September 2006 Archives

Stephen Secor - Associate Professor, University of Alabama Exploding python – Awakening gator A 13-foot Burmese python, bloated and dead, was found in the Everglades National Park on September 26, 2005. There was a large gash in its side and from it protruded a 6-foot alligator. Helicopter Pilot Mike Barron and Wildlife Biologist Skip Snow discovered the creature within a creature. Photographs of the discovery flooded my email. I’ve been studying the digestive physiology of snakes for 15 years now, but I’d never seen a case like this one. It looked like the python had eaten the alligator, but then why was the python dead and half of the alligator exposed? CSI: Everglades Mike, Skip, and I returned to the crime scene with National Geographic’s Explorer to find out what happened. At 200 feet and at 50 mph, I was getting a bird’s-eye view of the new residency of the Burmese python within the Everglades, a landscape of tall grass, small tree islands, and the occasional “gator hole.” We taped off the scene and brought out the photos Mike took the day of the initial discovery. With the laminated photos laid out on knee-deep water, Skip and I pieced together the possible series of events leading to the death of both animals. Myths busted There had been two theories – but both seemed unlikely. Gas (caused by the decomposing alligator) built up inside the python’s stomach causing the snake to combust. Or the python consumed the alligator while it was asleep, the alligator awoke inside the python’s stomach, and the alligator was clawing its way out of the python’s stomach when both expired. Having worked on hundreds of Burmese pythons of all different sizes, I could not imagine that enough gas would have been produced by the decomposing alligator to cause a rupture in the very thick skin of the python. I have seen pythons after consuming very large meals expand to four times their diameter without any damage to their skin. From the photograph of the dead python, it appeared that the python may have only doubled in width due to the alligator meal. Also, like humans, pythons can pass excess gas from their stomachs. As for the awaking alligator scenario, this would require that the alligator was not dead, but only unconscious when swallowed by the python. Pythons kill their prey by constriction and only eat once they have sensed that the prey is dead. On the chance that the alligator was not dead and regained consciousness inside the python’s stomach, it would have quickly succumbed to the lack of oxygen. In addition, with its hind limbs pinned tightly against its tail within the snake there would have been no room for the alligator to maneuver its feet and claw through the python. There are two types of animals in the world: snakes and snake food Can a Burmese python even constrict, swallow, and digest an alligator? While there are no published accounts of Burmese pythons in the wild eating crocodilians, we know that two other of the world’s giant snakes are able to so. There are accounts and photographs of anacondas in South America feeding upon caimans and a record of an African rock python constricting a Nile crocodile. Considering the list of formidable prey items that pythons are known to consume including leopards, wild pigs, impala, gazelles, porcupines, and pangolins, it is not unreasonable to suspect that they can also digest an alligator. With the photographic evidence from the Everglades that the Burmese python can kill and swallow an alligator, members of my research laboratory and I set to see how well a python could swallow an alligator and how long it would take the snake to digest the alligator. From our colony of Burmese python we enticed an 800 gram snake to swallow a 200 gram alligator, already dead. To our surprise, the python easily swallowed the alligator, taking only about 15 minutes to do so. Each day after the python had swallowed the alligator we transported the snake to a local veterinary clinic and X-rayed the snake’s midsection. The X-rays revealed clearly the daily disintegration of the alligator’s skeleton, first the skull, then the shoulder regions and forelimbs, followed by the pelvic region, hindlimbs, and tail, all completed within nine days. So, not only can a Burmese pythons swallow an alligator, it can also digest it. There goes the neighborhood: What are pythons doing in the Everglades? Why are there now Burmese pythons in the Everglades anyway and how will they impact the native animals? The first part of this question can be answered in two words, size and climate. Burmese pythons are one of the largest snakes in the world, able to exceed 20 feet in length. They were also the first python to become very popular in the pet trade due to their docile nature, ease of maintenance and breeding, and the development by snake hobbyists of several different color variants. Bred and sold by the thousands each year as hatchling for almost two decades, the young pythons with their voracious appetites simply grew too big for many homes. Manageable at first in a 20 gallon aquarium on a diet of mice, a 4-year old Burmese python (12 feet in length), requires a very large cage and has graduated to a diet of rabbits. Unfortunately as these snakes grew too big, they were taken out to the countryside and released to fend for themselves. As a result, medium and large pythons have been discovered wandering the suburbs, woodlands, and countryside across the United States. With much of North American having a colder or a drier climate compared to the subtropical native home of the Burmese python, many of the released snakes were unable to survive through the year.