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Congress weighs ban on importation of pet pythons

Prompt action is needed at the federal level to limit the number of invasive pythons released into the wild, South Florida Water Management District (SFWMD) Deputy Executive Director George Horne said in written testimony to the U.S. Congress today. The House of Representatives Subcommittee on Crime, Terrorism and Homeland Security is considering a Bill that...

Prompt action is needed at the federal level to limit the number of invasive pythons released into the wild, South Florida Water Management District (SFWMD) Deputy Executive Director George Horne said in written testimony to the U.S. Congress today.

The House of Representatives Subcommittee on Crime, Terrorism and Homeland Security is considering a Bill that would classify nonnative pythons, such as the Burmese python, as “injurious animals” and ban their importation into the United States.


Hypothetical diet necessary for a hatchling Burmese python to reach 13 feet in the Florida Everglades (approximately 5 to 7 years)

1 raccoon
1 oppossum
4 five-foot alligators
5 American coots
6 little blue herons
8 ibises
10 squirrels
15 rabbits
15 wrens
30 cotton rats
72 mice

This illustration and the photos on this page were appended to the SFWMD written testimony handed to Congress today.

(Source: Skip Snow, Everglades National Park & Dr. Stephen Secor, University of Alabama)

“As a top predator and prolific breeder, these exotic snakes threaten state and federal efforts to restore America’s Everglades, and they prey on the natural wildlife that call the Everglades home, including species already threatened or endangered,” SFWMD’s Horne said in the agency’s testimony to Congress.

“We have a long history of successful invasive plant management and experience, but only recently have we had to commit more and more resources to the emerging populations of the Burmese python and other nonnative constrictors appearing across our landscape.


“If effective preventative programs were in place to limit introductions of nonnative constrictors, such as the legislation now under consideration, these much-needed taxpayerfunded resources could be redirected to other important resource management efforts.

“Today, however, the negative impacts from the unlimited importation of new pest animals require active responses on our part. Effective prevention of additional introductions of potentially invasive constrictor snakes, as proposed in this Bill, is the only path to prevent these costs from continually increasing.”

While Florida, California and Hawaii are among the states most impacted by introduced invasive species, every state is affected, Horne added.

Photo of Burmese python killed in Florida courtesy of SFWMD

“Globally, exotic invasive species, including pest animals, weeds and pathogenic diseases, are a major cause of global biodiversity decline. In particular, nonnative animals compete for food and habitat, upset existing predator/prey relationships, degrade environmental quality, spread diseases and, in our case, may threaten the integrity of flood protection levees and canal banks, and electrical power delivery.

“Nationally, more than 50,000 species of introduced plants, animals and microbes cause more than $120 billion in damages and control costs each year. Already, 192 nonnative animal species are established in Florida, calling for the development of methods to forecast and respond to the potential economic loss, environmental damage and social stress caused by both new nonnative animal introductions and long-established invasive organisms,” Horne said.


The Bill before Congress makes an important contribution towards prevention by limiting the importation of two snake species (the Burmese and African pythons) with high invasion potentials in the U.S., Horne said.

“The amendment could also be expanded to include all giant constrictor species determined by the U.S. Geological Survey (USGS) to have medium or high invasion risk potential. The recently published USGS risk assessment for giant constrictors ranked nine species as having either a medium or high overall risk potential for invasion in the United States.

“These species include the Beni Anaconda, boa constrictor, Burmese python, DeSchauensee’s anaconda, green anaconda, northern African python, southern African python, reticulated python, and yellow anaconda.”

Photo of Burmese python killed in Florida courtesy of SFWMD

“We strongly support inclusion of these species in [the Bill] in order to immediately limit importation of species that our best science predicts will be invasive,” Horne added.

“Rather than wait for the next Burmese python to become established in the United States, a proactive approach such as the proposed legislation being discussed today is urgently needed to protect our environment, economy and quality of life–not just in Florida but throughout the nation.”

The South Florida Water Management District is deeply committed to preserving and restoring South Florida’s environmental health and, unfortunately, the Everglades ecosystem is now home to the invasive Burmese python, Horne said.


Fifty-two eggs were inside a 16-foot Burmese python found in May, 2009 by South Florida Water Management District officials south of the Tamiami Trail in Miami-Dade County, Florida.

Photo courtesy of SFWMD

The snake is a top predator that is known to prey upon more than 20 native Florida species. Notable among these are the federally listed Key Largo wood rat, white-tailed deer, American alligator, bobcat and numerous wading birds common to the Everglades, including the wood stork.

“Attempts to manage Burmese pythons divert taxpayers’ funds from these other urgent primary restoration and protection tasks. Yet, failure to do so will leave this aggressive animal as a serious impediment to our Everglades restoration progress,” Horne said.

Small livestock likely prey

The Burmese python also threatens agricultural interests as small livestock are also likely prey, Horne added.

Since 2000, the South Florida Water Management District and Everglades National Park have removed 1,248 Burmese pythons from the Everglades.

“Experience already gained in Florida strongly indicates the need to regulate the importation and sale of this snake. Without stronger regulation and control resources, adverse impacts of Burmese pythons will continue to get worse, and the python’s population will continue to expand north of the Everglades and likely into South
Florida’s urban areas.”


Burmese python nest eggs found in Miami-Dade County in Florida

Photo courtesy of SFWMD

Florida’s other nonnative giant constrictors

Given South Florida’s abrupt boundaries between dense human population centers and vast subtropical wilderness areas, it comes as no surprise that numerous giant constrictor species have been observed in Florida, Horne said.

“While most observed animals are presumed to be released pets, three additional constrictor species are now considered established or potentially established in Florida–the common boa, northern African python and yellow anaconda.

“All three species are identified in the USGS risk assessment as having a high overall risk of establishment in the
United States. The common boa has been repeatedly observed in South Florida, primarily on the Deering Estate in eastern Miami-Dade County, but also near Everglades National Park.

“Between 1989 and 2005, 96 common boas were captured in South Florida.

“Recent confirmed sightings of northern African pythons near the eastern boundary of the Everglades and yellow anacondas near Big Cypress National Preserve and Myakka State Park in southwest Florida are also cause for alarm.”

“Recent confirmed sightings of northern African pythons near the eastern boundary of the Everglades and yellow anacondas near Big Cypress National Preserve and Myakka State Park in southwest Florida are also cause for alarm. All three of these species share traits with the Burmese python that are considered important factors for invasive potential, and like the Burmese python all three species will be very costly to control should they become widely established.”


Burmese python photo courtesy of South Florida Water Management District

As the South Florida Water Management District and other agencies try to contain the documented damage and growing threat of the Burmese python and other invasive animals in Florida, the flow of potentially harmful exotic animals across U.S. borders continues, Horne said.

“To use just one example, roughly 144,000 boa constrictors were imported into the United States between
2000 and 2007. Federal action is needed now to address the immediate threat posed by giant constrictors which have or are likely to establish in our nation’s wilderness areas.”


This map from the recently published USGS risk assessment for giant constrictors suggests how much of the United States has a climate suitable (green area) for the establishment of the Burmese python.

Map courtesy of USGS

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“National Geographic Explorer: Python Wars” airs in the United States on February 9, at 10 p.m. on National Geographic Channel. Click on the video above to watch an excerpt. Click here to view more excerpts and get additional information.

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Author Photo David Max Braun
More than forty years in U.S., UK, and South African media gives David Max 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. In his 22-year career at National Geographic he was VP and editor in chief of National Geographic Digital Media, and the founding editor of the National Geographic Society blog, hosting a global discussion on issues resonating with the Society's mission and initiatives. He also directed 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. A regular expert on National Geographic Expeditions, David also lectures on storytelling for impact. He has 120,000 followers on social media: Facebook  Twitter  LinkedIn