Florida’s Burmese Python Invasion

Marques Hayes


In June 2021, Florida announced a contest for hunting Burmese pythons in the Everglades, the 2021 Python Challenge which resulted in the removal of 223 pythons. This year, the Florida Python Challenge is scheduled to run from August 4 to 13, 2023.

To understand why Burmese pythons are hunted in Florida, one must first understand the role biogeography plays in allowing invasive species to thrive in the state.

Biogeography is about the distribution of flora and fauna in terms of its geography. Geography often shapes where plants and animals can be found, even within short distances. Ecology, biology, climatology, and geography are just a few subjects that are involved within biogeography.

Burmese pythons are listed as an invasive species in the state of Florida. An invasive species is a non-native species that has a negative influence on the ecosystem that it has been introduced to.

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As its name suggests, the Burmese python is native to the country that used to be known as Burma (its name was changed to Myanmar in 1989). In addition to the country of Myanmar, the Burmese python is found other parts of Southeast Asia, namely Vietnam, Cambodia, Laos, Thailand, and parts of Indonesia. Burmese pythons are also found in Bangladesh and southeastern China.

A Burmese python coiled in the grass in the Everglades.
A Burmese python coiled in the grass in the Everglades. Photo: Bryan Falk, USGS. Public domain.

Introduction of the Burmese python to Florida

Although Burmese pythons have been found in Florida since the 1990s, the first report of established populations in the Everglades National Park was recorded in 2000. They are known for eating local species, causing a drop in the number of native species. Burmese pythons also compete with native wildlife species for food.

Pythons negatively impact location biodiversity in Florida

A 2012 study found declines of mammal populations that coincided with the introduction of the Burmese Python.  Observations of raccoon populations had decreased 99.3%, opossums 98.9%, and bobcats 87.5 percent since 1997.   Other mammals such as cottontail rabbits, marsh rabbits, and foxes have all but vanished.

A Burmese python slithers through the grass in the Florida Everglades. Photo: Emma Hanslowe, USGS, public domain.
A Burmese python slithers through the grass in the Florida Everglades. Photo: Emma Hanslowe, USGS, public domain.

The negative impact the Burmese python has on Florida’s wildlife is only one of the invasive species causing problems. The state of Florida is a major hub for invasive species. There are at least 500 species of flora and fauna that are invasive within Florida. Florida’s own geography is a major factor. 

Mapping the spread of pythons in Florida

In 2023, USGS Ecologist Jacquelyn Guzy led a team of researchers that synthesized Burmese python research and developed a map showing the progression of the snake’s invasion of southern Florida between 1979 and 2001.

A map with a gradient from yellow to magenta showing the spread of the Burmese python in southern Florida.
Researchers from the USGS mapped out the spread of the Burmese python in southern Florida between 1979 and 2021. Map: USGS, public domain.

In this study, the researchers noted that surveying pythons to understand population numbers and densities is challenging because of low detectability as a result of their secretive behavior and coloration that provides camouflaging. To develop a more comprehensive map of the reach of the python in Florida, researchers resorted in part to using the results of environmental DNA, the bits of genetic material shed through skin, feces, mucous, and decomposing flesh.

1979 (noted on the map) marks the first sighting of a python, a 12-foot snake that was run over on Tamiami Trail in the Florida Everglades. It wasn’t until 1995 that the first documentation collection of pythons by biologists in Florida occurred.

The python has continued to push the boundaries of its expansion north along the peninsula of Florida. According to the USGS, there are now recordings of pythons in West Palm Beach, the southern end of Lake Okeechobee, and areas north of Fort Myers — represented on the map as the deep magenta band of expansion from 2019-2021.

Why do pythons thrive in Florida?

The climate of Florida makes it an optimal place for invasive species to thrive. Northern Florida has a humid, subtropical climate. Its winters are warmer than most of the United States of America. Southern Florida has a tropical savanna climate as well as tropical monsoon climate. Why is climate such an important factor? 

It is imperative to understand some of the invasive species that make their way to Florida. It is also imperative to understand the origin of such species. As mentioned earlier, the Burmese python has its origins in Southeast Asia. Other invasive species that have turned up in Florida include the black spiny-tailed iguana, green anaconda, and yellow anaconda.

Invasive black and white tegu lizards (Salvator merianae) found in Florida. Photo: USGS, public domain.
Invasive black and white tegu lizards (Salvator merianae) found in Florida. Photo: USGS, public domain.

Florida is a major center for the exotic pet trade. This often includes reptiles that are not native to the United States. Such reptiles originate in the tropical regions of Central and South America, Sub Saharan Africa, and Southeast Asia. Species such as the Burmese python are proven to thrive in Southern Florida. The Burmese python’s native habitat has a similar climate to Southern Florida. Climate is only one part of the problem.

A Lack of Natural Enemies

One major issue with invasive species comes from the lack of natural enemies. This is often the case for many invasive species that have ended up in Florida. The Burmese python is a very large snake. Citing of these snakes as large as 17 to 18 feet long have been found.

Because of its size, the Burmese Python has very few natural enemies. In the case of the Burmese python, only people are alligators would pose a threat to it. In fact, Burmese pythons have been known to eat alligators. Because of the lack of natural enemies, the Burmese python has been able to proliferate and outcompete the local wildlife in Florida. 

An American alligator and a Burmese python battle in the Florida Everglades National Park.  While this snake appears to be losing the battle, many pythons have either escaped or eaten alligators in Florida. 
An American alligator and a Burmese python battle in the Florida Everglades National Park.  While this snake appears to be losing the battle, many pythons have either escaped or eaten alligators in Florida. Photo: Lori Oberhofer, National Park Service. Public domain.

These factors and the inherent biology of the python have contributed to the establishment of the python in Florida. Female Burmese pythons can lay between 50 to 100 eggs at a time.

Florida’s location has a major role to play in the exotic pet trade. The state of Florida extends further south than any other state within the contiguous 48 states. This is where geography becomes strategic for the exotic pet trade. The city of Miami, near the far southeast corner of Florida, is home to one of the busiest ports in the United States of America.

Miami is closer to Central America and South America than most major port cities in the USA. Miami is the closest major port of entry for trade between the United States of America and Latin America. This is also a major port of entry for exotic animals being transported to the United States. 

Some people enjoy having exotic pets. Some facilities were breeding pythons in addition to exporting them. Some people decided they couldn’t care for such animals any longer. When this occurs, many exotic animal owners release their animals into the wild.

Hurricane Andrew also played a devastating role. Hurricane Andrew was a particularly destructive hurricane, hitting the Miami area in 1992. Many homes were destroyed, as well as a facility that bred Burmese pythons. This allowed Burmese pythons to get into the wild. Miami is located close to Everglades National Park. 

Everglades National Park consists of tropical habitats including mangroves, swamps, and marshes . The Everglades is also home to tropical hardwood hammocks.

A tropical hardwood hammock is a type of tropical forest consisting of a mix of evergreen trees and deciduous trees. This type of forest is found in the southern Florida and parts of the Caribbean region.

Hammocks interrupt the flat sawgrass expanse as seen from the Mahogany Hammock boardwalk in Everglades National Park.
Hammocks interrupt the flat sawgrass expanse as seen from the Mahogany Hammock boardwalk in Everglades National Park. Photo: Heather Henkel, U.S. Geological Survey. Public domain.

Pineland forests and coastal lowlands are included within the park as well. What makes Everglades National Park unique is that it is the largest tropical national park in the in United States of America. For many tropical birds, the park serves as a place for breeding. Only in the Everglades does the American crocodile and the American alligator co-exist

The Everglades region is particularly harmed by the Burmese python where it’s estimated that tens of thousands of these snakes exist. The Burmese python now inhabits over a thousand square miles of southern Florida, including the entire Everglades National Park and areas to the north such as Big Cypress National Preserve and Collier-Seminole State Forest.

Efforts are being made to trap and remove Burmese pythons from the state of Florida in order to reduce this invasive specie’s deleterious effect on native wildlife. Florida Fish and Wildlife Conservation Commission and South Florida Water Management District have contributed by paying people to trap pythons. In Florida, it is legal to kill a Burmese python, as it is considered an invasive species.

In February 2021, the Florida Fish and Wildlife Conservation Commission voted to ban 16 invasive species from Florida including the Burmese python. It is now illegal to bring Burmese pythons into Florida.  

Florida’s battle with the Burmese python, however, is just one aspect of the invasive species problem. Intensive efforts will be needed to combat the invasive species. It starts with education, and stricter laws regarding species allowed in Florida. 

The python hunting contest is a part of the effort to rid Florida of this invasive snake while also raising awareness about invasive species and the threats they pose to Florida’s ecosystems. In June of 2023, two hunters captured a 19-foot Burmese python in South Florida’s Big Cypress National Preserve.

The 125 pound python was declared to be the longest ever caught and was donated to the Conservancy of Southwest Florida in Naples, Florida. The heaviest recorded python was a female weighing 215 pounds that was caught by Conservancy research in June of 2022


Brasileiro, A. (2021, February 23). Florida wants to stop these reptiles from becoming the next invasive species in the Everglades. Phys.org – News and Articles on Science and Technology. https://phys.org/news/2021-02-florida-reptiles-invasive-species-everglades.html

Dorcas, M. E., Willson, J. D., Reed, R. N., Snow, R. W., Rochford, M. R., Miller, M. A., … & Hart, K. M. (2012). Severe mammal declines coincide with proliferation of invasive Burmese pythons in Everglades National Park. Proceedings of the National Academy of Sciences109(7), 2418-2422. https://doi.org/10.1073/pnas.1115226109

Guzy, J. C., Falk, B. G., Smith, B. J., Willson, J. D., Reed, R. N., Aumen, N. G., Avery, M. L., Bartoszek, I. A., Campbell, E., Cherkiss, M. S., Claunch, N. M., Currylow, A. F., Dean, T., Dixon, J., Engeman, R., Funck, S., Gibble, R., Hengstebeck, K. C., Humphrey, J. S., … Hart, K. M. (2023). Burmese pythons in Florida: A synthesis of biology, impacts, and management tools. NeoBiota80, 1–119. https://doi.org/10.3897/neobiota.80.90439

Harvey, R. G., Brien, M. L., Cherkiss, M. S., Dorcas, M., Rochford, M., Snow, R. W., & Mazzotti, F. J. (2008). Burmese Pythons in South Florida: scientific support for invasive species management. EDIS2008(4). https://journals.flvc.org/edis/article/view/117278/115392

How have invasive pythons impacted Florida ecosystems? (2019). USGS.gov | Science for a changing world. https://www.usgs.gov/faqs/how-have-invasive-pythons-impacted-florida-ecosystems

Mikell, M. (2016, January 8). Because of pythons, nine lives may not be enough for Florida panther • The national wildlife Federation blog. The National Wildlife Federation Blog. https://blog.nwf.org/2012/02/because-of-pythons-nine-lives-may-not-be-enough-for-florida-panther/

Ramírez, J. (2021, July 9). Why Miami is the nation’s commercial office gateway to Latin America. Ideas. https://www.wework.com/ideas/workspace-solutions/flexible-products/miami-usa-gateway-to-latin-america

This article was originally written on September 9, 2021 and has since been updated.


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About the author
Marques Hayes
Marques Hayes is a GIS Analyst and a freelance geography writer. He has a Bachelor's degree in geography. Geography is a subject that Marques has a special interest in.