Why Burmese Pythons Are So Dangerous To Florida Ecosystems

Burmese pythons have established themselves as a successful invasive species in South Florida and experts say they pose a significant risk to the state’s ecosystems. But why is this the case?

Non-venomous constrictors are among the largest snakes in the world, capable of reaching around 20 feet in length, with the Florida record being a specimen measuring 18 feet 9 inches.

As the name suggests, Burmese pythons are native to parts of Southeast Asia, but were introduced to the Sunshine State by humans decades ago.

Burmese pythons pose a significant risk to ecosystems in South Florida. One of the large constrictor snakes is pictured above.
FWC/Andy Wraithmell

How did the Burmese python get to Florida?

Burmese pythons were introduced to the state in the 1970s and 1980s when thousands of animals were imported to be sold as exotic pets.

“Burmese pythons were introduced to Florida through accidental and intentional releases via the pet trade,” said Lisa Thompson, spokeswoman for the Florida Fish and Wildlife Conservation Commission. Newsweek.

“There is a misconception about how pythons became established in Florida. Some believe that Hurricane Andrew in 1992 caused the python problem, but pythons had been detected before this hurricane, as early as 1979. Several events in Introduction probably happened in several places in South Florida,” she said.

The species is now considered invasive in the state, where it lives over more than 1,000 square miles to the south, primarily in the Everglades ecosystem but also in some of the surrounding areas, according to the US Geological Survey.

It is virtually impossible to estimate the population size of Burmese pythons in Florida because they are so difficult to detect.

“Pythons have cryptic coloring and can hide well, and even expert searchers can find only 1% of pythons that are in the area they are looking for,” said Bryan Falk, program analyst at the National Invasive Species Council. . Newsweek. “This low probability of detection remains the greatest challenge for controlling and researching invasive pythons in Florida.”

But based on the number of Burmese pythons that have been removed from Florida ecosystems, experts say there are likely tens of thousands in the state, possibly as high as 100,000 or potentially even more.

What does a Burmese python eat? And what impact does the Burmese python have on the Everglades ecosystem?

Burmese pythons have no natural predators in Florida and thrive in the southern part of the state, where they grow to large sizes, which means they can eat a wide variety of animals.

According to Falk, Burmese pythons eat more than 70 species in Florida, and they even occasionally consume alligators.

Not only do pythons eat native wildlife, but they also compete with them for limited food resources. In fact, severe declines in some small mammal populations in Florida have been linked to invasive pythons.

A 2012 study by Proceedings of the National Academy of Sciences of the United States of America (PNAS) based animal route surveys reported “severe apparent declines” in mammal populations that coincided with the proliferation of pythons in the Everglades.

“Before 2000, mammals were frequently encountered during nocturnal road surveys in Everglades National Park,” the PNAS study authors wrote. “In contrast, road surveys … from 2003 to 2011 documented a 99.3% decrease in the frequency of raccoon sightings, 98.9% and 87.5% decreases for raccoon sightings. opossum and bobcat, respectively, and did not detect rabbits.”

“The road surveys also revealed that these species are more common in areas where pythons have only recently been discovered and are most abundant outside of the python’s current range. These results suggest that predation by pythons has resulted in a dramatic decline of mammals in Everglades National Park.”

A Burmese python in the Everglades
Burmese pythons feed on a variety of native wildlife in the Florida Everglades. One of the invasive snakes is pictured above.
FWC/Andy Wraithmell

Mammals that had suffered the worst declines were often found in the stomachs of pythons. The introduction of pythons has had other negative effects on Florida’s ecosystems, experts say.

“We are only just beginning to understand the cascading effects of these and other less obvious impacts on Florida’s ecosystem,” Falk said. “One example is disease transmission. Because pythons have reduced the number of mammalian species, mosquitoes that feed on mammals now more often feed on rodents, and rodents are hosts to the Everglades virus, which the mosquito can then transmit to humans.”

The implication is that in areas where pythons are present, a person may be more likely to become ill from a mosquito-borne mammalian virus, highlighting the complexity of the impacts invasive species can have. “

Pythons are also known to have brought a parasitic non-native Asian species of pentastoma (a type of crustacean) to Florida.

“This parasite lives in the lungs and can be transmitted to native species of snakes,” Thompson said. “Recent research indicates that parasitic pentastomes are now spreading independently of pythons and have been found from Key Largo to Volusia County. Other emerging disease risks, including nidovirus, may impact native snake species, but the extent or impacts of this virus on Florida wildlife is not fully understood.”