Lake Ohrid (41°N, 21.7°E) is a 358 km2 large and >280 m deep transboundary lake with approximately two thirds of its surface area belonging to Macedonia and about one third belonging to Albania. With more than 210 endemic species described, the lake is a unique aquatic ecosystem and a hotspot of biodiversity. Though the lake is considered to be the oldest, continuously existing lake in Europe, the age and the origin of Lake Ohrid are not completely unravelled to date. Age estimations concentrate around two to five million years, and both marine and limnic origin are proposed.
Extant sedimentary records recovered between 2005 and 2007 from Lake Ohrid cover the last glacial/interglacial cycle and reveal that Lake Ohrid is a valuable archive of volcanic ash dispersal and climate change in the central northern Mediterranean region. These records, however, are too short to provide information about the age and origin of the lake and to unravel the mechanisms controlling the evolutionary development leading to the extraordinarily high degree of endemism. Concurrent genetic breaks in several invertebrate groups indicate that major geological and/or environmental events must have shaped the evolutionary history of endemic faunal elements in Lake Ohrid. High-resolution hydroacoustic profiles (INNOMAR SES-96 light and INNOMAR SES-2000 compact) taken between 2004 and 2008, and multichannel seismic (Mini-GI-Gun) studies in 2007 and 2008 demonstrate the interplay between sedimentation and active tectonics, but also reveal that well stratified sediments up to 680 m thick exist in the central part of the basin. This impressively proves the potential of Lake Ohrid for an ICDP deep drilling. The principal objectives of the SCOPSCO initiative to be tackled through deep drilling in 2013 are to:
- Obtain more precise information about the age and origin of the lake;
- Unravel the seismotectonic history of the lake area including effects of major earthquakes and associated mass wasting events;
- Obtain a continuous record containing information on volcanic activities and climate changes in the central northern Mediterranean region;
- Better understand the impact of major geological/environmental events on general evolutionary patterns and the extraordinary degree of endemic biodiversity as a matter of global significance.
International collaborators (PI’s) within the framework of this project are: B. Wagner (lead-PI, U. Köln, Germany), T. Wilke (U. Giessen, Germany), S. Krastel (U. Kiel, Germany), K. Reicherter (U. Aachen, Germany), A. Grazhdani (U. Tirana, Albania), G. Kostoski (HBI Ohrid, Macedonia), G. Zanchetta (U. Pisa, Italy).