Burmese pythons can find their way back home, even when they are moved more than 20 miles away.
If you pick them up and drop them in a new location, most snakes will move rapidly but erratically, often traveling the same terrain before giving up and settling into their new digs.
But not Burmese pythons, which have invaded and affected the food chain in Florida’s Everglades National Park and Big Cypress National Preserve. Researchers say the findings change their understanding of the snake’s behaviors and intellect.
“This is way more sophisticated behavior than we’ve been attributing to them,” says Frank Mazzotti, wildlife ecology and conservation professor at the University of Florida, based at the Fort Lauderdale Research and Education Center. “It’s one of those things where nature makes us go ‘wow.’ That is truly the significance of this.”
For the study in Biology Letters, researchers captured 12 pythons and surgically implanted radio transmitters that allowed them to track the snakes’ movements. As a control group, they returned six of the snakes to the spot of their capture and turned them loose.
The remaining six snakes were taken to spots ranging from 13 to 22 miles away from where they had been captured and turned loose. The snakes oriented themselves toward “home” and maintained their bearings as they traveled.
Map and a compass
And although it took between 94 and 296 days for five of the six snakes to get within three miles of home, partly due to it being the snakes’ dormant season, the reptiles kept that orientation—a clear signal to scientists that the snakes have both “map” and “compass” senses.
The relocated snakes appeared to use local cues at the release site to understand their position relative to home (the map sense), and appeared to use cues along the way (their compass sense) to ensure that they remained on track, although researchers don’t yet know what those cues are: smell, perhaps the stars, light, or some kind of magnetic force.
It’s helpful for researchers to know that the snakes move purposefully through their environment, but in reality, it’s not that much help, Mazzotti says. “It amps up a little bit our concern about the snakes, but given all the other things we know about pythons, the amount of increasing concern is minor.”
The Burmese python has been an invasive species in South Florida since about 2000, a situation that likely stems from accidental or purposeful releases by former pet owners. The largest python found in the Everglades area had grown to more than 18 feet.
The snakes suffocate and eat even large animals, such as deer and alligators, and in 2012, researchers found severe declines in sightings in python-heavy areas of native animals including raccoons, opossum, bobcats, and rabbits.
In 2012, the federal government banned the import and interstate trade of four exotic snake species: the Burmese python, the yellow anaconda, and North and South African python.
Researchers at the University of Missouri-Columbia and Davidson College contributed to the study.
Source: University of Florida