COS 277-3 - Effect of relative sea level rise on wildlife habitat in the Lower Florida Keys

Abstract: The Lower Florida Keys have unique flora and fauna, and house specific wildlife species, including Florida Key deer (Odocoileus virginianus clavium), Lower Keys marsh rabbits (Sylvilagus palustris hefneri), and silver rice rats, that are not found elsewhere. All these species reside in an especially vulnerable habitat, as the area comprises several island/complexes which exhibit flat terrain and low elevation. Considering accelerated increases in relative sea levels, there is a compelling need for predicting the impact of sea level rise on vegetation and the wildlife habitat of the Lower Florida Keys. Timely prediction will help wildlife researchers and policy makers to take appropriate conservation management actions.



This study’s objectives, therefore, were to use four different Intergovernmental Panel on Climate Change (IPCC) sea level rise scenarios (RCP 2.6, RCP 4.5, RCP 6.0, and RCP 8.5) to (1) evaluate the potential impact of rising sea levels on vegetation (and Key deer habitat) on No Name Key, Florida, and (2) estimate the change in Florida Key deer population relative to the impact of the sea level rise on the affected vegetation under each of the IPCC scenarios.



The methodology involves lidar derived elevation data and a vegetation map with six different categories. Using a lidar derived Digital Terrain Model (DTM), we determined the area of six different vegetation types at the current sea level. Then, using four different sea level rise prediction scenarios (IPCC 6^th assessment), we estimated the new area of the six vegetation types. We then predicted deer population numbers supported within each of the four sea level rise scenarios.



The results indicate less upland vegetation (i.e., pinelands and hammocks) left in the study area after applying any of the four sea level rise scenarios. Since Key deer prefer upland vegetation/areas, we conclude that the habitat affected by sea level rise will support a smaller number of Key deer.



Considering the highest point within the island/complexes is about 3 meters, the 2-meter sea water level rise would place the majority of the island underwater. With the increasing rate of global warming, future generations would suffer the consequences of losing biodiversity on these islands. Based on this study’s findings, we call for the development of more precise, timely prediction of sea level rise impact, as well as long-term conservation strategies specifically designed to protect and maintain the endangered wildlife species residing on the islands, including Florida Key deer and lower Keys marsh rabbits.