Natural History: The Southern Cricket Frog, Acris gryllus

It had been a particularly rainy morning the day we visited the Caw Caw County Park on the outskirts of Charleston. While it was great weather to find amphibians, the prospect of tracking them down in torrential rain was less than appealing. But lucky for us the clouds parted just as we hit the road to make for a beautiful afternoon of dip netting and trap checking. 

Once hip waders were donned, we set off through the woods littered with pine needs, leaves, and more than a few puddles. After wadding out into thigh deep, murky water and dip netting handfuls of leaves, I decided to take the higher and drier road. It was when I was walking through the pine needles and trees that I saw these little things no bigger than a nickel jumping through the debris. Forgetting that I was holding a net I used my hands like I would any other time to catch little frogs. Once narrowing it down to a cricket frog-part of the Hylidae family-based on the small size (they roughly range between 1.6-3.2 cm), the pointed head, slim waist, long hind limbs that make them superb jumpers, slightly warty or bumpy skin, and the 2 green lines running from behind the eyes and meeting at the neck to form 1 line running down the back, forming a dark triangle between the eyes. Trying to identify the species however was a little misleading. The tricky part came when distinguishing it between a southern cricket frog and the northern cricket frog, Acris crepitans. In our field guide the coloration of the northern cricket frog matched the one I caught consisting of dark brown with the green striping compared to the depiction of the southern cricket frog that was a much lighter tan color and void of brighter pigmentation. However, the coloration can vary so one must examine the amount of webbing on the hind feet to establish the species. The southern cricket frog has less webbing compared to the northern. The 4^th toe (longest) has the last 3 joints free as well compared to the northern, which only has about 1.5-2 joints free. After establishing that there was little webbing, we knew it was a southern cricket frog. We were unable to identify the gender, however it is noted that females generally are larger by a few millimeters… good luck. Males do have a single vocal pouch.

These frogs vocalize by producing what sounds like a metallic noise similar to a gick, gick, gick clicking. Hence the name cricket for its sound resembling the insect's chirp. Males in the hopes of finding a female to mate with produce these advertisement calls and the breeding season generally occurs from February to October; the duration is heavily dependent on the amount of rain. These frogs have a complex life cycle that requires a large clutch of eggs (~150) deposited in freshwater, hatch into larvae, and tadpoles metamorphose into adults.

Southern cricket frogs were rather prolific through the area and while I only caught one, there were many more hopping around. There were about 3 more caught that day and we examined the toes and webbing every time. These cricket frogs are commonly found in the lowlands around bogs, ponds, and swamps. They are not climbers but excellent jumpers. These frogs prefer shallow waters with lots of vegetation for cover and will take advantage of sunny days. Considering the ecology of the wetland habitat at Caw Caw with cypress swamps, marshland, reclaimed rice patties, and damp wooded areas, I expect there to be a large population of these small anurans. Their range covers Mississippi through the coastal areas up to North Carolina, excluding Florida where the Florida cricket frog presides.

Peterson Field Guides: Reptiles and Amphibians Eastern/Central North America; pp 529-531.

http://www.nwf.org/Wildlife/Wildlife-Library/Amphibians-Reptiles-and-Fish/Southern-Cricket-Frog.aspx