Freshwater fishes of Greece: Their biodiversity, fisheries and habitats

Abstract

In the present work, we review the current state of knowledge and research trends on freshwater fishes of Greece to assess a) the status of fish populations and their habitats; b) the state and priorities of fisheries science and legislation; c) priority gaps and needs in freshwater fish habitat management; and d) future strategies for freshwater fishes and aquatic resources. Freshwater fish fauna of Greece currently consists of 135 taxa including diadromous and introduced species. The taxonomy of some taxa is unclear. The distribution and origin of freshwater fishes, especially endemics, has been attributed mainly to the geological history of the country. Commercial fishing in inland waters is conducted mainly in 32 natural or artificial water systems. The total annual commercial catch for the 1988–2000 period ranged from 1,950 t in 1988 to 1,810 t in 2000 with a mean annual catch of about 1,500 t. The major part of inland catches comes from lakes, while catches from rivers are of minor importance. Aquaculture contributes greatly to the total production of freshwater fishes. The total annual aquaculture production for the period 1988–2000 ranged from 2,638 t to 3,656 t with a mean annual production of 2,832 t, 1.33 to 2.02 times higher than the traditional inland catches. Due to human activities, Greece has lost 75% of its wetland area since 1900. Today, the pressures upon the surface freshwater resources are moderate with the exception of some systems where human intervention is intense, leading to species extirpations from their type localities. Recently, surface waters have been classified under the auspices of the European Union Water Framework Directive where fishes have an essential role as indicators of the ecological integrity of running waters. Under this concept, there is an increasing emphasis on gathering biological data, to serve a broad-spectrum of environmental objects and plans such as the protection of endangered and threatened species. However, to date effective management and conservation of freshwater fishes and fisheries have not been much considered in the management of freshwaters of Greece. Existing plans for managing aquatic inland resources primarily focus on water usage and do not include specific, enforceable monitoring and management objectives, conservation actions, and control measures for aquatic habitats and fish communities, including endangered and threatened fishes. It is concluded that future efforts need to be directed to severely endangered or nearly extinct species. Furthermore, the creation of GIS-based databases for incorporating all the information on species, habitats and genetic diversity should be addressed under the guiding principle of conserving aquatic biodiversity.