Compensating the impact of large reservoirs in amphibian communities: a case study. Chapter 1

Hydropower, generated mainly from hydroelectric dams, is a renewable energy that provides electricity and helps in reducing carbon emissions. In the Mediterranean region the construction of dams is also considered fundamental for maintaining water supplies during summer, namely for irrigation and domestic consumption. The construction of dams implies the conversion of small temporary streams and ponds into permanent reservoirs. The massive alteration in the hydrologic cycles and associated physical and chemical processes creates new conditions that promote invasive species occurrence and are considered detrimental to the reproduction of most amphibian species. Additionally, the flooding of certain areas affect many important habitats used by adult amphibians and may impose barrier effects to their movement and dispersion. Using a case study in Portugal, the Baixo Sabor Dam, we pretend to outline the implemented steps to compensate impacts on the amphibian communities, namely to the creation of small temporary ponds. The preliminary monitoring results are also analysed and discussed.