Burmese Python in the water in the Florida Everglades.

How Many Pythons Are In The Everglades?

One of the world's largest constrictor snakes has established absolute dominance in the Florida Everglades. While it is classified as vulnerable in its native habitat of Burma and other parts of Southeast Asia, the Burmese Python (Python molurus bivittatus) is reproducing at overwhelming rates in Southern Florida. The first invasive specimen was removed in 1979, and since then, the population has ballooned uncontrollably, suffocating the unique ecosystem as a result.

While their direct threat to humans is negligible, Burmese pythons are wiping out already struggling species of mammals and birds, and they are strong-arming the other large predators in the region out of their much-needed food sources. Wade into the swamp and unpack this bizarre situation. How many pythons are in Florida's Everglades? How did they get there? And what, if anything, can be done about it?

Burmese Pythons in the Everglades

Burmese Python in the Florida Everglades, on a tree
Burmese Python in the Florida Everglades.

Burmese pythons were first introduced into the Florida Everglades because of a combination of accidental and intentional release. Both scenarios stemmed from the exotic pet boom that began in the 1980s. While it is now illegal to own pythons as pets in the Sunshine State, between 1996 and 2006, as many as 100,000 baby Burmese pythons were imported into the United States (with Florida being the big market). Many buyers became overwhelmed as the once manageable babies grew into behemoth adults. Burmese pythons can reach 20 feet in length, with the largest individual ever recorded hitting a behemoth 23 feet. With such pronounced mass comes an insatiable appetite. A full-grown python can eat something half its size in a single sitting. In the Everglades, this translates into scores of smaller mammals, but also whole alligators, and in one case, a python was found with three deer (or what remained of them, at least) in its stomach! It is unsurprising that such creatures can escape amateur confines, and it is even less surprising that so many owners abandoned them (even though doing so is illegal). 

While exotic pets kicked off the invasion, in 1992s, Hurricane Andrew greatly increased the gene pool. The Category 5 storm destroyed a local breeding facility, thereby releasing untold more Burmese pythons into the foreign, albeit, tailor-made ecosystem. Because they are apex predators, females lay 50 to 100 eggs per year, they are expert camouflagers, and because the Everglades closely resemble their native ecosystem, the python population continues to spiral out of control.

The magnitude of the problem has been difficult to even hypothesize. The Florida Everglades, though within 30 miles of one of the country's largest cities, Miami, are themselves nearly devoid of any infrastructure. The swampy labyrinth is challenging to navigate, and despite being so large, the snakes are quite difficult to spot. Therefore, conducting a systematic survey is all but impossible. With that said, hunting figures, camera traps, modeling, and other tracking methods have produced working estimates (wide as they may vary).

Government and Media Reports

A "Wanted" sign, in Grassy Waters Natural Area, part of the Everglades eco system warning about burmese python snakes
A "Wanted" sign in Grassy Waters Natural Area, part of the Everglades, warning about Burmese python snakes. Image credit Thomas Barrat via Shutterstock

According to the United States Geological Survey (USGS), there are "tens of thousands of invasive Burmese pythons" living in the Everglades. However, Florida Fish and Wildlife put the figure between 100,000 to 300,000. The latter seems more likely as between 18,000 and 19,000 pythons have been removed or killed (usually the latter) by hunters and researchers since 2000. The South Florida Water Management District Governing Board implemented the Python Elimination Program in 2017. As of the most recent in-house estimates (June 2023), this initiative has removed 7,330 pythons (although the Washington Post claims that 11,000 have been captured under this program). Whatever the true figures are, USGS has called the Everglade invasion "one of the most intractable invasive-species management issues across the globe."

Recent media attention has leveraged the (not-quite) annual Python Challenge to pique interest in a problem that now involves much of Southern Florida, is likely to include more of the state in the future, and may even break into other parts of the South-Eastern United States. For the time being, these large-scale hunts are the best chance of tempering the rapid population growth. Given that there is a $10,000 cash prize offered to the person who kills the most pythons during this 10-day window in August, an understandable enthusiasm has emerged for the hunt. However, even seasoned trappers have expressed remorse over having to catch and kill such amazing creatures. But there does seem to be a general understanding that either the pythons are eliminated, or they will continue to kill other animals at unprecedented rates.

Ecological Impact and Management Efforts

Pythons Hatching in Florida Everglades with close up of green blades of grass
Pythons hatching in Florida Everglades.

The plethora of Burmese pythons now found in over 1,000 square miles of Southern Florida, including all of Everglades National Park and into Big Cypress National Preserve, have decimated several key populations of mammals and birds. For instance, white-tailed deer, foxes, bobcats, rabbits, raccoons, and opossums have seen declines ranging from 88% to over 99%. The domination of the food chain has indirectly impacted other large predators, such as alligators (which themselves have been killed by large Burmese pythons), and panthers. Already threatened species like the Key Largo woodrat, wood stork, and nesting colonies of wading birds, such as the limpkin, roseate spoonbill, great egret, and snowy egret, have also been negatively impacted by the python problem. As if this was not already bad enough, the growing presence of these Southeast Asian constrictors has been spreading diseases to native snakes.

The Python Elimination Program continues to expand its scope, now covering Monroe, Miami-Dade, Broward, Collier, Hendry, Lee, and Palm Beach counties, and is currently seeking new applicants to meet the increased demand. Given that humanely destroying the snakes is the most viable solution, the punctuation delivered by the Python Challenge has also become important. 2023's winner, Paul Hobbs, brought down 20 pythons (of the 209 collectively removed), earning the $10,000 grand prize. Furthermore, the state has removed almost all red tape to encourage everyday citizens to take up the fight. On private land, a hunting license is not even required.

Mass killing is not the only solution being developed and implemented. Tagging large male pythons with radio transmitters has helped researchers uncover the whereabouts of breeding females (i.e., the primary target for population management). It is thought that gene manipulation and pheromone trickery might help quell the expansion. But even with a combination of measures, given that the Burmese pythons have established a significant breeding population across a large ecosystem, and females lay between 50 to 100 eggs per year, total eradication is not considered a realistic outcome.

The cat is out of the bag, or rather, the python is out of its cage, and there is no getting it back in. The case of the Burmese python invasion of the Florida Everglades is a cautionary tale of just how out of control exotic populations can get in new viable environments. As is always the case with invasive species, prevention is vital. As of 2010, pet pythons are no longer permitted in Florida, but anyone with an unusual pet that they are no longer able to care for is asked to utilize the Florida Fish and Wildlife's Exotic Pet Amnesty Program. Furthermore, if you happen to spot an animal or plant that looks out of place (i.e., invasive), especially a python, report it immediately using the IveGot1 website, app, or hotline (1-888-IVE-GOT1).


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