Stephanie Bishir uses radio telemetry to track Northern crawfish frogs. - Photo Credit: Ben Walker/USFWS

The interns at Big Oaks National Wildlife Refuge have been continuing research on the Northern Crawfish Frog (Rana Lithobates; Areolata circulosa). One continued project involves the use of radio telemetry to track the movements of the frogs. For this study, crawfish frogs were collected and outfitted with a radio transmitter belt that enables their location to be detected. The purpose of this study is to monitor the effects of habitat management activities used to manage grasslands, including aerial herbicide and prescribed burns, on the habitat usage of the frogs.

Another study underway at the refuge involves the captive rearing of crawfish frog tadpoles. For this project, Crawfish frog tadpoles were collected and raised in reptariums under different vegetation treatments. These treatments included a control, native broomsedge, invasive fescue, both in 250 gram and 500 gram amounts and cattail in 250 gram. The purpose of this study was to observe the effects of the different vegetation treatments on the survival and development rate and the mass and length of the metamorphs.

A third study involving the crawfish frog aimed to observe any interspecific, intraspecific and predation interactions. For this project, crawfish frog tadpoles, Southern leopard frog tadpoles and marbled salamander larvae were collected and raised in reptariums under different treatments. These treatments included a control with only crawfish frog tadpoles, crawfish frog tadpoles raised with Southern leopard frog tadpoles, crawfish frog tadpoles with both high and low densities of marbled salamanders, crawfish frog tadpoles with Southern leopard frog tadpoles and both high and low densities of marbled salamanders. The purpose of this study was to observe the effects of competition with the Southern leopard frog and predation by the marbled salamander on the survival and development rate and the mass and length of the Crawfish frog metamorphs.

By Stephanie Bishir