A Python Takeover

Sometime over the past few decades, Burmese pythons began appearing in Everglades National Park in south Florida. The snakes were most likely either pets that had been released into the wild or their descendants, and, like countless tourists before them, they took very well to the tropical heat and lush greenery of Florida. Predation from the Burmese pythons is already changing the delicate balance of the national park's food chain. Scientists from the University of Florida, the U.S. Geological Survey and the Florida Fish and Wildlife Conservation Commission released 26 marsh rabbits fitted with tracking devices into the park. The aim was to find out what effect the pythons would have on the rabbits, which are native to the Everglades but have all but vanished over the past decade—the same period of time when sightings of Burmese pythons became more frequent. In the fall and winter, the marsh rabbits thrived, reproducing rapidly. But when the weather began to warm—which would have made the temperature-sensitive pythons more active—the marsh rabbits began to disappear. Where? Into the bellies of the Burmese pythons. The snakes hunted the rabbits ruthlessly—the researchers found that 77% of the tracked rabbits were eaten by Burmese pythons, a fact scientists knew because the trackers led them to the digested bodies of the rabbits inside the stomachs of the snakes. (At a control area outside the park, by contrast, no rabbits were killed by pythons, and most that died were eaten by native mammals like bobcats.) So voracious were the Burmese pythons that they essentially hunted the marsh rabbits to the point of extinction.