Abnormal Frogs Less Common Than Feared (IMAGE) University of California - Davis Caption A national survey of wildlife refuges found that the rate of physical abnormalities in frogs and toads was about 2 percent, although there were local "hotspots." The findings suggest that were these abnormalities occur, the causes are local. Pictured: A healthy bull frog. Credit Bill Buchanan, USFWS Usage Restrictions May be reproduced or shared with attribution (Creative Commons 2.0 license). License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.