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The management actions in the wildlife ponds on Coldwater National Wildlife Refuge create a highly variable and dynamic environment for amphibians and reptiles. Some ponds contain water for long periods of time and others briefly. Managed ponds have different wetdry cycles than unmanaged ponds . In addition, control of willow invasion by chemical and mechanical means represents levels of perturbation that may affect amphibians. This report summarizes three years of field investigations on these animals in this dynamic environment. Total amphibian species richness for the refuge was 12. Species richness among ponds ranged from 2 to 10; modal number of species per pond was 4. Number of frog species ranged from 2 to 10 per pond. Two species of salamanders were encountered: Siren intermedia and Notophthalmus viridescens. Average number of species in treatment ponds 4.33 was nearly identical to the average number in notreatment ponds 4.25 and not significantly different. Number of tadpole captures per trap night in minnow traps a measure of relative abundance in treated ponds 0.722 was slightly higher than captures per trap night in notreatment ponds 0.594 but the difference was not significant. Analysis of body size relationships in Leopard Frog samples obtained during the same sampling period showed that disk and herbicide treatments do not directly affect body sizes and development of this species. The variable responses to changing water levels by reproductive adult amphibians create the complex interplay of management treatments mostly drawdown schedules with water levels, natural water loss from evaporation, frog responses to water dynamics, species larval developmental periods, and food availability from pond flora. The primary conclusion is that frog populations apparently have not been adversely or directly affected by management treatments of disking or herbicide applications.