A unique system of wetlands on the eastern Black Sea shore in Georgia

Georgia in the Caucasus is situated on the nexus of Asia and Europe and harbors one of the World’s biodiversity hotspots (Meyers 2000; Cincotta et al. 2000).

Land of the Golden Fleece – Central Kolkheti Wetlands with a splendid view on Imnati bog and the Atchara-Imereti  mountain range visible in the background in winter (photo: Izolda Matchutadze)

When Jason and the Argonauts hit the eastern Black Sea shore – now western Georgia – on their quest to find the Golden Fleece, they must have encountered a land with great promise. The subtropical central or sub-Mediterranean lowland region of Kolkheti along the east coast of the Black Sea is particularly well-endowed with different wetland types, and these in turn are part of an important network of wetlands around the Black Sea (Wilson & Moser 1994; Marushevsky 2003). These wetlands are fed by frequent and often heavy rains (on average 2200 mm annual rainfall) and by a multitude of rivers and underground streams (seepage) from the Atchara-Imereti and Greater Caucasus ranges. This constant water supply made it very difficult to drain wetlands in the region during the Soviet Era. Even today the drainage through many ditches and channels continues, although in many places stalled due to lack of maintenance.

Sea daffodil Pancratium maritimum
is a typical plant species of the threatened dune system

The system of wetlands in Kolkheti lowland from the southern border of the Republic of Abkhazia, extending to the Kakhaberi plain on the Georgian-Turkish border in the south, is comprised of river delta’s (including the major Rioni and Chorokhi rivers), lakes, (fish)ponds and extensive wet meadows, fen marshes, mires and unique percolation bogs (Ispani II and Imnati). Some of the Alder-forested marshes are reminiscent of wetlands in northwestern Europe, like the Weerribben-Wieden in the Netherlands.

The vegetation across the region is divers, including huge Sphagnum-dominated bogs to alder brooks with extensive canals and lakes, also fringed by broad reed lands. The wetlands also connect with other special ecosystems like the Euxine-Colchic broadleaf forests, coastal dunes and areas of steppe from the east, in places forming unique ecotones.

Hans Joosten of Greifswald University.

The ecohydrologically unique Ispani II mire is one of the best studied of the percolation bog systems in the region, with research initiated on the basis of sheer coincidence during a Wetlands International meeting in Moscow in 1998 by Erwin van Maanen of EcoNatura and a research team from the University of Greifswald (Germany) led by Prof. dr. Hans Joosten. This research, as well as a conservation programme and including the training of Georgian ecologists and involvement with the International Mire Conservation Group (IMCG), continues today (Haberl et al. 2006; Krebs et al. 2009).

The central part of the Kolkheti wetlands has been protected as national park under de Ramsar Convention since 1999. Their protection is greatly facilitated and promoted by the NGO Tchaobi, led by botanist Izolda Matchutadze and supported by the World Bank sponsored IZCM project.

The biodiversity of the region is poorly characterised and in need of a systematic and phenological survey. Birdlife is the best known and documented (Gavashelishvili et  al. 2006).

Entomofauna of the Colchis region is poorly known. Here a female White-tailed skimmer Orthetrum albistylum

For example, the fish fauna is of great importance ecologically and economically. For instance, at least three of the five Black Sea sturgeon species and the endemic Black Sea Salmon (Salmo labrax) are believed to still spawn in the Tikori and Enguri Rivers, but continued poaching are bringing them to extinction. Surveys of sturgeon have unfortunately stopped with the passing away of Dr. Zurab Zarqua, a Georgian sturgeon specialist.

Three species of sturgeon from the Black Sea. Top-down: Beluga sturgeon (Huso huso), Bastard sturgeon (Acipenser nudiventris), and Diamond sturgeon (Acipenser guldenstaedti colchicus).

Of the wetland mammals, the otter is of conservation concern and the occurrence of another Mustelid – the European mink – is not unthinkable. The Golden jackal is the most common of the larger mammalian predators. The wetlands hold important populations of breeding birds including several species of herons, grebes, birds of prey, waterfowl, rails & crakes and passerines. Sadly – once common – pelicans now only sporadically occur and only two breeding pairs of White-tailed eagle are known to exist today. The wetlands also present vital wintering and storm refuge sites for many birds. Moreover, huge numbers of migratory birds pass and rest in the region during the autumn and spring migration, including around a million raptors in the fall.

The Nabada marshes with their peat cut channels are very reminiscent of the Dutch Weerribben-Wieden (photo: Izolda Matchutadze).

Perhaps now only a small detail, the wetlands are also the original breeding grounds of the now very rare and endemic Common pheasant Phasianus colchicus, commonly introduced as a game species elsewhere around the world.

Illustration of the Ispani II percolation bog by Izolda Matchutadze

The sub-tropical Euxine-Colchic broadleaf forests extending in parts still from the Adjarian mountains (including Mtirala National Park) to the coast (the Botanic garden in Batumi still holds a fragment right on the sea shore) is also a poorly known forest system. These forests from broadleaved to sub-alpine zones are home to unique and endemic species, including the Caucasian salamander (Mertensiella caucasica).

The herpetofauna of western Georgia is not well known. Here a slow worm Anguis fragilis colchicus encountered in the foothills near Batumi in September 2012.

The mountain forests are strongholds for poorly known populations of mammals, including the brown bear, wolf, lynx, wild cat, pine marten, red deer, and other wild herbivores, and a diverse smaller mammal community.

Pine marten in a lush forest near Keda (photo: Jimsher Mamuchadze)

A system under great threat

However, these important and seemingly underexposed wetlands have been, and still are, greatly impacted by anthropogenic activities. As early as 1907 N.N. Shavrov of the Russian Geographers Society predicted the degradation of Kolkheti Wetlands and threats to important inhabitants like birds. As much as 60% of the original wetland area has since been claimed and cultivated for pastures, agriculture and horticulture, a process continuing today and particularly enhanced by rapid urbanisation along the coast.

The Churia fen marsh was damaged by an oil transfer station and supply railway line in 2005, despite its Ramsar status. The Georgian government was obliged to compensate the wetland loss, but no measures have yet been taken.

The increasing degradation of the remaining wetlands was and is currently forced by severe pollution, eutrophication, peat exploitation, over-exploitation of fauna (poaching), illegal logging, drainage, overgrazing, sand and gravel extractions, normalization of flowing waters, invasive species and feral animals. Major developments are in the pipeline, including the ambitious and controversial building of a new city (Lazika) in the Anaklia marshes, oil storage and transfer facilities, extension of a tourist boulevard into the Chorokhi Delta, and hydroelectric dams in the major rivers.

Boardwalk into the Ispani II mire. The plants in the foreground are an invasive species; Knotweed Polygonum thunbergii from Japan. This has spread since grazing with cattle on the fringe of the reserve was forbidden.

Without wise planning and management Kolkheti Lowlands will definitively turn into a hotchpotch of disturbed and disheveled sites. This will inevitably lead to great landscape and biological diversity losses, making the region unattractive for ecotourism. Nature is a great asset for Georgia, yet little appreciated. Of paramount importance to the economic viability of the region, the Kolkheti wetlands provide vital ecosystem services including carbon sequestration against climate change (and hence sea rise, including the Black Sea), coastal stabilisation, buffering against flooding on the low lying Colhic plain, and food and fibre provision (Goradze 2008).

Panels with information about the ecological values of mires and bogs at the visitor centre for Ispani II, located next to the tourist town of Kobuleti, educate possibly around 6000 visitors each year.

References

Abuladze, A. (1994) Birds of Prey in Georgia in the 20th Century. In: Meyburg, B.-U. and R.D. Chancellor, eds. Raptor conservation today. World Working Group of Birds of Prey. London: Pica Press.

Cincotta, R.P., J. Wisnewski and R. Engelman 2000. Human populations in biodiversity hotspots. Nature 404:990-992.

Gavashelishvili, L., Z. Javakhishvili & G. Darchiashvili 2006. Field guide to the birds of Kolkheti Wetlands. Buneba Print/ Georgian Centre for the Conservation of Wildlife, Tblisi, Georgia.

Goradze, I. 2008. The Black Sea coastal Wetlands Vision: Georgia. Black Sea Regional Initiative for the wise use of Coastal Wetlands. PSOVI, Batumi, Georgia.

Haberl, A., M. Kahrmann, M. Krebs, I. Matchutadze & H. Joosten 2006. The Imnati Mire in the Kolkheti Lowland in Georgia. Peatlands International 1:35-38.

Krebs, M. A. Kaffke, P. de Klerk, I. Machutadze & H. Joosten 2009. A future for Ispani 2 (Kolkheti, Georgia) and adjacent lands. International Mire Conservation Group Newsletter 2: 3-14.

Maanen, E. van, I. Goradze, A. Gavashelishvili & R. Goradze (2001) Trapping and hunting of migratory raptors in western Georgia. Bird Conservation International 11:77-92.

Marushevsky, G. 2003. Directory of Azov-Black Sea coastal wetlands. Wetlands International, Kyiv.

Myers, N, R.A. Mittermeier, C.G. Mittermeier, G.A.B da Fonseca and J. Kent 2000. Biodiversity hotspots for conservation priorities. Nature 403:853-858.

Tarkhnishvili, D.N. & I.A. Serbinov 1993. The ecology of the Caucasian salamander (Mertensiella caucasica) in a local population. Asiatic Herpetological research 5:147-165.

Wilson, A.M. and M.E. Moser 1994. Conservation of Black Sea wetlands. A review and preliminary action plan. IWRB Publication 33, Slimbridge.

 

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