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	A multi agency project funded by US EPA's STAR Program

Sampling Frogs and Other Amphibians

Amphibian larvae are sampled in two ways: by trapping in minnow traps and using a timed search. Minnow traps are essentially funnels that direct small swimming animals into a mesh cage (mesh openings are 3 mm). Traps are placed 10 meters apart in wetlands and are checked every 24 hours. All amphibian species found in the traps are identified, counted, and released.

During the timed search, researchers are looking for all life stages of amphibians (eggs, tadpoles and adults). The researchers systematically search the wetland site for 30 minutes and record the species, number, and life stage of all amphibians seen, heard, or captured using a small net.

Adult frogs are most easily sampled with calling surveys conducted during the breeding season. Researchers stand at a selected point and record all frog species they hear during a 3 minute period at dusk. The hard part is estimating how many frogs are calling!