Caucasus

Nugzar Zazanashvili¹⁰⁸, Giorgi Sanadiradze¹⁰⁸, Alexander Bukhnikashvili¹⁰⁹, Andrei Kandaurov¹⁰⁸ and David Tarkhnishvili¹¹⁰

The Caucasus region covers a total area of some 532 658 km² in the nations of Georgia, Azerbaijan, and Armenia; the North Caucasian portion of the Russian Federation (including the Dagestan, Chechnya, Ingushetia, Northern Ossetia, Kabardino-Balkaria, Karachai-Cherkesia, and Adigea Autonomous Republics); the northeastern part of Turkey; and a part of northwestern Iran. The definition of this region is somewhat different from what was presented in Zazanashvili et al. (1999). The northern boundary still conforms largely to the original definition, but has been modified slightly in accordance with Krever et al. (2001), while the southern boundary of the hotspot intergrades with the Irano-Anatolian Hotspot to the south, in accordance with WWF ecoregions (such that Armenia now falls within both hotspots). In addition, the Caucasus Hotspot now includes the Hyrcanian mixed forests of the south Caspian Coastal Plain and northern slopes of the Elburz Mountains.

In terms of its origin, the Caucasus Isthmus is part of a huge mountain belt, the Alpine Orogene, which embraces the whole of Eurasia from the Pyrenees and the Atlas Mountains in the west to the Malay Peninsula and Vietnam in the east. It is a region of natural contrasts, and is composed of several prominent elements. These include the North Caucasus Plain (the eastern part of which is below sea level); the Greater Caucasus Range (with the highest peak being Mt. Elburz at 5 642 m); the Transcaucasian Depression; the Lesser Caucasus Mountain Chain (to 4 000 m); and the South Caucasian Uplands (covering parts of the Asia Minor, Armenian, and Iranian uplands). Glaciers are concentrated mainly in the Greater Caucasus Range, with over 2 000 of them covering 1 450 km². Not surprisingly, the climate is also very variable. Mean annual rainfall in the southwestern part of the region is quite high, exceeding 4 000 mm at some places in the coastal mountains of the Black Sea; in the eastern part of the region, on the Caspian Coast, it rarely exceeds 150 mm.

The vegetation of the Caucasus is quite diverse, including broad-leaved and coniferous forests, subalpine and alpine meadows, montane steppes and woodlands, and semideserts, and depends on both the physical features discussed above and the evolutionary history of the flora. There are two refugia of Tertiary flora in the region: the Colchis in the catchment basin of the Black Sea, and the Hyrcanian in the extreme southeastern end of the Caucasus on the Caspian Sea coast. Even now, many relict forms still appear as dominants or codominants in a number of plant communities.

Species diversity and endemism are exceptionally high for a temperate zone and relate to the geographic position of the Caucasus, which lies at the junction of two distinct zoogeographic regions: the Euro-Siberian, and Irano-Turanian. Endemic species are common in the western part of both the Greater and Lesser Caucasus Ranges, as well as in the Talysh and Elburz mountains on the southern coast of the Caspian Sea.

In terms of vascular plant diversity, some 6 400 species have been recorded in the Caucasus Hotspot, of which more than 1 600 are endemic. In addition, there are 17 endemic genera. About 35% of the endemic species are thought to have originated in the Greater Caucasus Range, and many of these are high-mountain and mountain xerophytic forms, as well as those growing on rocks and scree (Dolukhanov, 1966; Gagnidze et al. 2002). Genera with large numbers of endemic species include: Saxifraga, Draba, Delphinium, Astragalus, Rosa, Pyrus, Onobrychis, Scutellaria, Campanula, Symphyandra, Pyrethrum, Primula, Heracleum, Jurinea, Psephellus, and Cirsium. The region also harbors a remarkable concentration of economically important plants, particularly wild crop relatives, such as wheat, rye, and barley (but also fruits like walnuts, apricots, and apples).

In all, the Caucasus Hotspot has an estimated 130 mammal species; of these, 18 are endemic to the hotspot. As with other young mountain regions, the Caucasus has many newly evolved species, but also quite a few relict species as well, as evidenced by the variety of primitive species such as the unusual long-clawed mole-vole (Prometheomys schaposchnikowi), the only representative of an endemic genus, and the genera Mesocricetus, Apodemus, and Sicista. The latter genus is represented by four endemic species of unicolor birch mice (Sicista caucasica, S. kluchorica, S. kazbegica, and S. armenica); the Armenian birch mouse (S. armenica, CR) is known only from the type locality. The Caucasian tur (Capra caucasica, EN), a member of the goat family, is also endemic to this hotspot.

Bird diversity is only moderate compared to the other hotspots, with 381 species, and endemism is low, with only two endemics, the Caucasian black grouse (Tetrao mlokosiewiczi) and the Caucasian snowcock (Tetraogallus caucasicus). BirdLife International has listed the Caucasus as an Endemic Bird Area (Stattersfield et al. 1998). The Caucasus is also important for migratory species, with two major migration routes passing through the region – the east coast of the Black Sea and the west coast of the Caspian Sea. The Batumi and North East Anatolia bottlenecks are particularly good places to observe migrants. Every spring and autumn, millions of birds of several species fly over the Caucasus Isthmus en route to their winter homes. Globally threatened waterbird species in the region include the marbled duck (Marmaronetta angustirostris, VU), lesser white-fronted goose (Anser erythropus, VU), and whiteheaded duck (Oxyura leucocephala, EN).

Reptiles are represented by 87 species, of which 20 are endemic. The genera Lacerta and Darevskia, from the family Lacertidae, exhibit particular diversity: of the 60 known species in the world, 28 species occur in the Caucasus, and 15 are endemic. Several of the Darevskia species (D. dahli, D. armeniaca) have parthenogenic populations, meaning there are no males and the females are able to reproduce entirely on their own. Reptile endemics are concentrated in the xeric portions of the hotspot.

Amphibian diversity is relatively low, with 17 species, but four of these are endemic; three of these endemics are found in the forest belt in the western part of the Lesser Caucasus Range. The endemic Caucasian salamander (Mertensiella caucasica, EN), sole representative of its genus (although probably a species complex; Tarkhnishvili et al. 2000), is a graceful and colorful animal, and the best example of an amphibian flagship species in the region. The most remarkable species, however, is the Gorgan salamander (Batrachuperus gorganensis, CR), which is restricted entirely to the Shir-Abad Cave and the stream flowing from it, in northwestern Iran, and is estimated to number only 100 breeding adults.

The Caucasus region has 127 fish species, only 12 of which are endemic. Among the many interesting features of this fish assemblage are the three lamprey species: Caspiomyzon wagneri, Eudontomyzon mariae, and Lampetra lanceolata. Lampreys are ancient, jawless, scaleless fishes that date back 280 million years and have the highest number of chromosomes of all vertebrates (164–174) (Hardisty, 1986). Another ancient group of fishes that is well represented in this hotspot are seven species of sturgeon, including the famous Beluga sturgeon (Huso huso), which is the largest freshwater fish, weighing as much as 1 000 kg (Frimodt, 1995). Populations of all sturgeon species have been reduced through overharvesting, primarily for the high-value caviar, while other threats include water pollution and damming that restricts anadromous migrations (Birstein, 1993).

The invertebrates, especially insects, are diverse and, in the uplands, one can observe spectacular examples of the varied insect life, including an endemic butterfly (Parnassius nordmanni) and the Rosalia longicorn beetle (Rosalia alpina, VU). Some endemic insects are found in the foothills, including the Caucasian zerinthia (Allancastra caucasica).

Humans have inhabited the Caucasus for a very long time and, for that reason, natural ecosystems have been affected by humans in many ways. Since the social and economic crises that began in 1992, the situation in the Caucasus has deteriorated significantly. Due to a lack of energy resources, the population now consumes 200%-300% more firewood per family every year than it did in the 1980s, and illegal forest cutting and timber exports have increased as well. More than 30% of the pastureland of the region suffers from varying levels of erosion; overgrazing, mainly by sheep, in the subalpine and alpine summer ranges of the Central Caucasus and in the winter ranges of the steppes and semideserts increased by a staggering 250% at the end of the 1980s. As a result, secondary communities now occupy two-thirds of the pasturelands in the subalpine belt and arid zones. Nonetheless, pristine areas remain in a number of places, particularly in inaccessible gorges and other remote, high-altitude areas. However, looking at the region as a whole, we estimate that about 145 000 km², or 27% of the land area, remains in reasonable condition, while still less, only about 11%-13% of the original extent of natural vegetation in the Caucasus, remains in pristine condition.

Poaching is also a serious problem that increased significantly in the 1990s, with animals like the leopard (Panthera pardus), brown bear (Ursus arctos), wolf (Canis lupus), Caucasian red deer (Cervus elaphus maral), bezoar goat (Capra aegagrus, VU), Caucasian chamois (Rupicapra rupicapra caucasica, VU) and tur being most heavily impacted. The leopard is now down to no more than 40 individuals in the entire region (WWF Technical Reports 2002–2004). The Caucasian tur, which still numbered in the hundreds of thousands in the middle of this century, has now been drastically reduced because of the combination of poaching and greatly increased development of pastureland. Today, there are only about 4 000 of the eastern subspecies and 6 000-10 000 of the western subspecies still in existence (Weinberg, 1997).

Fortunately, there is a long tradition of nature conservation in the Caucasus, with the first State (Strict) Nature Reserve (Zapovednik), the Lagodekhi Gorge in Georgia, having been created in 1912 on the southeastern slope of the Greater Caucasus Range. Subsequently, establishment of strict nature reserves became a key part of conservation activities in the Russian Empire and then the Soviet Union. According to the World Database on Protected Areas, in this hotspot protected areas in IUCN categories I to IV cover approximately 6.7% of its land area. Taking into account other forms of managed reserves (sanctuaries or wildlife refuges), where some kind of protective regime is also in place, around 8% of the hotspot is afforded some form of protection. Regimes for protection generally forbid logging, drainage of wetlands, use of chemicals, and any other intensive forms of nature use, but often permit hunting and fishing.

And there are positive developments in the region, too. In a presidential statement on the occasion of the launch of the “WWF-2000-Living Planet Campaign,” a pledge was made that by the year 2010, Georgia would increase forest protected areas (IUCN I to IV) coverage to 15% of its total forest area as a “Gift to the Earth.” Azerbaijan's Ministry of Ecology and Natural Resources has been actively developing a protected areas system in the country, and several existing nature reserves have been expanded and national parks established. There are concrete plans for creating new protected areas and connecting corridors in the Caucasus part of the Russian Federation and in Armenia. Turkish activities have focused on strengthening the protected areas system, while sustainable resource use programs in the Camili region are ongoing.

In 2003, the Critical Ecosystem Partnership Fund (CEPF) began investing in the Caucasus Hotspot. A joint initiative of Conservation International, the Global Environment Facility, the Government of Japan, the John D. and Catherine T. MacArthur Foundation, and the World Bank, CEPF's five-year, $8.5-million investment in the Caucasus will target a slightly larger region than discussed here. CEPF will focus on conserving the hotspot's globally threatened species, the majority of which are found in specific sites in five target corridors: Greater Caucasus, Caspian, West Lesser Caucasus, East Lesser Caucasus, and Hyrcan. This is one example of conservation plans that have been developed for the region based on wide stakeholder involvement, but these processes are still in crucial need of further financial and technical support from the international donor community and conservation organizations.