In Ecology News: Python vs the Everglades

Are exotic pythons devastating Florida’s Everglades National Park? By Liza Lester, ESA communications officer Sometimes the snake wins. The exotic Burmese python is a new and deadly predator allegedly squeezing the wildlife of Florida’s already environmentally pressured Everglades. Large snakes have been observed swallowing American alligators and 80-pound deer, but more common prey are small mammals like raccoons, rabbits, and ‘possums, which have been disappearing. Credit, Lori Oberhofer, National Park Service. ________ A WAXING population of Burmese pythons has suspiciously paralleled waning sightings of native critters in Florida’s Everglades, says a paper out this week in the Proceedings of the National Academy of Sciences. Following on the tail of an announcement two weeks ago (Jan 17th) that the U.S. will ban imports and interstate sales of the exotic python and three other large constrictor snakes (yellow anacondas and northern and southern African pythons), the story has been attracting plenty of media attention. The case against the python is not a slam dunk, but the authors amass circumstantial evidence of its guilt in connection to the missing native fauna, and legislators are buying it. [See: EcoTone, 21 Sep 2011, “Deregulation of protections against invasive species can have dire long-term economic consequences.”] Burmese pythons (Python molurus bivittatus) are native to the warm latitudes of Southeast Asia, and arrived in Florida as pets. The python has an eclectic appetite, dining on more than forty varieties of evergladian mammal, bird and reptile, including other carnivores, endangered species, and the occasional alligator. Visitors and rangers have sighted pythons in the park for thirty years, but the park only began to view them as a resident population in 2000. A short decade later, the python had risen to the disreputable distinction of “conditional reptile,” and was officially blacklisted. Hopes that the cold winter of 2010 would kill off the pythons have been disappointed, as Terence explains in Tuesday’s EcoTone post. In July 2010, Florida Fish and Wildlife forbade acquisition of new pythons, required grandfathered owners to microchip their pets and obtain a license, and instituted a permitting system for civilian python hunting in the public parks. The US has imported 112,000 Burmese Pythons since 1990, according to the US Fish and Wildlife Service. Owners have been known to release their sinuous darlings after the snakes, which can reach almost 20 feet, grow too large to cohabitate comfortably in the house. But park managers speculate that the 1992 category 5 storm Hurricane Andrew may be the primary source of the python population explosion. An internal Fish and Wildlife study found little genetic variation in the python population—a sign of a small, closely related foundling group. “At...

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