Dry grasses and clay are odd places to look for frogs – but biologists are walking Indiana’s grasslands in search of them. For the biologists at Big Oaks National Wildlife Refuge, summer droughts may have dramatically changed the landscape, but that has not stopped their efforts to protect the rare crawfish frog.
Crawfish frogs are large, light-colored frogs with ornate blotches marking their bodies. As their name implies, these frogs rely on burrowing crayfish to create the burrows that they occupy throughout the year. Crawfish frog research and management has been a priority for Big Oaks since 2004, when the initial breeding surveys for the elusive amphibians began.
“Crawfish frogs are an indicator of high quality grasslands and perhaps a surrogate species to inform management for other of grassland species,” said Big Oaks Manager Joe Robb.
Though Big Oaks contains 50,000 acres of varied habitat, crawfish frogs can only be found in temporary wetlands. These seasonal ponds are essential habitat for the frogs to reproduce. Even though many of these ponds were lost due to drought, land managers have developed some man-made wetlands to provide much needed habitat this summer.
Despite the inability to dig new ponds on this past military proving ground, biologists enlarged existing wetlands by damming nearby culverts and ditches, effectively flooding the small pools and creating more extensive wetlands that mimic the natural cycles. “Ideally, we would provide the frogs with wetlands that will reliably hold water through much of the summer even in dry years,” explained Robb.
With landscape-level modifications like this, the prospects for crawfish frogs at Big Oaks are promising. Active management and research strategies like these may serve as a model for other ecological systems across the country as managers adapt to a rapidly changing climate.
To learn more about the crawfish frog visit http://amphibiaweb.org/cgi/amphib_query?where-genus=Rana&where-species=areolata.
Image courtesy Andrew Hoffman/USFWS