EVALUATING IMPACTS TO FLORIDA PANTHER HABITAT: HOW POROUS IS THE UMBRELLA?

Abstract

The endangered Florida panther (Puma concolor coryi) shares its shrinking habitat with agriculture, surface mining, and rapid urban growth. Although panthers have extensive home ranges and use diverse land covers, methods that dominate panther habitat evaluation for Endangered Species Act (ESA) consultations and regional land use planning consider only forested day-use elements within the landscape mosaic. Maehr and Deason (2002) present a Panther Habitat Evaluation Model (PHEM) that, in addition to excluding nonforested habitat, reduces the assessed value of forest patches based on criteria for patch size, forest type, proximity to a “core” area, and connectivity to other patches. An examination of the foundations of PHEM is therefore warranted. Building on earlier work that included an evaluation of panther habitat selection studies (Comiskey et al. 2002), we examine PHEM in light of data quality criteria and the panther's known life history requirements. We conclude that the precepts and rules of the PHEM methodology are based on unwarranted assumptions, nonstandard methods of analysis, and exclusion of relevant data, leading to an undue emphasis on day-use land cover and forest patches larger than 500 ha. Large areas of southern Florida that have abundant prey and are intensively used by panthers would score low in PHEM habitat assessments because they lack large forest patches. We discuss the conservation implications of applying a methodology that discounts substantial portions of occupied panther habitat as unsuitable, and describe an alternative approach to habitat definition and evaluation that is both consistent with panther habitat requirements and applicable to conservation decision-making. Conserving sufficient habitat for recovery of the panther extends an umbrella of protection to the many species that dwell within its range.