Growing concern about the decline of certain amphibian populations and for conservation of amphibians and reptiles has led to renewed awareness of problems from pesticides. Testing amphibians and reptiles as a requirement for chemical registration has been proposed but is difficult because of the phylogenetic diversity of these groups. Information from the literature and research may determine whether amphibians and reptiles are adequately protected by current tests for mammals, birds, and fish. Existing information indicates that amphibians are unpredictably more resistant to certain cholinesterase inhibitors, and more sensitive to two chemicals used in fishery applications than could have been predicted. A single study on one species of lizard suggests that reptiles may be close in sensitivity to mammals and birds. Research on effects of pesticides on amphibians and reptiles should compare responses to currently tested groups and should seek to delineate those taxa and chemicals for which cross-group prediction is not possible. New tests for amphibians and reptiles should rely to the greatest extent possible on existing data bases, and should be designed for maximum economy and minimum harm to test animals. A strategy for developing the needed information is proposed. Good field testing and surveillance of chemicals in use may compensate for failures of predictive evaluations and may ultimately lead to improved tests.
