Balkan Rivers & Streams | WWF

Balkan Rivers & Streams

Mikra Prespa Lake, Greece.

About the Area

Much of southern Europe escaped glaciation thousands of years ago and hence diversity within water bodies tends to be higher here, than in northern Europe. In addition, the soft limestone that the Balkans are built of, allow water that seeps underground to create subterranean karst channels where many aquatic species live.

The ridge of the Balkan Range is the main watershed between the Black Sea and the Aegean. The deep karst bedrock provides a steady outflow of the underground aquifer feeding those rivers, and the sprawling old forests retain the topsoil moisture. The riverbeds are steep, the rivers are fast and abundant in water.

At many places these rivers jump off high cliffs, forming scenic waterfalls, which the local population calls praskala, or spray gushers. Central Balkan is the scene of some of the highest and most impressive waterfalls in Bulgaria, notably Raiskoto Praskalo (124.5 m.), Vidimskoto Praskalo (80 m.) and Kademliiskoto Praskalo (72 m.).

The Balkans region hosts an extremely diverse and highly endemic (both at a local and regional level) gastropod fauna (snail species), with about 200 known species. For example, the Sava River alone harbours 103 species, of which 54 are endemic. Many endemic fish species and genera are also present in the ecoregion.

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225,000 sq. km (90,000 sq. miles)

Habitat type:

Small Rivers

Geographic Location:
Southeastern Europe: Albania, Bosnia and Herzegovnia, Bulgaria, Croatia, Greece, Italy, Macedonia, Serbia, Slovenia, Turkey, and Yugoslavia

Conservation Status:

Local Species

Restricted mainly to the Dalmatian karst area of Bosnia-Herzegovina, the highly endangered Dalmatian barbel gudgeon (Aulopyge hügeli) inhabits both above-the-ground rivers and subterranean karst rivers.

Subterranean watercourses in the ecoregion also support populations of the highly endangered and endemic Olm, or blind salamander (Proteus anguinus), as well as many endemic invertebrates.

Endemic trout live in the rivers and lakes of this ecoregion, including Ohrid (Salmo letnica), Marbled (Salmo marmoratus), and Belushka (Acantholingua ohridana) trouts, as well as S. dentex.

The ecoregion is home to a number of other endemic and rare fishes, many of which are vulnerable, endangered, or even critically endangered. Among these species are Greek brook lamprey (Eudontomyzon hellenicus), Leuciscus illyricus, and Phoxinellus ghetaldii.

Featured species

Greek brook lamprey (Eudontomyzon hellenicus)

This fish weighs around 7.4 g and its size is about 15.8 cm. It is endemic to Greece. It is a short-lived, freshwater non-parasitic lamprey that lives in shallow, clear, fairly fast-flowing brooks with gravelly substrate, some rocks and aquatic plants.

Ammocoetes larvae are filter feeders on microorganisms, including green algae. Reproduction takes place in January and May. Its existence is threatened by pollution and water obstruction.

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The aftermath of recent conflicts in this region includes large-scale movements of refugees across the region and pollution and fires originating from bombed industrial sources. Other threats comprise agricultural and industrial waste, untreated sewage effluents, and construction of dams.

The ecoregion also includes a large number of introduced species that are believed to have negatively impacted native species. For example, hybridisation of the rare Marbled trout (Salmo marmoratus) with the introduced Brown trout (S. trutta) has reduced the genetic integrity of the native species.

WWF’s work

Across The Waters (ATW) is one of the best known and highly reputed projects run by WWF MedPO. It was chosen by WWF in 1997 as one of the 20 model projects among its world wide portfolio, and is regarded as one of the global "nodes of excellence" for capacity building.

WWF looks to further expand its programme in the countries of the southern and eastern Mediterranean, and it is conscious that the long-term success of the activities it supports can only be reached through the active participation of the local individuals, groups and organisations and through strategic alliances with other environmental groups of the region.

For the coming years, therefore, it has been decided to concentrate much of the effort on helping build the capacity of grassroots environmental groups, to create a strong, active and skilled NGO movement that can reference itself legitimately to local society and play a key role in the effort to preserve the unique natural and cultural heritage of the Mediterranean.

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