OOS 5-10 - Invasive pythons reshape the Everglades mammal community

Monday, August 8, 2016: 4:20 PM
Grand Floridian Blrm H, Ft Lauderdale Convention Center
Brian E. Reichert, Wildlife Ecology and Conservation, University of Florida, Gainesville, FL, Robert A. McCleery, Department of Wildlife Ecology and Conservation, University of Florida, Gainesville, FL, Adia Sovie, Wildlife Ecology and Conservation, University of Florida, Kristen Hart, USGS, Rena Borkhataria, Doris Duke Conservation Scholars Program at UF and Robert Reed, US Geological Survey
Background/Question/Methods

Burmese pythons have been an established invasive predator in the Greater Everglades Ecosystem (GEE) for at least 20 years. Recent studies suggest that Burmese pythons are clearly linked to recent declines in native marsh rabbits (Sylvilagus palustris) and there is some anecdotal evidence suggesting that pythons may be causing declines of other meso-mammals throughout the GEE. However, there are a host of additionally factors that might explain the declines of mammals in the GEE. In particular, the GEE has seen increased human development, habitat changes and drastic alteration in water flow all of which could influence the shape of meso-mammal communities. We are interested in elucidating the drivers the changing meso-mammal community across the GEE. Using trip cameras and scat searches we sampled 113 randomly placed plots throughout the GEE. We then constructed a multispecies occupancy model to assess the biotic and abiotic factors influencing the species distributions and community structure of meso-mammals in the GEE.

Results/Conclusions

Python density had significant negative effects on all observed species except coyotes for which the effect was also negative but not significant based on credible intervals over-lapping zero. Species richness was lowest near the epicenter of the python invasion where estimated python densities are the highest in the region. Based on our results, python density had significant negative effects on local species richness and severely altered community composition. The python induced loss and change to meso-mammal communities across the GEE is probably causing a massive rearrangement of the food web, losses in ecosystem function, and complex and unpredictable cascading effects.