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Biodiversity of Erusheti National Park
Erusheti National Park
The exceptional biodiversity of Erusheti National Park is primarily determined by its transitional biogeographical location between the humid mountains of Colchis, the temperate central part of the Lesser Caucasus, and the continental Javakheti Plateau. The territory of Erusheti National Park is characterized by forests, shrublands, and herbaceous communities with unique species compositions, incorporating elements of all three of these biogeographical regions. These include South Caucasian-type oriental spruce forests (Picea orientalis) and spruce–fir forests (Abies nordmanniana).
The following vegetation belts are well represented within Erusheti National Park:
- Urochloa steppes, mountain xerophytes (900–1,300 m), and broadleaf forests (1,300–1,900 m);
- Subalpine belt (1,850–2,400/2,500 m), with birch forests (Betula litwinowii), rowan (Sorbus caucasigena), goat willow (Salix caprea), high-mountain oak (Quercus macranthera), oriental spruce (Picea orientalis), and subalpine meadows;
- Alpine belt (2,500–2,950 m), represented by various types of high-mountain meadows, including grass–forb meadows, Alchemilla erythropoda communities, Nardus stricta grasslands, and alpine vegetation featuring species such as Campanula aucheri and Carum caucasicum.
Erusheti National Park represents the extreme southeastern limit of the distribution of oriental spruce. The same is largely true of its subalpine birch forests and rhododendron (Rhododendron caucasicum) communities. Oak, beech, and pine forest communities are also distinguished by their unique species compositions.
Forest Cover
Forests are widely distributed across the protected area, with distinct middle-mountain, upper-mountain, and subalpine forest belts.
- 900–1,500 m above sea level: The broadleaf forest belt includes forest formations of Georgian oak (Quercus iberica), high-mountain oak (Quercus macranthera), Caucasian hornbeam (Carpinus caucasica), European hop-hornbeam (Ostrya carpinifolia), field elm (Ulmus minor), and pine (Pinus kochiana).
- 1,200–2,000 m above sea level: Beech–oak–hornbeam forests, extensive high-mountain oak forests, and dark coniferous spruce and pine formations occur across large areas. Silver fir (Abies nordmanniana) is occasionally present. In Meskheti, beech forests form individual forest communities, primarily in association with Caucasian hornbeam (Carpinus caucasica) and oak species (Quercus iberica, Quercus macranthera).
- 2,000–2,400 m above sea level: Forests are formed by sparse, stunted birch (Betula litwinowii, Betula pendula), high-mountain oak (Quercus macranthera), and mixed oriental beech (Fagus orientalis) communities. Rowan (Sorbus aucuparia) and pine (Pinus kochiana) are also scattered throughout this belt. Hop-hornbeam forests (Ostrya carpinifolia) occur in the eastern and southeastern parts of Meskheti, extending as far as the Akhaltsikhe Basin. Their optimal distribution is in the middle part of the forest belt, where they form relatively large stands in the forests of Akhaltsikhe and the Uraveli Valley (Shetékauri & Chelidze, 2016).
The diversity of vegetation in Erusheti National Park is also enriched by various high-mountain meadows and meadow steppes.
Flora
A total of 1,652 plant species, 561 genera, and 131 families have been recorded in Meskheti-Javakheti. Of these, 843 species are common to Meskheti-Javakheti, 481 species occur specifically in Meskheti, and 336 species in Javakheti. The high-mountain flora alone, occurring above 1,700 meters above sea level, comprises 668 species.
Among the tree species included in Georgia’s Red List, the relict high-mountain oak (Quercus macranthera) is particularly noteworthy and is relatively widespread throughout the upper mountain belts of the park. Hop-hornbeam (Ostrya carpinifolia) is also notable, with forest fragments occurring in the Uraveli Valley. Other tree species listed in Georgia’s Red List and found within the national park include field elm (Ulmus minor Mill.) and walnut (Juglans regia L.).
Fauna
The Erusheti highlands are currently home to 16 species of fish, 5 species of amphibians, 15 species of reptiles, 108 species of birds, and 45 species of mammals.
Red List Species
Notable Red List species found in Erusheti National Park include:
- Mammals: Eurasian lynx (Lynx lynx), brown bear (Ursus arctos), Caucasian squirrel (Sciurus anomalus), and Eurasian otter (Lutra lutra);
- Birds: Imperial eagle (Aquila heliaca), golden eagle (Aquila chrysaetos), bearded vulture (Gypaetus barbatus), griffon vulture (Gyps fulvus), Egyptian vulture (Neophron percnopterus), ruddy shelduck (Tadorna ferruginea), and Caucasian black grouse (Lyrurus mlokosiewiczi), an endemic species of the Caucasus;
- Fish: Brown trout (Salmo trutta fario);
- Reptiles: Darevsky’s viper (Vipera darevskii), an endemic species of the Caucasus;
- Bats and rodents: Western barbastelle (Barbastella barbastellus), Nehring’s blind mole rat (Nannospalax nehringi), grey dwarf hamster (Cricetulus migratorius), and Brandt’s hamster (Mesocricetus brandti).