Is there Hope for the Hoosier Frog? An Update on the Status of Crawfish Frogs
(Lithobates Areolatus) in Indiana, with Recommendations for their Conservation
Authors
Nathan J. Engbrecht
Indiana University School of Medicine–TH
Michael J. Lannoo
Indiana University School of Medicine–TH
Perry J. Williams
Big Oaks National Wildlife Refuge
Joseph R. Robb
Big Oaks National Wildlife Refuge
Todd A. Gerardot
Big Oaks National Wildlife Refuge
Crawfish Frogs (Lithobates areolatus) are a State Endangered species that have
experienced declines through much of their range in Indiana. We conducted surveys at nine
historical sites and detected Crawfish Frogs at only one of them. Data suggest this
species has been extirpated from Benton, Fountain, and Vermillion counties in the north,
Vanderburgh and Warrick counties in the south, and Morgan and Monroe counties in the east.
Robust populations of Crawfish Frogs persist in two areas, at Hillenbrand Fish and
Wildlife Area-West in the southwest, and at Big Oaks National Wildlife Refuge in the
southeast. One cluster of populations remains in Spencer County, in the south. Our data
suggest that there are fewer than 1,000 adult Crawfish Frogs in Indiana: Big Oaks supports
about 300 animals, Hillenbrand supports about 200 animals, and remaining animals are
scattered among populations that are generally small and located on private lands in
southwestern Indiana. Despite these pessimistic data, Crawfish Frogs are resilient and
will establish populations at new sites when habitat becomes available and animals are
close enough to colonize. If Crawfish Frogs are to persist in Indiana, they must become a
component of the management plans on both public and private lands. When this occurs, not
only could the precipitous decline of Crawfish Frogs in this state be halted, but
Indiana’s public grasslands are extensive enough that intervention could lead to the
eventual downlisting of the species.