Delineating Conservation Areas for Cohabiting Species: An Example of Vernal Pond Conservation From Fort Stewart in Georgia, United States

Military installations are valuable in global biodiversity conservation as they secure representative ecosystems from land conversion and protect many threatened or endangered species. Selecting suitable areas for biodiversity conservation within military installations is a challenging problem as this must not impede military training activities. The issue gets more complicated when considering multiple cohabiting species in a metacommunity with species dependency. In this paper, we present an example for the conservation of two cohabiting species, Gopher Tortoise (GT) and Gopher Frog (GF), located within the boundaries of a military installation, Fort Stewart, Georgia, United States. The GF depends on both locations of GT habitat (burrows) and ephemeral vernal ponds (for breeding). We develop a model that identifies the cost-efficient areas for the conservation of these two species while taking into account the dependency of GF on GT burrows. The model selects a specified number of conservation areas for the two species, where each GF conservation area covers an adequate number of vernal ponds for the GFs to accommodate their reproduction, and each GT conservation area provides adequate habitat quality to sustain a viable GT population. The model also requires each GF site to be located close to GT sites so that the GFs could find refuge after they leave the water. We use the total distance of selected sites to the main roads in the military installation as a proxy for the conservation cost. We achieve contiguity of each conservation area by selecting sites that are adjacent to a central site of the conservation area to ensure undisrupted travel for both the GFs and the GTs. Using the model, we generated alternative configurations of conservation areas that could be considered by the land managers of Fort Stewart. Our methods are general and can be applied to other reserve site selection and land management problems with cohabiting interrelated species.

Comprehensive health assessment and blood analyte reference intervals of gopher tortoises (Gopherus polyphemus) in southeastern FL, USA

The gopher tortoise (Gopherus polyphemus), a keystone species, is declining throughout its geographic range. Lack of knowledge with respect to the potential infectious diseases present within wild populations creates a dilemma for wildlife biologists, conservationists and public policy makers. The objective of this study was to conduct a health assessment of two previously unstudied gopher tortoise aggregations located at two sites in southeastern FL. Samples were collected from 91 tortoises (48 adults, 35 juveniles, 8 hatchlings) captured at Florida Atlantic University’s Harbor Branch Oceanographic Institute, in Fort Pierce, FL, USA in 2019, and Loggerhead Park in Juno Beach, FL, USA, during 2018–2019. Samples of blood, nasal swabs and oral/cloacal swabs were analyzed for hematology, plasma protein electrophoretic profiles and infectious disease testing including Mycoplasma spp. serology and polymerase chain reaction (PCR) assays for Ranavirus, Herpesvirus and Anaplasma spp. Hematological and plasma protein electrophoresis reference intervals are presented for adult and juvenile tortoises from both sites combined. Clinical signs consistent with upper respiratory tract disease (URTD) were observed in 18/91 (20%) tortoises, and antibodies to Mycoplasma agassizii were detected in 33/77 (42.9%) tortoises. Adult tortoises were significantly more likely than juveniles to have URTD clinical signs, and statistically significant, positive relationships were observed between the presence of antibodies to Mycoplasma spp. and carapace length, packed cell volume and plasma globulin concentrations. Anaplasma spp. inclusions were observed in 8/82 (10%) tortoises, but PCR detected Anaplasma sp. in 21/83 (25%) tortoises. Herpesvirus and Ranavirus were not detected in any blood or swab samples. This work contributes important baseline information on the health of gopher tortoises toward the southern end of the species’ range.