HATCH, K.A.; TRACY, C.R.; Brigham Young University; University of Nevada, Reno: Winterkill of Rana luteiventris in a riparian habitat

Little research has been done on the biology of hibernating frogs in their natural habitat. Columbia spotted frogs (Rana luteiventris) are primarily aquatic and anecdotal evidence suggested that they dig into soft banks of streams or pools to hibernate. We implanted transmitters into 13 spotted frogs in the Toiyabe Mountains of Nevada to obtain quantitative data on their natural history and biology of hibernation. We monitored their movements approximately once weekly between October 2000 and March 2001. The frogs overwintered in a variety of habitats. Two of the 13 frogs overwintered in a limited area with at least 40 other frogs. Of the 42 frogs we removed from this site in the spring, 37 were found dead and only 5 survived. Our preliminary evidence suggests these frogs died of anoxia, even though they overwintered in a stream with flowing water.