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Biodiversity and life resources 1. Record of mammals, birds, reptiles, amphibians, fish, invertebrates and plants. Representatives of sea, brackish and freshwater flora and fauna inhabit the Caspian Sea, which are characterised by formation of new species that emerged after isolation of the Caspian from other seas. On the background of general impoverishment of marine flora and fauna, the sea became rich with them due to speciation with emergence of new endemic species. Hence, the Caspian is one of the world’s unique brackish reservoirs, abundant with endemic species (Kasimov, 1987, Scientific basis .., 1998 et al). The considered area is not an exception due to its biodiversity, its full description is provided below. 1.1 Mammals – Mammalia Only one representative of the family Phocidae – the Caspian seal from the genus Pusa, inhabits the Caspian. Caspian seal – Phoca caspica Gmelin, 1788. Phoca caspica is found all over a year, but their number is changing. In summertime, they mainly conduct a pelagic mode of life, when they feed strongly. During this period their population reaches 70-80 individuals on the Mikhaylov’s islands and the Krasnovodsk spit. Just a few seals occur in the recreational zones, in the vicinity of Avaz and Thermoelectric power plant. Seals start to migrate northward, to places covered with ice in winter, where they reproduce, when autumn comes. However, increase of island populations (150-200) is observed in this period (Bychkov et al, 1985; Lisitsina, 1995). Sea population on Mikhaylov’s island increase to 3 thousands in wintertime (end of January, beginning of February) (Bychkov et al, 1985; Lisitsina, 1995), few females (2-6% of rookery population) bear offspring on sandy strand. Preservation of a unique, reproducing onshore (geophilous) group of Caspian seals on Turkmenistan islands is necessary for sustaining genetic diversity of this endemic species. The following onshore mammals were found in the studied area:
Population of the above animals is sufficient, biology and ecology is well-studied (Mammals of Turkmenistan, 1995; Resource species…1998, etc). Commercial species (fox, wild cat, etc.) used to be intensely developed and only in recent 10-15 years their catches have dropped for different reasons. Goitred gazelle – Gazella subgutturosa Guldenstaedt, 1780 is a valuable commercial animal, which has been hunted from ancient times for its meat and hide. As a result, their population has drastically fell and the hunt for gazelle was completely prohibited in Turkmenistan from 1950. However, attempts to eliminate poaching failed and their population had been diminishing till the end of 70s - beginning of 80s. Then the population became stable and animals survived in places, where hunting using transport was complicated. Sanctuaries needed for preservation of goitred gazelles. As a result, 13 mature goitred gazelles, 8 females and 5 males, were delivered by helicopter from Badkhyz to Ogurchin Island in April of 1983 under leadership of Kh. I. Atamuradov. A systematic growth of population with the coefficient 1,6-1,8 occured during the ensuing 5 years, and according to the reported data, their population measured up to 1 500 heads in 15.12.1999. In correspondence with preliminary calculations, poor pastures of the island can’t withstand any additional increase of load. Goitred gazelle as a rare and endangered species was listed in the Red Book of IUCN and Turkmenistan. 1.2 Birds – Aves Eastern coast – the Tukmenbashi bay holds the first place according to population of wintering waterfowls in the Middle Asia. They are the most abundant class of vertebrate animals of the Khazar reserve. To date, some 80 bird species, which are related to 12 orders, were found in the reserve (Attachment 3).
Because of geographical location, eastern Caspian wintering grounds of the Khazar reserve are on route of migration of West-Siberian, Caspian and Nile populations of waterfowls and water-loving birds, being a transit point during migration and the biggest wintering ground in Paleo-Arctic. Species composition, population, location of waterfowls and water-loving birds, which wintered or migrated to south-eastern Caspian during 1995-1996 are given in Attachment 2. 1.3 Reptiles – Reptilia 31 species of reptiles were found in the investigated range. Most wide-spread are:
1.4 Amphibians - Amphibia The following species were found in the area:
Biology, ecology and spread of both special was quite well studied (Annakuliyeva, 1974; Atayeva, 1979). 1.5 Fish – Pisces. Ichthyofauna of the Caspian basin is not distinguished by diversity of species in comparison with southern European seas. 124 fish species and subspecies, which refer to 17 families and 53 genera, inhabit the Caspian (Table 10). Table 10. Caspian Ichthyofauna
Presently, the ichthyofauna of the basin of the Caspian Sea is quite well studied. It is necessary to clarify species composition of herring, goby and other families. However, we shall expect rather decrease of number of forms, since many of identified species of herrings and gobies are morphologically hardly distinguishable. 1.6 Invertebrates – Invertebrata 1394 species of invertebrates, which constitute 77,1% of the total fauna, range in the Caspian Sea. Of these, 1069 – free-living and 325 – parasitic species. Attachment 3 contains complete taxonomic composition since there were no special researches on spread of invertebrates in the considered area. As it shown in the provided materials, the most numerous amid invertebrates of the Caspian Sea are flagellates, infusoria, roundworms, rotifers cladocerans and freshwater shrimps, whose total number constitutes 734 species or 52,6% of the total invertebrates of the sea. The role of these animals in the ecosystem of the Caspian Sea is enormous. They participate in self-purification of seawaters, in majority they serve as a fodder base for fishes, birds and other animals. Besides, they (for example, decapods, molluscs, etc.) are a valuable protein product and are actively exploited. 1.7 Plants 1.7.1 Algae 728 species and subspecies of algae and 5 species of higher plants are found in the Caspian Sea (Table 11). Table 11. Flora of the Caspian Sea
Caspian flora as well as fauna endured root changes under the influence of repeated salinization and freshening that led to supplement of freshwater species and extreme scarcity of marine species. Many alga groups, typical for seas with normal salinity, are absent in the Caspian. If red algae are predominating in the Mediterranean and Black seas, diatom, green and blue-green are prevailing in the Caspian. Eelgrass zostera invaded the Caspian in Post-Khvalyn period through Manych strait, whereas diatom rizosolenia entered the sea from the Black Sea via the Volga-Don channel in 30x, beginning of this century. Presently, diatom is ubiquitous in the sea and it is drastically altering composition and distribution of phytoplankton due to high population and biomass. All five species of higher aqueous plants were found at the bottom of the Turkmenbashi bay, of these naiads, eelgrasses and pondweeds are prevailing. Almost the whole northern and eastern coast of the Turkmenbashi bay is covered with bottom vegetation. Stonewort is spread on alluvial grounds. Stonewort form a thick green blanket from the Saimonov’s bay up to the promontry Kuva-Singer and further easward along the Balkhan bay. Red alga - polisophonia is spread mainly on sandy ground. Two species of green alga, one species of stonewort, four species of red alga and two species of higher aquatic plants, whose biomass reaches 1,9 kg/m2, are fount in phytobenthos of the gulf. Phytobenthos of the Caspian Sea plays an important role in its biological productivity. Many invertebrate and vertebrate species feed on phytobenthos, besides it serves as a refuge for them. 1.7.2 Flowering plants The coastal flora is represented by 153 species of higher plants. The following families are predominating:
Grass (86% of species) predominates in biomorphological range of communities; subshrubs and shrubs constitute 6%, trees – 0,5% of species. Major part of terrestrial plants constitutes those representatives of desert zone. Halophilic plants - sarsazannik, selitrannik, Caspian astragal, interglifolit develop in inter-sand hill depressions of north-western stretch of the area; comby tugay and haloxylon on the Krasnovodsk spit. Wormwood and saltwort are spread all over the area. 2. Species composition and state of endangered species 2.1 Birds - Aves
2.2 Fish – Pisces
2.3 Invertebrates – Invertebrata 2.3.1 Insects – Insectia
3. Endemic species and subspecies Brackish water-dwellers are the most ancient inhabitants of the Caspian, the highest number of endemic species and genera are found among them. The remaining organisms originate from the following three main sources:
The list of endemic species and subspecies of invertebrate and vertebrate animals and of higher plants, ranging or migrating to eastern coast of the Caspian, is provided below. 3.1 Mammals - Mammalia
3.2 Birds - Aves
3.3 Reptiles – Reptilia
3.4 Fish – Pisces
3.5 Insects – Insecta 3.5.1 Coleopterans – Coleoptera
3.5.2 Click-beetles – Elateridae
3.5.3 Darkling beetles – Tenebrionidae
3.5.4 Snout beetles – Curculionidae
3.6 Higher flowering plants
4. Primary threats leading to extinction of coastal species In connection with the Caspian transgression, nesting grounds of the colony of sandwich tern (Sterna sadvicensis), which constitute one fourth of the world population, are in peril of extinction at reserve islands Osushniy and Mikhaylov’s (Krasnovodsk Spit). Nests of sea pigeon (Larus genei), river tern (Sterna hirundo) and Chegrava (Sterna tschegrava) are also flooded. Wetlands of the Khazar reserve, which are of international importance as a habitat and wintering ground for waterfowls and water-loving birds, are being also flooded. Pollution of surface waters, as a result of increased activities on prospecting and exploitation of oil fields and closeness of their communications, is observed on coastal strands, in places of mass migration and wintering of birds (5-6 months a year). Oil products, pesticides and other detrimental substances that are discharged into the sea have a toxic effect on fries and fingerlings, destroy their fodder base. Hence, the population of sturgeons and other valuable fish species is drastically dwindling. Another important reason for disappearance of animals is poaching on sturgeons and illegal shooting waterfowls after ending of hunting season. Increasing anthropogenic activities (development of quarries for extraction of construction materials, overgrazing, lying oil and gas pipelines, construction of motor roads, etc.) exert certain impact on the state and dynamics of populations of some species and influence on formation of coastal biological communities. 5. Vulnerable species and biotopes Presently, the following species of animals are in critical condition:
Vulnerable plant species, ranging on the coast, and land vertebrate and invertebrate animals need to be further studied, because scientific observations on their actual state have not been carried out for the last five years. 6. Trophic facets 6.1 Nourishment, food prey-predator relations Nutrition – one of the most important processes of an organism, which carries out its main function at the expense of energetic substances received from the outside: development, growth and reproduction. Since the species are not isolated in the wild nature, so a certain type of interspecific connections comes into existence among them. One of the crucial relations both within and between species, are food relations. For instance, in the course of assessment of the fodder base of water reservoirs and feeding conditions of hydrobionts, we shouldn’t base only on data on the amount of available or created food. In this case, we mean a complex biological phenomenon, when consuming and consumed organisms (i.e. predator/prey) aren’t related by a simple quantitative relation, but first of all by contradicting relations of preying and escaping, which are manifested in diverse forms of adaptation, historically developed by each party. It means that behaviour of food consumers is formed on the basis on adaptations to catching its quarry and simultaneously protecting itself from being a prey of other animals. So there created a peculiar system of triotrophs. For example, fish-planktofags (sprats, etc.) are feeding on plankton, in the same time they serve as food for predators (strugeons, etc.). Their migratory behaviour should be regarded as a triotroph. There are three main groups of organisms in the wild nature: producers, supplying primary production (green plants and bacteria); consumers, consuming primary and secondary production, i.e. using ready organic matters (animals, parasitic plants, etc.); reducers (destructors), living at the expense of dead organic matters. In turn, consumers are subdivided into three subgroups: I level consumers – plants and phytofags; II level consumers – predators and parasites, feeding on plants; III level consumers -–predators and parasites. However, this division is conditional (Voronov et al, 1999). The Caspian seal is the only mammal of the Caspian, which is one of the final trophic links of the reservoir. Its influence on stocks and dynamics of fish populations is in some cases a decisive biotic factor. This only can be compared with anthropogenic influence. The major part (89,4%) of population diet is consumed in feeding period, which lasts for 5-6 months, from May to October. Sprat is the main food. It works out to 80% of summer diet. 6.2 Food chain Trophic (food) chains form a consequence of hierarchic levels, starting from the level of production followed by several levels of consumption. They can be divided into three foremost groups:
The Caspian seal has practically no enemies in the aquatic environment of the Caspian Sea. It is more vulnerable onshore due to morphological and functional structure. Cautious animals arrange their rookeries on gently sloping denuded islands and quickly swim away in case of any danger. The white-tailed sea eagle always occurs along with breeding grounds. Wolves, foxes and racoon dogs often attend rookeries, inflicting heavy damage to young populations. Thus there is a trophic chain: phyto-, zooplankton; sprat; Caspian seal; humans and land animals of prey. The trophic chain of land animals is also clearly seen. For example, fox – is representative of omnivorous animals and it feed on very diverse food of animal and vegetable origin, however in the Caspian region its main food is rodents. In turn, wolves, hyenas and big birds of prey feed on foxes. In this case, the food chain looks as follows: rodents; foxes; men, wolves and hyenas. Based on how diverse is animals’ nutrition, they are subdivided as follows: euryphagous - able to eat a varied diet; stenophagous – feeding on small variety of different things; and monophagous – eating one food only. Type of nourishment is a specific quality, which shaped in the course of speciation. The more stable are feeding conditions of a species, the less diverse is food of a species and on the contrary the more variable is the fodder base, the more diverse is food of a species. 7. Existing reserves The Khazar reserve of the Ministry for Nature Protection is located at south-eastern coast of the Caspian at the territory of Turkmenistan. It was set up in 1968 and is a natural complex of deserts, arid subtropics and marine shoal bays. The reserve consists of two stretches. The Turkmenbashi part (192 thousand ha) includes waters of Turkmenbashi, North-Cheleken, Balkhan and Mikhaylov’s bays bordered with a one-kilometre desert and salina strip. The Esenguly stretch is an oasis in lower reaches of the river Atrek and marine shoals (70 thousand ha). Wetlands of the reserve are included in the Ramsar Convention, since they are of “international importance mainly as a habitat of waterfowls”. More than 280 species of birds (almost a half of these are waterfowls and waders), about 40 species of mammals, 31 snakes and lizards, 2 amphibians, more than 20 fish species and more than 400 species of higher plants dwell in the reserve. The central office, laboratories and a museum are sited in the city of Turkmenbashi. The reserve is a research institute in compliance with its legal status. The main goal of the reserve is to protect and comprehensively study natural complexes and ecosystems of eastern coast of the Caspian Sea, nesting and wintering grounds for waterfowls and other valuable and rare birds. Ogurchin preserve, with the total area of 7 thousand ha, is located on eastern coast of the Caspian Sea, 30 km south of the city of Khazar on island Ogurchin. The preserve is under authority of the Khazar State Reserve of the Ministry for Nature Protection of Turkmenistan. The preserve was established in 01.02.1982 for protection, preservation, improvement and study of natural complexes representative of Caspian coasts. 8. Exotic species Invasion of exotic (strange) species is one of the factors of man-made impact on the ecosystem. The main route of for penetration of exotic species into the sea is aqueous. Organisms can travel with growth on underwater parts of ships and in ballast tanks. These are algae, molluscs, balanuses, pearlweed, etc. Presently, as a result of active development of aquaculture, the bred organisms along with their diseases, parasites and other biota related to them, can be transported from one continent to another within a few flight hours. Thus, the number of potentially invading species is increasing. The process of invasion of aquatic animals in new regions is accelerating world-wide and geographical isolation of continents as a binding condition of global biological diversity is being violated. Mediterranean species, which spread into the Caspian after erection of the Volga-Don channel, are exotic species. Conopeum seurati, Mercierella enigmatica, Berentsia benedeni, which came with growths on underwater part of ships in the end of 50s, are now adversely affecting ship bottoms, piles and other parts of hydrotechnical constructions due overgrowth. Owing to expanding ways of spread of exotic species, they can enter new habitats by different means. For example, mollusc Mytielaster lineatus, a coloniser from the Black-Azov seas, appeared in the Caspian in the end of 30s, during transportation of launches from Batumi by railways. It successfully adapted to new conditions, intensely multiplied and took important place among Caspian groundlings, playing a significant role in self-purification of seawaters. Some hydrobiont species were purposely introduced into the Caspian. Of these with the purpose of increasing fish productivity the following species were introduced: Black Sea plaice Pleuronectes flesus luscus in 1930-1931; mullets – Liza (Mugil) auratus and Liza (Mugil)saliens 1930-1934. Nereis diversicolor and Abra ovata were introduced from the Sea of Azov to increase the fodder base in 1930-1934. Analysis of species composition of Caspian exotics, conducted on the basis of available published data and own materials, revealed a wide range of species introduced during the XX century – from representatives of phytoplankton to fish (Kazancheev, 1981; Yablonskaya et al, 1985; Kasimov, 1987; Belayeva et al, 1989; Berdiyev, 1992; Aladin, 1999). We discovered more than 30 introduced species, almost all of them are found in the considered area. Their list is provided below as they entered the Caspian:
One of undesirable invaders was the three-spined stickleback discovered in 1981, which can be found in the vicinity of Ufa and Tukmenbashi. Three-spined stickleback, being an euryphag with no commercial value, is a competitor for youngs of other fish species, and feeding on fish eggs and larvae of commercial fish species, by this inflicting considerable damage to fisheries and stocks of valuable fish species. It was noted that one stickleback devours 74 fries (6mm) during 5 hours, and then another 62 fries in two days (Zhukov, 1988). Also an important fact is that when entering hydrological installations of thermoelectric power plant, stickleback considerably lowers their efficiency. Taking into consideration that stickleback is infected with taeniae in many water reservoirs and is an intermediate host of warm invasions, it was proposed to carry out urgent actions for diminishing stickleback populations by catching in lower reach of fishways and in remaining water reservoirs after desiccation of spawning grounds. Invasion of snakehead – Channa argus spp. also poses negative consequences, being an active predator it can adversely affect populations of valuable commercial fish species. The most dangerous representative of exotic species is Mnemiopsis leidyi, discovered all over the Caspian in 1999. Unless we find measures to decrease its influence on the Caspian ecosystem, the Caspian may face quite dreary consequences. We have examples of the Black Sea and the Sea of Azov (Volovik, 2000). |
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