Trade in exotic pets is big business. Adding to the number 

of snakes that are captive-bred in the United States for this 

purpose, nearly 112,000 Burmese pythons (Python molurus bivittatus) 

were imported since 1990. In recent years, more than 1,900 pythons 

have been captured in Everglades National Park (ENP) and 

surrounding areas. Park staff oversaw the removal of nearly 370 such 

snakes in 2009 alone.

Native to Southeast Asia, Burmese pythons were introduced to 

the park from captive animals that were either accidentally or 

intentionally released. Prior to 2008, anyone could walk into a flea 

market and purchase a 20-inch baby snake for just $20. Within a year, 

though, that baby could grow to 5 feet or more, a size that requires 

substantial quantities of live mice and even rabbits to maintain. When 

full grown, these reptiles could reach 20 feet or longer and weigh 

more than 200 pounds, large enough to tempt even well-intentioned 

pet owners to release their now-unwanted pythons into the wild.

Ecological Consequences

Large Burmese pythons are known to prey on a wide variety of native 

wildlife, including rodents, raccoons, rabbits, bobcats, deer, House 

Wrens, Rails, White Ibises, and Limpkins. This disruption of the 

natural food chain has potentially serious impacts to the ecosystem 

and may threaten many additional species in the very near future. 

Of particular concern is their predation of protected species we are 

attempting to recover, like the American alligator, American Wood 

Stork, and Key Largo wood rat.

Being semi-aquatic in nature, Burmese pythons are proving quite 

adaptable in the many environments of the Everglades. As they 

disperse, they vie directly with native wildlife for habitat and food. 

Pythons can easily out-compete many full-grown native snakes, 

dwarfing them even at a very young age. Bobcats and pythons occupy 

similar areas and experience a significant overlap of prey. And 

colonies of nesting birds, when disturbed by foraging pythons, may 

suffer impacts resulting from the eventual abandonment of nest sites. 

Scientists continue to investigate how native animal populations will 

be impacted as Burmese pythons spread across the landscape.

For years, park staff suspected pythons were reproducing in the 

Everglades. Numerous small hatchlings had been found that were 

unlikely to have been released by people, and several females were 

captured carrying from 30 to 50 fertile eggs. In 2006, scientists 

confirmed their suspicion by uncovering the first of several nests 

since found in the wilds of south Florida. This is of considerable 

concern, as it is believed that ecological impacts are likely to grow in 

step with continued reproductive success and dispersal.

National Park Service

U.S. Department of the Interior

South Florida Natural Resources Center

Everglades National Park 

Number of pythons removed from Everglades National Park and 

surrounding areas over the past decade. Data provided by Skip Snow, ENP

Fanciful legends of exotic snakes prowling the Everglades have persisted since the late 1800s. Today, sightings of large serpents 

in the wilds of south Florida are all too real. Nonnative Burmese pythons have become a widespread problem with over 1,900 

individuals captured since 2000.

Natural Resources Management 

Burmese Pythons

Burmese python, Python molurus bivittatus

Photo by Roy Wood, ENP

Printed on 30% post-consumer waste paper with vegetable-based inks. Fiber sourced from responsibly 

managed forests.
April 2013 • South Florida Natural Resources Center • 950 N Krome Avenue • Homestead, FL 33030 • (305) 224 - 4200

Education, Prevention, Early Detection, and Rapid Response 

Burmese pythons have already proven themselves a significant management challenge in the 

Florida Everglades, but the problem will worsen if additional species are released into the 

wild. That’s why Everglades National Park partners with a variety of federal, state, local, 

tribal, and non-governmental organizations to broadly communicate the dangers associated 

with introducing nonnative species into natural areas. In recent years, the park has helped 

develop of a variety of materials—including field guides, exhibits, online trainings, and 

school curricula—about invasive species. Fostering public awareness through education can 

be the most cost-effective strategy against unwanted species.

Though important, education alone cannot prevent the arrival of all nonnative plants and 

animals. The proliferation of global commerce presents numerous pathways for the introduction 

of foreign species, often requiring legal measures to safeguard against new invasions. The 

National Park Service supports measures recently enacted by the Florida Fish and Wildlife 

Conservation Commission to prohibit the personal possession of certain reptiles—including 

Burmese pythons. New rules recently enacted by the US Fish and Wildlife Service also 

prohibit the importation and interstate movement of these and several other large 

constrictors. And in recent years, amnesty programs have been developed to provide owners 

with a responsible means to surrender unwanted exotic wildlife without fear of penalty. 

Past experience has shown that early detection and a rapid response can help successfully 

eradicate some invasive organisms. By promptly reporting sightings of nonnative species, 

everyone can help prevent their establishment in south Florida’s natural areas.

Over the past decade, personnel have recovered over 1,900 pythons from the park and surrounding areas. Study of captured specimens gives 

us a better understanding of the biology of pythons and their impacts on the park. Scientists and park managers are currently exploring new 

methods of controlling pythons, including the use of specialized traps to aid in their capture.

Investigation & Control 

Never before have snakes this large established themselves beyond 

their natural range. Furthermore, no introduced population of 

reptiles has ever been successfully eradicated anywhere on earth. 

Thus, the unprecedented invasion of Burmese pythons in Everglades 

National Park mandates that managers investigate experimental new 

methods of monitoring and control.

It is said you should understand your enemies, and park scientists 

are trying to do just that. With funding from the Critical Ecosystem 

Studies Initiative (CESI), they have implanted large pythons with 

radio tracking devices and re-released them into the park. The goal 

is to obtain information about the behavior of these exotic snakes 

and their habitat use. By observing the tagged pythons in the wild, 

scientists have learned that these animals adapt well to a variety of 

vegetation communities. During the breeding season, these “Judas” 

animals can lead scientists to aggregations of untagged pythons, a 

challenge that would otherwise be nearly impossible to surmount in 

a wilderness area nearly twice the size of the state of Rhode Island. 

Understanding the movements and preferred habitats of Burmese 

pythons is only the first step in control. Scientists are investigating 

new methods of detecting and capturing these large, elusive reptiles. 

Efforts are currently underway to better engage field personnel and 

the general public in the visual search for, reporting of, and removal 

of pythons. Tracking dogs have proven successful in finding problem 

snakes in other parts of the world, and researchers are evaluating 

their effectiveness against pythons in south Florida. Even the use of 

thermal imagery is being investigated as a possible detection tool.

Passive methods of control are also being tested. Scientists have 

developed several potential trap designs and are currently evaluating 

the effectiveness of each. Researchers are also beginning to 

investigate the use of pheromones as a possible attractant. During 

reproduction, males are attracted to these chemical cues when 

emitted by females. In conjunction with an effective trap design, these 

chemicals may one day prove to be another useful control tool.

Though complete eradication of pythons in south Florida is unlikely, 

population control may be possible over select areas.

Photos by ENP

YOU

can help stop the 

spread of invasive species by 

reporting sightings, responsibly disposing 

of unwanted pets, and helping educate 

others! Visit

www.DontLetItLoose.org

for more information about what 

you can do.