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SCCF Recognized for Filling Gaps at Annual Turtle Symposium
SCCF Wildlife Biologist Mike Mills and Wildlife & Habitat Management Director Chris Lechowicz attended the 22nd Annual Symposium on the Conservation and Biology of Tortoises and Freshwater Turtles in Tucson, Arizona the last week of July.
With more than 260 attendees, it is the largest scientific meeting concerning non-marine turtles in the world. Representatives from 26 countries were in attendance to present their conservation work and research on the most at-risk-of-extinction vertebrate group currently.
There are currently 365 species of turtles recognized today and only seven of them are marine or sea turtles.
Mills gave a talk titled, Hurricane Effects on a Long-Term Monitored Southwest Florida Barrier Island Gopher Tortoise (Gopherus polyphemus) Population. His presentation highlighted the effects of the storm surge from Hurricane Ian on this burrowing tortoise on a barrier island.
“SCCF’s data set that exceeds 20 years at two sites and 17 years at three other sites have had gradual increases and/or declines over that span,” said Mills.
The aftermath of Ian showed drastic losses of active burrows at all sites immediately after the hurricane. One site was 100% loss.
“However, subsequent years surveys in 2023 and 2024 show numbers increasing again,” he said. “But it will likely take years to reach pre-hurricane levels.”
Lechowicz attended the International Union for Conservation of Nature (IUCN) Tortoise and Freshwater Specialists Group meeting to add comments to the species that need to be reassessed.
Lechowicz added comments to the gopher tortoise assessment discussion and supported the decision to uplist them from Vulnerable to Endangered or possibly Critically Endangered after looking at the latest models and predictions.
Over half of the gopher tortoises in the state have been relocated due to development and the half-century outlook on their population is a sliver of current numbers, he noted.
“Conferences and symposiums are essential for showcasing our work to our colleagues. Not only do we make new contacts and share ideas with other researchers, but this leads to collaborations on similar projects,” said Lechowicz. “We were thanked in a couple of lectures for providing data and guidance to other entities working on chicken turtles (Deirochelys) and mud turtles (Kinosternon).”
“Thanks to the support of our community and donors, SCCF’s barrier island wildlife research is gaining a reputation for filling in many gaps of knowledge on both rare and poorly known species,” he added.
Abstract of SCCF study:
Hurricane Effects on a Long-Term Monitored Southwest Florida Barrier Island
Gopher Tortoise (Gopherus polyphemus) Population
MIKE MILLS, CHRIS LECHOWICZ, AND NADINE COBB
Sanibel-Captiva Conservation Foundation, 3399 Sanibel Captiva Road, Sanibel, Florida
[mmills@sccf.org]
The Gopher Tortoise (Gopherus polyphemus) is threatened throughout its entire southeastern United States range due to the loss, fragmentation, and reduced quality of habitat. They face additional threats on islands where there is limited space and resources, as well as infrequent gene flow into the population compared to their mainland counterparts. On a southwest Florida barrier island, Gopher Tortoise burrows were surveyed annually on two different preserves, beginning in the year 2000, and on three additional preserves in the year 2007 to current. Burrows are classified as active, inactive, or abandoned to determine the estimated tortoises per hectare. From the year 2007-2021, all preserves maintained a relatively stable active burrow count. In September 2022, Hurricane Ian caused up to 12 feet of storm surge on the island, flooding burrows and drastically altering Gopher Tortoise habitat. The 2022 survey, following the hurricane, found most active burrows were lost within four preserves, as well as total loss on one preserve. Although these preserve populations have suffered a significant loss of active burrows, the aftermath of the hurricane has accelerated our upland management efforts due to fire hazard, fire line loss and hurricane debris. This provided the opportunity to clear out hardwood hammocks and replant forage plants to increase open-canopy habitats preferred by Gopher Tortoise. Many of these tortoises were displaced on the island from the high water and providing optimal habitat should encourage recruitment back to these areas.