large (up to 20 feet or so) and will eat virtually any creature smaller than they are, they have the potential to wreak havoc on the Everglades ecosystem, especially the Water Conservation Areas, Everglades National Park, and Big Cypress National Preserve. Examinations of python stomach contents have revealed the remains of mice, cotton rats, wading birds, possums, raccoons, small alligators, and deer.

Pythons pose a lethal hazard to pets, smaller livestock, and people. Dogs and cats are routine fare wherever the snakes can get at them. And as the tragic death of that little girl showed last month, even a relatively small python (this particular one was only around eight feet long) can kill a child. By the time a python reaches maturity at around 12 or 13 feet, it is quite capable of squeezing the life out of an adult human. A 20-footer is one of the more lethal killing machines that nature has ever devised.

Small wonder that federal officials have decided to put python eradication on the fast track. Historians of the future will surely ask why it took so long. Significant numbers of Burmese pythons were already on the loose in South Florida by the mid-1990s. Some pet pythons went free in the chaos of Hurricane Andrew (1992). Many others escaped from inadequate enclosures or were intentionally released by owners who no longer wanted them.

Now pythons are breeding rapidly and colonizing new areas in South Florida. The question is how to kill them in large enough numbers, and quickly enough, to lessen their impact and slow their spread.

Let’s be honest about this. Eradication is much too strong a word for the end game. Killing every last free-roaming python in South Florida is just a pipe dream. The appropriate word is control, and while that term is subject to legitimate differences of interpretation, we have a general idea of what it means in the case at hand.

We don’t want to merely keep the python problem from getting worse than it is now, though that alone would be a praiseworthy achievement. What we really hope to do is reduce the free-roaming python population of South Florida to the “ecologically extinct” level – that is, to numbers so low that the species cannot play a significant role in ecosystem functioning. We’d then be dealing with nuisance pythons here and there, not pythons by the hundreds of thousands causing serious problems in geographically widespread areas.

How to bring about this sharp reduction in python numbers remains an open question. Scientists and wildlife managers are using and developing a variety of policies, tactics, and strategies. These include:

• Using partnerships to develop, implement, and coordinate python control efforts. The National Park Service has already partnered with the U.S. Fish and Wildlife Service, the U.S. Geological Survey, the Florida Fish and Wildlife Conservation Commission, the South Florida Water Management District, the University of Florida, and the Savannah River Ecology Lab, to name just a few collaborators.

• Conducting research designed to develop and improve methods for locating and capturing or killing free-roaming pythons. Scientists are performing necropsies to learn more about the python diet, radio-tracking captured pythons to learn more about their movements, mapping python captures and sightings to learn more about their distribution, testing various kinds of python traps and baits, designing airborne devices for detecting pythons, and performing myriad experiments yielding new, potentially useful information.

• Disseminating information about pythons and python control methods. Workshops and hands-on demonstrations in the field are two time-proven methods for doing this. Harnessing the Internet to the needs of this campaign will speed things up considerably.

• Making it easy for people to report the location of any free-roaming pythons they encounter. The NPS already has a python hotline that the public can use to report python sightings on parklands.

• Using rapid response teams to deal with python problems that demand urgent attention. A key tactic is to stamp out new infestations while they are in the incipient stage, “nipping them in the bud” before they can explode beyond control. The NPS is already working with the FWS, the USGS, and state natural resource management agencies to insure that invasive animal rapid response and control teams are properly trained and equipped to deal with pythons.

• Developing reliable methods for locating pythons. Many pythons are dispersed in densely vegetated or remote areas (such as mangrove forests) and are so well camouflaged that they may be difficult to spot from just a few feet away. One low-tech method is to use dogs specially trained to find pythons. Another low-tech method is to look for them along roads, paths, canal banks, and other open areas where these cold-blooded creatures go to find sunshine and warmth. A promising high-tech method employs small remotely-operated airplanes equipped with heat sensors that can detect pythons.

• Expanding the python capture program in Everglades National Park. The NPS has used experienced volunteers (authorized agents) to help capture many of the more than 350 pythons removed from the park in recent years. Training more people to find and capture pythons should increase the capture rate proportionately.

• Using baited traps to capture pythons. Capturing pythons in traps baited with attractants such as python pheromones may be especially appropriate in areas that have heavy concentrations of pythons (you can efficiently capture a lot of them) and in peripheral areas not yet colonized (you can detect threats early-on and perhaps establish a barrier to further spread). Prototype traps and lures must be tested under a great variety of field conditions.

• Encouraging licensed hunters to shoot pythons they encounter in the normal course of hunting. Few hunters have any qualms about killing pythons. This is basically a matter of removing any remaining legal impediments to the killing of these non-game animals on federal, state, and private lands. A pilot "Partner with Hunters" Program has already been developed for Big Cypress National Preserve.

• Paying bounties to people who capture or kill free-roaming pythons. The Florida Fish and Wildlife Conservation Commission is already operating a pilot bounty permit system, but it remains to be seen whether it is appropriate for national parks and other federal lands.

• Promoting responsible exotic pet ownership. People continue to release pet pythons into the wild when they no longer want them. The NPS has worked with other federal and state agencies to distribute educational materials and place signage reminding the public that releasing pythons and other exotic pets is a crime. Staging non-native pet amnesty days (typically sponsored by a zoo or wildlife sanctuary) offers an alternative to releasing unwanted pythons into the wild.

It will be interesting to see whether and how quickly the “broad partnership and multiple strategies” approach to python control in South Florida will work.

Postscript: About 60 miles from where I am sitting, there is a “snake pit” enclosure at the Savannah River Ecology Lab (SREL) in which a team of scientists from the National Park Service, the U.S. Geological Survey, and the University of Florida has released seven Florida-captured Burmese pythons. The scientists want to know whether the sterilized, microchipped, radio-tagged, snakes (some of which are more than ten feet long) can survive this far north. I don’t need to wait for the results. I’m already very confident that these buggers will find a way to handle South Carolina’s sissy winter and come out the other side just as fat and happy as they went in. South Carolina, Georgia, North Carolina, Alabama, Mississippi, Louisiana, Arkansas, East Texas, and Tennessee are all places where pythons can be expected to eventually take up residence.


One step to limit people from releasing non-native species such as the Burmese Python into the wild would be to make it very difficult for people to acquire breeding animals. If the pet stores or licensed breeders could only sell sterilized animals to the public then that would of course slow any spread of snake , in this case, colonization. It is not a cure but a step in the right direction. Understand, I don't claim to be an expert and this is just an idea.

In 2007 Florida passed legislation that named the Burmese python, four other large constrictors, and the Nile monitor lizard as "reptiles of concern.” In January a new Florida law went into effect establishing that python owners must obtain $100-a-year owners’ permits and have microchip IDs installed under the skin of their python pets so they can be owner-identified if they end up lost, strayed, or stolen. BTW, the albino Burmese python that killed the little girl in Sumter County, Florida was reportedly unlicensed.

In an earlier article on "How Big Pythons Can get" I posted a link to video footage of a 50 foot Burmese Python in captivity. It's head is as big as a medium sized dog! My comment didn't get past the moderator however since it directly conflicted with his ridiculous assertion that there were only 40 foot Pythons even back in the day of Prehistorically huge animals. Therefore, I won't bother going to the trouble of finding the link this time since this post probably won't make it past this "throwback to the days of Stalin"-style moderator (but you can Google "50 foot Python" to find it readily enough). Enjoy your life controlling everyone's access to the truth there Mr. Moderator! As long as history agrees with you right?

I don't want to shift the subject, but based on the prior comments, I am beginning to conclude that their are only 2 answers to every control issue. License and ban. For us to be successful in any endeavor, we must stop wasting resources by simply piling on more laws and procedures that must be followed. This approach feels like we are doing something, however, the number 1 law is that you do not release exotic animals into the wild. Anyone willing to break that rule, would be willing to break any other rule put into place. All of the new rules will only waste resources on getting the people who would be responsible anyway to jump through more hoops. This does not stop the irresponsible ones. Sure there are some responsible owners, who accidentally loose their snake, but that number is most likely so small that it is irrelevant. Much like the similar issues with gun control, every dollar that is spent and every minute that is spent, tracking, licensing, controlling, legitimate owners, is time and money that is not going to eliminate the bigger problem. 1 person in an office processing forms and collecting money, would be much better spent in the field working on capturing, and killing the snakes.

Anonymous No. 1, can't say I ever recall anyone offering video footage of a 50-foot python, but we wouldn't intentionally delete that. Heck, that'd draw traffic in herds! Now, if we could root out that Stalinesque moderator, we'd feed him to that python of yours.

There's a back story to the SREL experiment to see if male pythons can survive South Carolina winters.

In 2008 a couple of USGS scientists published a peer-reviewed paper on the potential range of pythons in the US:
Rodda, G.H., C.S. Jarnevich, and R.N. Reed. 2008. What parts of the US mainland are climatically suitable for invasive alien pythons spreading from Everglades National Park? Biological Invasions. Published online 27 February 2008 via SpringerLink,

A herpetologist who owns pet snakes filed a complaint under the federal data quality act, claiming that the USGS analysis used climate & habitat from the entire range of the pythons in SE Asia, while the introduced snakes in Florida might be from only a small part of that range, and thus may have overestimated the area where the pythons could become a serious problem, and thus possibly resulting in restrictions on python ownership. The back & forth was only interesting if you need to know about the data quality act (which I did): the complaint is that the USGS scientists didn't analyze data that they don't have and that don't exist. Before limitations on ownership are enforced, one side or the other should fund the genetic research to determine exactly where the snakes in Florida came from (a former colleague of mine is just the person to do that work: he's done it for snakeheads & other introduced invasive species).

But, the simpler, more direct empirical experiment is to see whether some of the snakes from the Everglades can survive winter freezes, and SREL just happened to have suitable habitat enclosures from when it was a substantial ecological research laboratory run by the University of Georgia on the DOE Savannah River Site, and thus was a very inexpensive way to perform the initial experiment.

As for rules, I agree with Anonymous that rules applied to the general public will be ineffective, as even a low percentage of scofflaws will be enough to continue the problem. However, in the case of exotic invasive species, laws targeting the importation and commercial sale of species that might cause substantial harm can be effective. We already have those rules and quarantines for health & agricultural risk, and they (mostly) work. It takes research to minimize the restrictions on the pet & horticultural trades and pet owners & gardeners while stopping potential problems at the bottleneck where they might be stopped.

Conversely, Anonymous's suggestion of one more person out hunting snakes (or even hundreds more) won't put a dent in their increase & spread. There are too many of them spread over too large of an area and they reproduce too quickly.

Just in the interest of facts, no snake has ever been measured (with anything even approaching authenticity) over 30 feet. There is a standing $50,000 reward offered by the New York Herp Society for anyone producing evidence of a live snake measuring over 30 feet. The reward has been around for many years now and has never been claimed. The "50 footer" wasn't even a Burmese, it was a Reticulated Python - a completely different species. And most snake people that look at the pictures estimate it to be about 25 feet long. Still probably big enough to eat a Stalinesque moderator, though.

Well blow me down! Them varmints lied to me!! After reviewing said footage of 50 foot "reticulate" python, I did see an ornery notion to hide the length of that thang. So I hunted down the expose column that had to be out there somewhere and yes, the good 'ol UK Guardian sent a man out with a measuring tape to verify that thang. Trouble is, he ended up so deep in the quagmire of Indonesian giant snake story tellin', he became unable to discern truth from fiction himself anymore and fell under the spell of the Shaman priest who made up the whole story in the first place... his story is weirder than the original article.
Read it yourself:,%203604,%201116074,%2000.html

I'll be volunteerin' meself to body shuvlin' detail at one of Stalin's gulag's now. ta ta...

The longest snake is currently the reticulated python at 33 feet. The footage of the 50ft snake was proven to be a hoax and that snake was actually only 22ft. I researched it extensivly when I wrote the curriculum guide for Everglades.

Ranger Holly

All I can say is I hope Florida gets this under control.I live in South Carolina and the idea of seeing something like this in my back yard makes me HORRIFIED!!! These snakes should be banned.There is no excuse for anyone to have a pet like this.And what you are seeing in the everglades now is the proof.I also have seen stories that show Florida has every kind of venomous snake in the world running loose because of all the snakes nuts who let them get out, or release them on purpose.It is so ridiculous! Cobras,gaboon vipers,pythons.It makes no sense to me why this has been allowed to go on unchecked for so long.Now it may be too late to stop the snake's progress to other states.Thanks alot,Florida.

I have heard that in the Glades there are a wide variety of non native snakes and other reptiles and amphibians, including, Indian cobras, Gaboon Vipers, Puff Adders, even Russel Vipers, now mind you giant constrictors make news, let someone get bit by a Russels viper, and watch the news coverage. Most the above mentioned reptiles were inadvertantly released by Hurricane Andrew.

More layers of regulation and future study...
There should be an outright ban on the animal and anyone caught having one should be heavily fined.
Any snake found in the wild should be slaughtered. I've lived in Guam and the place is devoid of natural life except for a few other invasive species such as the english sparrow and man.
Putting microchips under the skin of a snake which then escapes and eats an endangered species just doesn't make sense.
What kind of a pet can a python make anyway, there are plenty of good dogs and cats which by the way, make great companions are available in just about every city and town in this country.
There is no place for exotics in this country...

I was just on line and saw the price of rattlesnake meat at $40lb and higher. The bounty idea is good buut why not make it profitable for the hunters? Snakeskin is a highly sought after "leather'. Snake meat can be used for food or pet food or fishing bait. Bones can be pulverized for fertilizer.
The time for "if" studies is over. These snakes are wiping out most of the Everglades wildlife.

In regards to some of the comments that large constrictors should be banned I would like to say I keep large constrictors and I do it responsibly the snakes that are taking over Florida were not released by their owners they were released by hurricane Andrew those who keep and love our snakes should not be punished for an act of nature that damaged holding facilities that housed snakes while I am posting this I am holding a reticulated python and they are not monsters they are beautiful creatures that can be kept safely if you know what you are doing I do believe they should do something to stop the python spread in Florida but that should have been done years ago after hurricane andrew not now once they have set up breeding populations that mistake is on florida's government not on the people who keep these beautiful snakes.