The following papers relate to Lake Ohrid, its limnology, its biodiversity and its massive resources for the study of the environment, climate and evolution.
Ramsar Information Sheet: Lake Ohrid together with Studenchishte Marsh was finally designated as a Wetland of International Importance under every criteria of the Ramsar Convention in 2021, despite several years of obstruction by the Macedonian Ramsar Committee, including its head, Branko Micevski, and the Ministry of Environment and Physical Planning. Ohrid SOS wrote 90% of the text for the designation sheet. Nonetheless, when the final version was sent by the state party, important species appeared not to have been included. Perhaps even more seriously, the final boundaries of the Ramsar Site decided by Macedonian authorities cut out the entire area of the former Struga Marshes.
Pollen-based temperature and precipitation changes in the Ohrid Basin (western Balkans) between 160 and 70 ka (Sinopoli et al, Climate of the Past) focuses on the penultimate glacial and last interglacial by analyzing evidence in sediment cores taken from the center of Lake Ohrid. Results resemble climate patterns from North Europe and show cold, dry conditions giving way to wetness and warmth with temperatures elevated 2 degrees above present for the interglacial.
Miocene siliceous microfossils from the open cast coal mine Gračanica (Bugojno paleolake, Bosnia and Herzegovina) and their significance: a preliminary report (Pisera et al, Palaeobiodiversity and Palaeoenvironments) uncovers more clues to the history of Ohrid sponge, suggesting that the genus Ochridaspongia evolved earlier than previously thought and providing evidence that Lake Ohrid acts as an evolutionary reservoir for its endemic sponges.
Potential Threats to Macroinvertebrate Fauna in Lake Ohrid Watershed: Pollution and Alien Species (Trajanovski et al, Acta Zoologica Bulgarica) finds no non-natives from samples that took in 79 taxa but discovers that the ecological status of the lake is much lower than that of tributaries, perhaps due to a “general decrease in the stability and functionality of the lake ecosystem”.
Recent ecological change in ancient lakes (Hampton et al, Limnology and Oceanography) makes frequent reference to Lake Ohrid in an explanation of both why long-lived inland waters have unusual importance to humankind and how this is threatened by a suite of stressors from climate change and microplastics to hydrological alterations and sewage.
The environmental and evolutionary history of Lake Ohrid (FYROM/Albania): interim results from the SCOPSCO deep drilling project (Wagner et al, Biogeosciences) presents early insights from one of the most complete ancient lake drilling cores in the world, addressing questions such as the age of Lake Ohrid and how evolutionary and environmental processes interact.
Zooplankton in ancient and oligotrohic Lake Ohrid in association with environmental variables (Tasevka et al, Croatian Journal of Fisheries: Ribarstvo) reveals the spatial and seasonal patterns of this important species group, which, alongside containing endemic taxa, is a key element of the Lake Ohrid food chain.
Vulnerability of European freshwater catchments to climate change (Markovic et al, Global Change Biology) finds that, of 18,723 catchments across the continent, the sibling lakes of Ohrid and Prespa are the most threatened by rising temperatures.
Liver pathology of female Ohrid trout (Salmo letnica Kar) from the eastern coast of Lake Ohrid: Baseline data suggesting a pollution gradient (Jordanova et al, Turkish Review of Fisheries and Aquatic Sciences) is the second paper to indicate a pollution curtain dividing the north and south of the lake. It hints that diminishing water quality may also be contributing to Ohrid trout to extinction.
The status of an isolated population of Goosander Mergus merganser in the Balkans (Catsadorakis et al, Wildfowl) reports on the small, hidden Ohrid-Prespa population of goosander, which represents the southernmost breeding group in the Western Palearctic region.
Differential resilience of ancient sister lakes Ohrid and Prespa to environmental disturbances during the Late Pleistocene (Jovanovska et al, Biogeosciences) examines how Lake Ohrid has reacted to incidents in the deep past such as glacial cycles, volcanic eruptions, landslides and earthquakes etc. by studying its diatom community through time, discovering no disturbance-related extinction or regime shift.
A freshwater biodiversity hotspot under pressure – assessing threats and identifying conservation needs for ancient Lake Ohrid (Kostoski et al, Biogeosciences) is probably the most complete overview of current threats to the inland water, analyzing everything from climate change to the disturbance of spawning grounds by speed-boats. Recommendations such as in-lake protected areas are also put forward.
Diversity and dynamics of the fungal community in Lake Ohrid (Comic et al, Aquatic Biology) represents the first local study of aquatic fungi, listing 36 species of that were recovered from 5 fieldwork sites. It is the first hydromycological study for Lake Ohrid.
The last glacial-interglacial cycle in Lake Ohrid (Macedonia/Albania): Testing diatom response to climate (Reed et al, Biogeosciences) underlines the importance of Lake Ohrid for understanding environmental and evolutionary responses to climate change.
Biodiversity of ichythyofauna from Lake Prespa, Lake Ohrid and Lake Skadar (Talevski et al, Biotechnology and Biotechnological Equipment) provides the complete breakdown of native, alien, endemic, and shared fish species for the three inter-connected lakes of the Drim Basin.
Ancient Lake Ohrid: Biodiversity and Evolution (Albrecht & Wilke, Hydrobiologia) summarizes the existing knowledge about Lake Ohrid, including a species breakdown, formation and origin, endemism rates, geology and even threats. It is probably the most complete introduction to the lake available.
Eutrophication of ancient Lake Ohrid: global warming amplifies detrimental effects of increased nutrients (Matzinger et al, 2007, Limnology and Oceanography) predicts that warming global temperatures will significantly worsen the effects of nutrients entering Lake Ohrid, resulting in extreme oxygen depletion. The answer is to reduce phosphorous inputs by about 50%. Studenchishte, we need you.
Sensitivity of Ancient Lake Ohrid to Local Anthropogenic Impacts and Global Warming (Matzinger et al, Journal of Great Lakes Research) evaluates how climate change, water abstraction and eutrophication may affect Lake Ohrid, concluding that the latter is the biggest threat due to the knock-on consequences of lost water clarity, particularly to plankton communities, increased water column stability and elevated oxygen consumption.
Lake Ohrid – A Unique Ecosystem Endangered By Eutrophication? (Matzinger, A. via BALWOIS) discovers that human-caused eutrophication is indeed underway at Lake Ohrid with a 4-fold rise in phosphorous inputs over 100 years. Households are the main source, followed by agriculture. The paper focuses on water treatment and agricultural practices as targets for improvement.
Lake Ohrid, Macedonia and Albania management experience and lessons learned brief (Avramoski et al) is a project evaluation that reveals how Lake Ohrid may have unnaturally aged by thousands of years due to eutrophication, which has already resulted in shifts in species’ composition. Advice includes policy and institutional reform.
Lake Ohrid and its Watershed. Our lake. Our Future. A State of the Environment Report (Watzin, 2003) is a frequently cited document giving a thorough background to the ecological and socio-economic parameters that influence Lake Ohrid. Its message on the importance of reeds and wetlands is still being ignored.