FrogWatch monitoring resumes with summer showers
The beginning of the summer rainy season heralds the breeding season for most of Sanibel’s toad (anuran) species, the Sanibel-Captiva Conservation Foundation reported.
During the dry season, they keep moist in some permanent water bodies, such as lakes and rivers, or seek out damp places to avoid desiccation, or drying out, such as burrows, fallen trees, bark piles or by simply burying themselves. The onslaught of regular June and July rains in Southwest Florida invites frogs and toads to emerge and breed in both temporary and permanent water bodies.
To understand the local anuran species, and the health of their populations, the SCCF participates in the national FrogWatch program through the Southwest Florida Amphibian Monitoring Network. SCCF biologists visit 20 sites across the island every third Wednesday of the month — from June through September — after dark to record the species heard, call intensity, temperature, humidity, wind speed, sky condition, traffic noise and other environmental variables.
“Amphibians (frogs, toads and salamanders) are an excellent indicator species for water quality and environmental problems,” Wildlife & Habitat Management Director Chris Lechowicz said. “Because their skin is exceptionally absorbent, they take in water constantly, as well as toxins. A reduction or total loss of a frog species in a wetland can mean some type of environmental contamination, loss of water quality or habitat change has occurred.”
“(While) some frog and toad species are more tolerant than others of contaminants, the loss of a highly sensitive frog species can mean the beginning of an issue in a wetland,” he added.
Male anurans attract breeding females by producing a species-specific call in areas — wetlands — suitable for egg deposition. On a good night, you can hear hundreds of male frogs calling all at once. The nine species of frogs and toads on Sanibel have distinct mating calls, and SCCF volunteer frog monitors have been trained to identify the nuances in each species’ distinctive calls.
The information is added to the extensive Southwest Florida Amphibian Monitoring Network database, which is shared at the national level through FrogWatch and the North American Amphibian Monitoring Program, for an understanding of how amphibian populations are faring across the country.
For questions about frog or toad calls, contact clechowicz@sccf.org.