MEPS 462:287-301 (2012)  -  doi:10.3354/meps09732

Passive thermal refugia provided warm water for Florida manatees during the severe winter of 2009−2010

B. M. Stith1,*, D. H. Slone2, M. de Wit3, H. H. Edwards3, C. A. Langtimm2, E. D. Swain4, L. E. Soderqvist5, J. P. Reid2

1Jacobs Technology, Inc./US Geological Survey, Southeast Ecological Science Center, Gainesville, Florida 32605, USA
2US Geological Survey, Southeast Ecological Science Center, Gainesville, Florida 32605, USA
3Florida Fish and Wildlife Conservation Commission (FWC), Fish and Wildlife Research Institute (FWRI), St. Petersburg, Florida 33701, USA
4US Geological Survey, Florida Water Science Center, Ft. Lauderdale, Florida 33135, USA
5US Geological Survey, Florida Water Science Center, Ft. Myers, Florida 33901, USA

ABSTRACT: Haloclines induced by freshwater inflow over tidal water have been identified as an important mechanism for maintaining warm water in passive thermal refugia (PTR) used by Florida manatees Trichechus manatus latirostris during winter in extreme southwestern Florida. Record-setting cold during winter 2009−2010 resulted in an unprecedented number of manatee deaths, adding to concerns that PTR may provide inadequate thermal protection during severe cold periods. Hydrological data from 2009"