Creating Successful Vernal Pools: A Literature Review and Advice for Practitioners

Vernal pools provide critical breeding habitat for amphibians adapted to temporary waters, but they seldom receive the same level of protection as permanent wetlands. In response to continued degradation and loss of pools, managers often attempt to mitigate losses through pool creation or restoration. However, mitigation efforts often fail to provide suitable aquatic habitat for vernal pool amphibians. We review the literature on pool creation in northeastern and central North America, highlighting how and why constructed pools often fail to support amphibian-related objectives. We recommend that practitioners consider the complex ecology of pool ecosystems and the historical and current distribution of pools and other wetlands in their local context before designing pool mitigation projects. Using vernal pool creation as a mitigation option should be a last resort (i.e., when elimination of natural pools is unavoidable). Monitoring should be target-specific and conducted for at least 5 years. Topographic, geologic, and other local factors affecting pool hydrology and ecology vary regionally; pool creation remains an imperfect science that will only advance by documenting failures and successes. We recommend an adaptive management approach to vernal pool creation in which the effectiveness of techniques is evaluated and refined based on research.