Assessing small hydropower plants impact on Eurasian otter. Case study: the Buzău River, Romania

Abstract

In recent years, in Romania has been registered a substantial increase in the number of small hydropower plants (SHPs) as an alternative of renewable energy source. The construction of small hydropower plants on the rivers of Romania's NATURA 2000 areas is often controversial, being violated national and European legislation. This study aims to assess the otter distribution in the area of a SHP construction project and to find out which is the potential impact of such projects on otter. The standard otter survey methodology proposed by the IUCN Otter Specialist Group was applied for otter evaluation in the area of the SHPs construction and a literature review was used for assesing the impact of the SHPs before construction. The Eurasian otter presence was found in all the survey areas even if the species was absent from the data form of the Natura 2000 Site ROSCI0103 Buzau Everglade, where the study is located. The potential impact of the SHP construction on otter, was not assessed by the assessor in the environmental assessment impact study, for this reason. That's why we review the litterature and use the GIS technology, for understanding and evaluate the potential impact on otter. We found out that this protected top predator of the aquatic ecosystem, the Eurasian otter is potentially affected by the decrease of food resources, destruction of otter holts due to reduced river flow from 21.6 m³/s to less than 5 m³/s and the heavy machinery and workers who work in the riverbed.