Status, Distribution, and Management of Gopher Tortoises in Highly Urbanized Southeastern Florida

Gopherus polyphemus (Gopher Tortoise) populations are declining throughout their range. Western Gopher Tortoise populations have received strict legal protections and substantial research, yet similarly declining populations in southeastern Florida have received far less conservation and research attention. Herein we conduct the first review of Gopher Tortoise populations in extreme southeastern Florida (Palm Beach, Broward, and Miami-Dade counties), an area heavily impacted by anthropogenic stressors such as urbanization, habitat fragmentation, and climate change. Our objectives were to document the existing distribution of Gopher Tortoises in southeastern Florida, to assess age structure, to evaluate habitat associations, and to review habitat-management activities at focal sites in this region. Among the authors, we knew of 8 focal Gopher Tortoise sites in South Florida. We supplemented this site knowledge with occurrence records from community-science databases, and we found 30 additional ground-verified, tortoise localities across the study area. We surveyed burrows at the 8 focal sites and measured burrow width at 1283 burrows across 6 of these focal sites to estimate age structure. Tortoise populations were generally in small, protected areas (average of 43 ha, median of 18 ha). Of our 6 sites with burrow-size data, all showed presence of adult and juvenile burrows consistent with reproduction, but 4 showed bimodal size structures suggesting low or intermittent survival of subadult tortoises. This data synthesis should be foundational for the development of evidence-based conservation planning for populations of the species confronted by impacts from urbanization and climate change. We highlight conservation and research needs for tortoise populations in extreme southeastern Florida.