Creature Feature: Burmese Pythons Prowl the Everglades, and That’s Not a Good Thing
Breeding populations of Burmese pythons have been established in extensive areas of Florida. In vulnerable places like Everglades National Park, limiting the growth and spread of this ecologically disruptive and potentially dangerous invader will be a very daunting task.
The Burmese python (Python molurus bivittatus) is a large constrictor native to the rain forests of Southeast Asia. Because it’s got attractively patterned skin, has a generally docile disposition, and is fairly inexpensive to purchase (about $70), it’s been imported in fairly large numbers here in the United States. It is thought that there are at least 5,000 pet pythons in Florida alone.
Pythons can be difficult to manage in captivity, especially if they are large and poorly kept. Over the years, many of these pet pythons have escaped or been intentionally released into the wild by owners who no longer want them.
Breeding populations have been established in the wild in Everglades National Park and are thought to exists in various other parts of Florida as well. Florida's warm climate is similar to the one that this rain forest species was designed by nature to inhabit.
We don’t want Burmese pythons living wild and free in America. We don’t want them loose in places where they can get at our pets. We don’t want them lurking near our children. We don’t want them living in our national parks and competing with the native predators for food and space.
However, unless we do something to prevent it, it’s only a matter of time before all of these things will be true in at least one-third of the 48-state U.S. They are already true in parts of Florida, including Everglades National Park.
There is a good reason to be concerned about Burmese pythons living in the wild here in America.
The Burmese python is an impressive animal, and that is an understatement by several orders of magnitude. The Burmese python is the world’s sixth-biggest snake species. A python continues to grow all of its life, and it’s not unusual for a fully mature Burmese to weigh 150 pounds and stretch 16 to 18 feet in length. The largest ones on record are much bigger than that.
A captive Burmese python living at the Serpent Safari Park in Gurnee, Illinois, is the largest living snake on record. Tagged with the unlikely name “Baby,” this enormous reptile is 27 feet long and weighs just over 400 pounds. (If you’ve got a tape measure that will reach all the way out to 27 feet, run it out there and see if that doesn’t make you glad that damn thing isn’t on the loose!)
The Burmese python is not just fast growing and long-lived (typically 20 years or so in the wild), it’s also an efficient predator. And as they get bigger these snakes gain the ability to take down and eat ever larger animals. A good-sized python can kill a water bird, a piglet, a fawn, a raccoon, a bobcat, a dog, a child. A whopper is as big around as a telephone pole and can kill and eat a pig, a goat, a deer, a good-sized alligator, a man.
Pythons kill by constriction. In practical terms, this means that they bite their victim and hang on with their sharp, backward-facing teeth while they coil their powerful bodies around the animal and squeeze it until it dies from suffocation.
It’s a bad way to go. Every time the victim exhales, the snake takes up the slack, preventing the intake of a full breath. There is no escape.
The size of the prey that pythons manage to swallow is a constant source of amazement. The secret is in the amazingly stretchy ligaments in the python’s jaws. A python’s jaws aren’t hinged in the manner of human jaws. The python’s jaws just spread further and further apart as the teeth work the victim further and further back. No chewing necessary; the victim is just swallowed whole.
This thing is on the loose in America. Although breeding populations are thought to exist only in Florida at this time, the Burmese python is capable of surviving and reproducing in about one-third of the 48-state U.S. The southern tier of states from Florida to east Texas are in the bullseye right now, and a warming climate, coupled with the species’ already proven adaptability, portends an even larger potential range.
Wildlife biologists are working on a strategy to slow and perhaps reverse the spread of this invasive species, but it’s an uphill task. There are lots of things this snake does that makes it difficult to deal with.
For example, young pythons spend most of their time in trees. Have you ever tried to spot pythons up there in the branches? On the ground the darn thing blends in so well with its surroundings that it can be extremely difficult to spot from only a few feet away. That’s disconcerting. The Burmese is also an excellent swimmer and can cross water bodies of substantial size. Did you know that a python can remain submerged for as long as half an hour?
And boy, are they ever prolific. Females lay clutches of 30-50 or more eggs and guard them for several months. Only a small fraction of the young snakes survive to adulthood, but that’s still a lot of snakes.
The NPS has been dealing with pythons in Everglades National Park for quite a while, and the pace is picking up. The first one, a road-kill on U.S. 41, was discovered 30 years ago, and by the 1990s about a dozen a year were being found. The first baby python was discovered in 1995. The first clutches of python eggs and already hatched nestlings were discovered around three years ago. Python sightings in the park now run to about 250 a year.
Much publicity attended the October 2005 discovery of a 13-foot python in the park that had swallowed a six-foot long alligator. Swollen and sluggish during the digesting of this hefty meal, the python was killed and partially eaten by another gator.
No one knows how many pythons there are in the park at the moment. Some estimates based on presumed densities run into the thousands, but that's little more than a guess.
We’ll have more to say about pythons in Everglades National Park and measures being developed to control them. It's an interesting story in itself.
Postscript: Is an anaconda invasion on the way too? One of these big water loving snakes has been discovered already in Big Cypress National Preserve.
Traveler trivia, no extra charge: About 60 million years ago, a snake of nightmare proportions prowled the tropical forests of northern South America. Dubbed Titanoboa cerrejonensis by paleontologists, this 42-footer (imagine that!) dined on crocodiles and other large prey. It’s still the largest snake species ever discovered.