Modeling, Estimation, and Adaptive Management of Florida Manatees
The Challenge: Florida manatees are threatened by watercraft-related mortality, the potential loss of warmwater habitat, red tide events, and other anthropogenic factors. The USFWS and the Florida Fish and Wildlife Conservation Commission have regulatory authorities under the Endangered Species Act (ESA), the Marine Mammal Protection Act (MMPA), and state statutes to recover manatees. To support management decision-making, these agencies need quantitative assessments of population status.
The Science: Working with scientists at the USGS Sirenia Project and Florida’s Fish and Wildlife Research Institute, Patuxent scientists have have estimated life-history vital rates of manatees, incorporated those into a stochastic population model, and used that model to evaluate the threats facing manatees. Results from Patuxent’s modeling work have been the foundation of several regulatory documents, including the 2005 incidental take regulations under the MMPA, and the 2007 5-year review under the ESA, and the 2016 proposed rule to reclassify manatees to threatened under the ESA.
The Future: To inform development of the final rulemaking regarding reclassification of manatees to threatened, an updated threats analysis is underway. This new analysis will assess the potential risk posed by recent mortality events, and will consider whether climate change may affect the frequency of cold-related morality.
The Challenge: Florida manatees are threatened by watercraft-related mortality, the potential loss of warmwater habitat, red tide events, and other anthropogenic factors. The USFWS and the Florida Fish and Wildlife Conservation Commission have regulatory authorities under the Endangered Species Act (ESA), the Marine Mammal Protection Act (MMPA), and state statutes to recover manatees. To support management decision-making, these agencies need quantitative assessments of population status.
The Science: Working with scientists at the USGS Sirenia Project and Florida’s Fish and Wildlife Research Institute, Patuxent scientists have have estimated life-history vital rates of manatees, incorporated those into a stochastic population model, and used that model to evaluate the threats facing manatees. Results from Patuxent’s modeling work have been the foundation of several regulatory documents, including the 2005 incidental take regulations under the MMPA, and the 2007 5-year review under the ESA, and the 2016 proposed rule to reclassify manatees to threatened under the ESA.
The Future: To inform development of the final rulemaking regarding reclassification of manatees to threatened, an updated threats analysis is underway. This new analysis will assess the potential risk posed by recent mortality events, and will consider whether climate change may affect the frequency of cold-related morality.