Florida’s Invasive Serpent: The Burmese Python

A few thousand years ago, the Kissimmee River freely trickled south over 11,000 miles of Florida’s land, creating a vast, thin sheet of water that spread over much of the state’s southern half. Over the next couple thousand years, ponds, marshes, and forests developed creating nearly half of Florida’s delicately balanced ecosystem. Four-fifths of that land eventually went to farming and development. In 1947, Everglades National Park opened in order to protect the complex ecosystem that remains.

Unlike most national parks, the Everglades was established not to protect majestic scenery, but to preserve the unique wildlife and their habitats. The area acts as a subtropical refuge for thousands of plants, animals, and insect species, which have attracted millions of curious tourists over the years to see the unique area. Many of the Everglades’ species exist nowhere else on Earth. The special climate of the Everglades combines both Northern and Caribbean climates, which creates a fragile and rare sub-tropical region. The life of these species rests in the hands of Everglades National Park, whose ecosystems remains in constant flux while park workers try to counteract changes in climate, human pressures, and reduction in air and water quality.

In addition to protecting these rare species, proponents striving to protect the park must worry about the threat of invasive species that could potentially offset the delicate balance that makes up the ecosystem in the Everglades. Pythons, the Burmese in particular, has in recent years contributed to the destruction of the ecologically unique areas within the Everglades. The Burmese Python, originally found in Southern- and Southeast Asia, was most likely introduced to Florida by an individual who illegally imported the snakes for an exotic pet trade. The Burmese Python, one of the top five largest snake species on earth, often exceeds an impressive 12 feet in length, up to nearly 20 feet and upwards of 200 pounds. Burmese Pythons also constrict their prey rather than using venomous bites, an attractive trait for exotic pet owners.

In the early 2000s, the Burmese Python either escaped into the wild or was liberated by an overwhelmed pet owner. Realizing how little effort they needed to exert in order to find prey, they started to populate their new snake haven. Mammals in particular were so plentiful in the Everglade region that Pythons, at the time of their introduction, had to put little to no effort into finding food. Preferring mid-sized mammals for their meals, the Burmese Python will still eat most anything it can swallow, assisting the python in its adaptability. Furthermore, the python adjusted extremely well to the rare subtropical climate. It took only a handful of individuals to remove a few Burmese Pythons from their native habitat and into Florida’s. Since then, the python has turned into a concerning and prominent threat to the Everglades’ ecological stability through the endangerment of several species of mammal in the park.

In the Everglades, the pythons have no natural predators, with humans acting as their only superior in the food chain. Unsurprisingly, there is not a huge human demand for python meat. Even if there were, the snakes prefer spending most of their time being virtually undetectable.  Most hours of the day are spent lounging in the warmth to preserve energy, which also enables them to wait for food. Once suitable prey comes around, they expel a large amount of energy at once in order to shock the prey before they begin their constriction. The python’s advanced hiding skills make it difficult to tell exactly how large the population of Burmese Pythons has grown. However, we can look at how much the surrounding environment has changed since their arrival in the early 2000s.

The U.S. Department of Interior suspects that the mammal population in Florida has severely declined since the millennium. Michael Dorcas, a herpetologist (amphibian zoologist) at Davidson College in North Carolina, lead a nighttime study of animals seen on Everglades’ roadways (both dead and alive) from 2011, spanning the study over an area of 35,400 miles of road. The data that his team collected provides an estimate of certain species in the area and their frequency. They compared their findings to the same study done in 1996-1997, confirming a stunning decline in animal sightings. Raccoon sightings dropped a staggering 99.3%, opossum sightings by 98.9%, bobcats by 87.5%, and absolutely no rabbits or foxes were sighted during the entirety of the study. Exactly how badly the Burmese affects the Everglades’ ecosystem is not yet clear, but disturbances in the mammal populations have magnified. Disease has been ruled out as an explanation for the diminishing of animals because disease usually only affects specific species at a time. Unfortunately, mammals of all sizes have declined in number since the early 2000s, leading scientists to point specifically at the Burmese.

As humans have observed in other areas of the planet, any large change in environment can cause a trophic cascade and disrupt food chains. For example, raccoons, a once plentiful species in the Everglades, love to eat turtle eggs. Now that the raccoon population has diminished, we may start to see the Everglades’ turtle population greatly expand in coming years.

Even though the Burmese is not selective in its diet, visitors to Everglades National Park have reported no attacks — despite the park seeing approximately a million visitors each year. However, it is not the size of visitors that turns the Burmese Python away from having a delicious human child as a snack. Burmese Pythons have been known to constrict a deer twice the size of an adult male. The pythons may stay away from humans because humans tend to travel in bunches and stay in more populated areas, while the snakes prefer solitary areas where they can remain undetected and wait for lonesome prey. Despite preferring mammals, the pythons have been known to also eat birds, fish, and other reptiles, including alligators.

A 2008 U.S. Geological survey suggests that if the issue were completely ignored, the Burmese Python could endanger regions outside of Florida State, and maybe even the southern third of the nation thanks to their undiscerning palate and their adaptability to new environments. In order to contain the population of Burmese Pythons in the Southern part of Florida, a month-long challenge was enacted where both permit-holding hunters and general public tried to capture as many pythons as possible. At the end of the month, only 68 pythons were caught statewide, which merely reiterated the fact that humans cannot match the stealthy reptiles’ hide-and-seek skills. A hunting season proved ineffective, so a different plan emerged.

In 2008, Python Patrol was launched. The Nature Conservancy trained a group of over 400 wildlife workers and volunteers to effectively and humanely capture and remove a python once spotted. Florida urges residents to call in snake sightings immediately so that trained responders can dispatch to the area of the sighting before the snake disappears. Since the snakes save most of their energy for sudden bursts to attack prey, python responders can use the snake’s lack of endurance to their advantage. They pull the snakes back repeatedly by the tail as the python expels much of its energy trying to release from the grip. The pythons quickly overexert themselves, and the trained worker can then grab the snake at the base of the head, bag it, tag it, and drop it off at a designated location for research or training of more Python Patrol members.

A law enacted by the Department of the Interior in January 17, 2012 helps prevent importation and travel of the Burmese Python, along with three other invasive snake species. Python owners who had a snake before the law came into play have the choice to turn in the snake at no penalty, or to get a state permit, microchip the snake, and adhere to proper caging regulations. The Nature Conservancy hopes such a ban will reach federal level in order to take a more preventative approach to heavily restricting the trade of potentially invasive species all together before they become established in a new region.

Realistically, nothing truly effective can be done to decrease the number of Florida’s invasive serpents. The Burmese Python has fully integrated into its new habitat, making it extremely difficult to ever completely reverse the damage. The National Park acknowledges this, and focuses their energy on containing it instead. According to a 2005 study done by Cornell University, the United States spends roughly $120 billion each year trying to fight invasive species. Studies continue to understand the snake’s migration, habitat use, thermal biology, and their true impact on ecosystems.

The bigger picture, though, is to learn from the invasion and prevent new invasive species from being introduced into foreign areas—especially vulnerable habitats such as Florida’s precious Everglades, one of the nation’s treasures. Preventative measures will be the most effective action to keep species in their original homes, along with education about how much havoc an invasive species can wreak on a foreign ecological system. It’s true that snakes may have a bad reputation—they’re scaly, they move strangely, and many people are afraid of them. However, it’s a shame that the Burmese Python is seen as the enemy after being taken out of its home then adapting flawlessly to a new area. The snakes have accomplished what every species strives to do—adapt, thrive, and repopulate. Yet, when introduced to an especially vulnerable area, the Burmese Python is the bully.

Humans have the power to introduce species to a new area, but they do not always know the implications of what could happen if they do. In order to take a step in the right direction and prevent more invasive species from developing, an increasing number of people must become aware of the problem and understand how detrimental moving a species into a foreign habitat can be, even if intentions are innocent. Even exotic pet owners who have a passion for the animals must realize that it is not only important for natural habitats stay intact, but it is also in the animals’ best interests of the animals to stay in their original home. Taking responsibility to try and preserve the natural balance of our fragile ecosystems is a commendable task, one that Florida will continue to battle. Through promoting awareness, future situations similar to the Everglades’ Burmese Python invasion could be avoided.