Biodiversity

The Global Significance of Georgian Biodiversity

The Caucasus has been recognised as holding an important reservoir of biodiversity, and is indeed considered a globally significant ‘biodiversity hotspot’ based on the richness of species and level of endemism recorded. The reason for the area’s diversity may be explained by its location (at the juncture of two major biogeographic regions), the land form (the peninsula between the Black and Caspian Seas provides an important migration route and fly way), the topography of the landscape (with great variations in altitudes, and opportunities for isolation) and the climate (which varies significantly across the country, resulting in various habitats – from sub-tropical drylands and dry forests, to mountain tundra).

Floral diversity

As a consequence of its location, and its physical and climatic diversity, Georgia has a remarkably rich and diverse flora in comparison to other temperate countries. There is a high level of endemism, which includes components of various biogeographical origins. Many groups of plants are believed to have originated in the Caucasus Mountain Range and the process of plant speciation is thought to still be taking place.

A total of 6,350 species of vascular plants have been recorded in the Caucasus region, and Georgia contains 4,100 of them. Additionally, the country is also diverse in terms of taxonomic structure. The high level of endemism can be attributed to the physical characteristics of the central and eastern parts of the Great Caucasus, and to the ecological and geographical isolation of certain ecosystems.

Georgia has 300 species of vascular plant endemic to the country, and 600 more species that are endemic to the Caucasus region. Georgia’s flora also includes a number of endemic genera; 16 genera are considered endemic or sub-endemic to the country.

Faunal diversity

Invertebrates
Information on Georgia’s invertebrates is somewhat variable – some groups have been well studied, although information is almost totally lacking for other groups.

Over 11,100 species of invertebrates have been recorded in Georgia, including almost 9,150 arthropods (and of these over 8,230 insect species). Groups including many of the parasitic worms and flukes have been well studied, as have earthworms and some of the key insect groups – such as Lepidoptera (butterflies) and Coleoptera (beetles). The Coleoptera, with almost 5,000 recorded species along with Diptera (flies) and Hymenoptera (wasps and bees), show high species richness among the groups studied to date.

At this stage there is little information available on the status of individual invertebrate species in Georgia.

Vertebrates

Fish
Georgia has two main river systems or watersheds - one that drains the eastern part of the country (the Caspian basin) and the other that drains the western part (the Black Sea basin). In total 84 species of freshwater fish have been recorded in Georgia. The Caspian Sea basin has 29 species, while the Black Sea basin has 66 species (six of these are endemic to the Black Sea basin, and eleven of these are common to both basins). The Mtkvari River is of particular importance in terms of fish diversity. Twelve native species are found only in the Mtkvari River’s watershed, and nine of these are endemic to this system, including several economically important barbin species (three Barbus spp. and Varicorhinus capoeta). Other economically important species in Georgia include the sturgeons Acipenser sturio and Huso huso.

In addition to native fish species, there are nine introduced species, of which the crucian carp (Carasius carasius) has become most common. All these species were introduced during Soviet times, when there was a well-developed network of fish farms that produced fry species. These were released into both artificial and natural lakes (Lake Paravani and Lake Tabatskuri).

Amphibians
There are 12 species of amphibians in Georgia including four newts and salamanders (order Caudata), and eight frogs and toads (Order: Anura). Important amphibian habitats include the mountain forests of Colcheti as well as the Gardabani Valley, Borjomi Valley and western parts of the Meskheti range. Significant changes have been noted in the distribution of amphibian populations in Georgia. For example, populations of the Eastern spadefoot toad (Pelobates syriacus) and Mediterranean frog (Hyla savignyi) are moving towards the southeast. Georgia is the easternmost edge of the global ranges of the smooth newt Triturus vulgaris lantzi and the banded newt Triturus vittatus ophriticus. Some populations of these species have seemingly become extinct.

Reptiles
Most of the reptiles found in Georgia belong to the eastern Mediterranean biogeographical region. There are 52 species in Georgia including:

• 1 tortoise species
• 2 turtle species
• 27 lizard species (ten genera from six families)
• 23 snake species (ten genera from four families).

Of these reptiles, 3 snake and 12 lizard species are endemic to the Caucasus.

Birds
There are more than 300 species of birds in Georgia. A significant number of them are migratory. The most important bird areas are the Colcheti Lowlands (including Lake Paliastomi and the coastal zone at the Black Sea) and the Javakheti Plateau, an area rich in freshwater lakes. More than 100 species of migratory birds visit these places in great numbers.

There are three Caucasian endemic bird species in Georgia, including the Caucasian black grouse (Tetrao mlokosiewiczi), Caucasian snowcock (Tetraogalus caspius), and Caucasian warbler (Phylloscopus lorenzi).

Mammals
A total of 79 species of small mammals are recorded from Georgia, from four different orders (insectivores, bats, rodents and lagomorphs). The numbers of species in each order are presented in Table 2.1. There are several noteworthy species of small mammal including Caucasian endemics, as well as some introduced species of small mammal. Georgia’s fauna also includes 30 species of large and medium-sized mammals, including deer, gazelles, whales, and carnivores. Until the beginning of the last century many of these species were widely distributed in Georgia. For example, the Asian leopard (Pantera pardus), lynx (Lynx lynx), and wolf (Canis lupus) were found throughout the country and marbled polecat (Vormela peregusna) was found everywhere except in the humid Colcheti Lowlands ecosystems; and the striped hyena (Hyaena hyaena) was common in all arid areas of the country. Since the 1920’s, there has been a significant decline in the populations and ranges of all these species. For example, only a few individual leopards are now thought to remain in very remote and inaccessible areas. Similarly, few striped hyenas now remain and the goitered gazelle (Gazella subgutturosa) is now considered extinct in Georgia. In addition, some important populations of other species have also disappeared, including the southern population of Bezoar goat (Capra aegagrus).