SCCF Wildlife & Habitat Management Director Chris Lechowicz and Wildlife Technician Nadine Cobb attended Florida SouthWestern State College’s Herpeton: The Florida Herpetology Conference at the Naples Botanical Garden from Oct. 31 to Nov. 2.

The team staffed an SCCF table with educational literature and giveaways highlighting our programs and volunteer opportunities, and Lechowicz gave a lecture on the “History, Current Status, and Future Sustainability of Amphibians (Anurans) on Sanibel Island, FL after Sequential Storm Surge Events.”

The talk focused on the frog and toad species that inhabit Sanibel, and how these species were affected by saltwater intrusion from the storm surges of Hurricanes Ian, Helene, and Milton based on data from 2017 – 2025.

“The frog data comes from our teams frog call surveys that occur monthly from June-September each year at 20 sites,” Lechowicz said. “Our salinity data comes from 25 sites that we sample, representing ephemeral both (temporary) and permanent waterbodies.”

Sanibel’s nine anuran (frog and toad) species all experienced some change post-Hurricane Ian in 2022 due to habitat loss from saltwater intrusion. This is because frogs are osmotically sensitive, and most species cannot tolerate salinities over 3 practical salinity units (PSU).

“The underwhelming rainy season of 2023 resulted in mostly lower call intensity in most species,” Lechowicz said. “However, the highly active rainy season of 2024 showed a sharp spike in call intensity in frog species that breed in ephemeral wetlands — including eastern narrow-mouthed toads (Gastrophryne carolinensis), southern toads (Anaxyrus terrestris), and Cuban treefrogs (Osteopilus septentrionalis) — since these areas had salinities of 5 PSU or lower.”

Two more storm surges occurred in fall 2024 after frog call surveys ended, which caused high salinities again. 2025 was another highly active rainy season that had the same effect as 2024, with ephemeral frogs having a decent year.

The pig frog (Lithobates grylio), a species that inhabits permanent waterbodies, showed major losses island-wide since Hurricane Ian, because permanent waterbodies held high salinities for several years.

Southern leopard frogs (Lithobates sphenocephalus), which often breed in permanent waterbodies, were not heard most years due to frog call surveys from June through September occurring outside their winter breeding season. However, they have been seen crossing roads on rainy nights over the summer and are known to have an above average salt tolerance.

Cane toads (Rhinella marina), which will breed in both ephemeral and permanent waterbodies, are showing increasing call intensity each year from 2023-2025 and are quickly reoccupying the island.

“Amphibians are important environmental indicators because they show immediate effects from changes in habitat from natural and man-made disturbances,” Lechowicz said.