Anthropogenic barriers to longitudinal river connectivity in Greece: A review

Abstract

An inventory of anthropogenic barriers to longitudinal river connectivity in Greece is presented based on an extensive literature review. We mapped Greece's 275 major dams and developed an ongoing inventory of 661 other barriers compiled from various sources; we further summarized future dam barriers as published in Greece's river basin area management plans. Environmental professionals and engineers were also interviewed to investigate perceptions and preferences concerning longitudinal river connectivity. Fish were given priority as reference organisms in questionnaire responses, the reviewed literature and relevant legislation, but other biodiversity elements were rarely addressed. Dams prevail as the most prominent perceived barrier pressures while most respondents seem to recognize problems with other barrier types as well. However, mention of small barrier infrastructure in the literature or legislation is very scarce and there is no systematic inventory of in-stream infrastructure barriers, fish passes or other barrier mitigation or restoration interventions. Recommendations for particular unmet needs and opportunities for restoration of a variety of barrier types are addressed. It is crucial that attention for preservation and restoration measures involving lotic waters connectivity issues be introduced in the country's EU-inspired water body management and within protected areas in particular.