FWRI Biologists Work to Restore Flatwoods Salamander Populations in Apalachicola National Forest
Subsisting primarily on a diet of earthworms and spiders, the silvery-gray reticulated flatwoods salamander (Ambystoma bishopi) and the frosted flatwoods salamander (A. cingulatum) inhabit the pine flatwoods-wiregrass ecosystems of the panhandle of our state. Both species of salamanders are long and slender, with a maximum length of about 5.2 inches (13 centimeters).
The frosted flatwoods salamander and the reticulated flatwoods salamander depend on isolated herbaceous ephemeral ponds situated within longleaf pine savannas and mesic flatwoods to complete their life cycles. Adults migrate from their upland retreats to breeding sites on rainy nights from October through December. Long thought to be a single species, the flatwoods salamander was listed as federally threatened in 1999. Subsequent genetic analyses revealed that the flatwoods salamander was actually two evolutionary separate but ecologically similar lineages. In 2009, the US Fish and Wildlife Service amended its listing of the flatwoods salamander, listing frosted flatwoods salamander as a Threatened species, and the reticulated flatwoods salamander as an Endangered species. Most known populations of flatwoods salamanders have been lost to the destruction of the longleaf pine ecosystem, which has largely been converted to development, commercial pine plantations, or agricultural uses. Populations that remain on public conservation lands continue to decline and disappear. Flatwoods salamander breeding habitats were historically maintained by early summer lightning-ignited wildfires that burned through shallow wetlands when they were dry. Modern prescribed fire practices favor burning under unnaturally cool and wet conditions of winter and spring, causing fire to be excluded from inundated wetlands. The result is that most breeding sites have become thickly encroached with woody trees and shrubs, eliminating the plant communities that the salamanders require for nesting and larval survival.
Our Uplands Habitat biologists are currently in the Apalachicola National Forest sampling plants in ephemeral ponds that have undergone restoration to make them suitable for flatwoods salamander breeding. FWRI researchers are working to quantify vegetation characteristics—such as plant species composition, abundance, and distribution—that have been qualitatively described for flatwoods salamander nesting habitat. For example, pipeworts (Eriocaulon spp.) and switchgrasses (Dichanthelium spp.) are important plants sought out by the flatwoods salamander because females lay eggs on the moist soil beneath their leaves.
Over the last two winters, FWC biologists in the Reptile and Amphibian Research lab have worked long hours headstarting larval frosted flatwoods salamanders in the Apalachicola National Forest. The aim of headstarting is to boost salamander numbers in critical populations until their breeding ponds can be restored to suitability. Staff scientists collect eggs from dry breeding ponds in December and bring them in to the lab. Once the embryos develop sufficiently, the eggs are hatched into large water-filled “cattle tank” mesocosms. Because mesocosms are food-rich and predator-free environments, larval survival rates can be much higher than in the wild. In April and May, larval salamanders are captured from the mesocosms as they lose their gills and transform to air-breathing metamorphs. They are marked with coded color tags or microchips, and released them back into their ponds of origin. Breeding ponds are monitored to determine if headstarted salamanders successfully return to breed in subsequent years.
View our Flickr album documenting the efforts to boost the population of this rapidly declining salamander species.
Warm congratulations to FWRI biologist, Pierson Hill, for receiving the Southeast Partners in Amphibian and Reptile Conservation (SEPARC) 2018 Conservation Hero Award! This award is given in recognition for making significant contributions to the conservation of amphibians and reptiles in the southeast region, and successfully achieving on-the-ground conservation for herpetofauna by preventing loss of species or their habitats. Pierson is working on several projects focused on recovering populations of the critically imperiled frosted flatwoods salamander.
Over the past two winters, Pierson has led a team that collected and hatched salamander eggs that would have otherwise perished due to unusually dry conditions. The team has rescued over 2000 eggs, donated more than 400 for captive breeding efforts, and released 1300 metamorph salamanders back into the wild. His efforts have provided a critical boost to rapidly declining populations and made headway in the methodology of headstarting this beautiful and fragile species.
