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the snake that ate Florida


I know this is all over the news, but I thought it might be good to go to the source of the information.

Severe mammal declines coincide with proliferation of invasive Burmese pythons in Everglades National Park

  1. Kristen M. Hartj

+ Author Affiliations

  1. aDepartment of Biology, Davidson College, Davidson, NC 28035;
  2. bDepartment of Fish and Wildlife Conservation, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061;
  3. cFort Collins Science Center, US Geological Survey, Fort Collins, CO 80526;
  4. dEverglades National Park, National Park Service, Homestead, FL 33034;
  5. eFort Lauderdale Research and Education Center, University of Florida, Davie, FL 33314;
  6. fDepartment of Biological Sciences, Auburn University, Auburn, AL 36849;
  7. gState Museum of Pennsylvania, Harrisburg, PA 17120;
  8. hDepartment of Biology, Denison University, Granville, OH 43023;
  9. iCenter for Forest Sustainability, Auburn University, Auburn, AL 36849; and
  10. jSoutheast Ecological Science Center, US Geological Survey, Davie, FL 33314
  1. Edited by Peter M. Vitousek, Stanford University, Stanford, CA, and approved December 21, 2011 (received for review September 26, 2011)


Invasive species represent a significant threat to global biodiversity and a substantial economic burden. Burmese pythons, giant constricting snakes native to Asia, now are found throughout much of southern Florida, including all of Everglades National Park (ENP). Pythons have increased dramatically in both abundance and geographic range since 2000 and consume a wide variety of mammals and birds. Here we report severe apparent declines in mammal populations that coincide temporally and spatially with the proliferation of pythons in ENP. Before 2000, mammals were encountered frequently during nocturnal road surveys within ENP. In contrast, road surveys totaling 56,971 km from 2003–2011 documented a 99.3% decrease in the frequency of raccoon observations, decreases of 98.9% and 87.5% for opossum and bobcat observations, respectively, and failed to detect rabbits. Road surveys also revealed that these species are more common in areas where pythons have been discovered only recently and are most abundant outside the python's current introduced range. These findings suggest that predation by pythons has resulted in dramatic declines in mammals within ENP and that introduced apex predators, such as giant constrictors, can exert significant top-down pressure on prey populations. Severe declines in easily observed and/or common mammals, such as raccoons and bobcats, bode poorly for species of conservation concern, which often are more difficult to sample and occur at lower densities.