The Prespa–Ohrid ecoregion
The Prespa-Ohrid ecoregion lies at the heart of of the Balkans. Covering parts of Albania, Greece and the Republic of North Macedonia, the lakes are among Europe’s oldest and recognized as one of the most ecologically valuable regions in Europe. This widely recognised transboundary area houses six protected areas, three internationally recognised wetland areas (Ramsar site) and a UNESCO Biosphere Reserve.
Prespa refers to two freshwater lakes—the Great Prespa, is shared by Albania, Greece and the Republic of North Macedonia and the Small Prespa is divided by Greece and Albania.
Together with their surrounding mountains the two Prespa lakes constitute an area distinguished by perhaps the greater diversity of life forms to be found anywhere in Europe.
Some numbers help to illustrate the wealth and the diversity of the area:
- The Prespa basin has a very high level of endemism score with >30 endemic forms of lacustrine organisms, mainly gastropods, diatoms, oligochaeta, leeches, poriferans, tricladids, ostracods.
- With 23 species of freshwater fish, of which 9 are endemic to the Prespa region. Prespa is one of the ten most important wetlands in the Mediterranean and one of the 12 most important wetlands in Europe in terms of fish endemism.
- The Prespa lakes are a wetland of international importance (Ramsar wetland). Over 272 species of birds, including 143 breeding are found in the area.Lake Micro Prespa is the home of the largest breeding population of Dalmatian pelicans (Pelecanus crispus) in the world with 1150-1530 p, (20% of its global population) and an isolated colony, the westernmost in the Palearctic, of Great White Pelicans (Pelecanus onocrotalus, 300-500 p.).
– There is also an important population of pygmy cormorants (Phalacrocoraxpygmaeus), one of the four isolated genetically distinct populations in Europe of Goosander Mergus merganser, relicts of glacial eras, and other important water-bird species, such as the Glossy Ibis and 6 species of herons.
- With 172 species of diurnal butterflies the Prespa catchment basin is one of the 10 most diverse places for Lepidoptera diversity in Europe.
- 62 mammal species, with endangered species of wolves, brown bears and otters all finding refuge within the basin. Prespa also hosts one of the highest bat diversities in Europe
- Exceptional floristic diversity with over 2,200 species of plants.
- Great variety of habitat types: 49 habitat types listed in the EU Habitats Directive (92/43/EEC), including 7 priority terrestrial habitats.
Lake Ohrid is located on the central Balkan with approximately two-third of its surface area belonging to the Republic of North Macedonia and about one-third belonging to Albania. It is an ancient lake that exists continuously after its formation during the Pliocene, and one of the oldest lakes in the world. It is also the deepest lake in the entire Balkan Peninsula, with a maximum depth of 289 m.
Lake Ohrid is renowned as a center of biodiversity for continental aquatic species, especially due to its exceptionally high level of endemism. It is much smaller than lakes such as Baikal, Tanganyika and Victoria but hosts a higher number of endemic species and is possibly the most diverse lake per capita surface area, in the world. Lake Ohrid represents a refuge for numerous freshwater organisms from the Tertiary Period, whose close relatives can be found only as fossil remains; this is the reason the lake is sometimes called a “museum of living fossils”. Among them the freshwater sponge (Ochridospongia rotunda).
The work of PONT during its first years will be focused on the Prespa Lakes and their surrounding environment, which includes Galicica National park on the shore of lake prespa.
The significant biodiversity values of Lake Ohrid, indicatively include:
- Approximately 1,200 native species are known from the lake, including 586 animals.
- 212 known endemic species including 182 animals in a lake with a surface area of 358 km2 and mean water depth of 155 m. Εndemism is high in invertebrates with benthic and semi-benthic taxa being particularly diverse. Indicatively:
- Amphipoda 90%, Infusoria 88%, Rhabdocoela 44%, Tricladida 71%, Isopoda 76%, Gastropoda 78%, Ostracoda 63%.
- Ohrid is one of the 12 most important wetlands in Europe in terms of fish endemism, with the presence of 17 species of freshwater fish, including the famous Ohrid Trout (Salmo letnica) as well as 9-11 local or regional endemics.
- The lakeshore reed beds and wetlands provide critical habitat for hundreds of thousands of wintering water birds, including rare and threatened species such as the dalmatian pelican, ferruginous duck, spotted eagle, and imperial eagle. As such, the Ohrid Lake fulfils the Ramsar criterion of regularly exceeding 20.000 birds, with 20,000 – 40,000 overwintering birds.