CRTC for ITCAMP: Coastal Profiles. Russian Federation

Russian Federation

SECTION 3. BIOLOGICAL CHARACTERISTIC OF THE COASTAL ZONE AND BILOGICAL RESOURCES

3.1. The biological variety of the sea

The biological variety of the sea is 2,5 times poorer than the biological variety of the Black Sea or 5 times poorer than that of the Barenzevo Sea. According to the classic information of L.Zenkevich (1963) the fauna (that is the list of al animals) of Caspian Sea consists of: 62 types of the elementary, 397 invertebrate species, 79 vertebrate species and 170 species of parasitic organisms. Of those 718 species 46^ are the endemics of the Caspian sea, 66% take their origin from the neighbouring southern seas, 4,4 % have Atlantic and Mediterranean and 3% Arctic origin. One should note that the real biological variety of the Caspian Sea is not known for both plants and animals. There are a lot of new species and subspecies waiting for their description. Besides, to give a strict characteristic of the biological variety of the Caspian Sea is difficult because of the difference with the characteristics of freshwater species and forms, bond with the rivers of the basin.

The modern Caspian Sea is optimal only for the saltish species, taking their origin from both the sea and the continental water reservoirs. He fish and cancroids make the variety of the Caspian Sea, because these organisms can live in the wide range of salt waters (osmoregulatory): from the freshwater to more salty than the oceanic waters. Modern biological formation reflects the complicated history of its transgressions and regressions, desalination and visa versa.

The modern Caspian Sea, according to its origin, is a part of ancient slightly salty Pontichesky Lake, existing 5-7 million years ago. That is why the most ancient organisms are the species from the salty waters. Among them the highest percent of the endemic species and even families are noticed. Thanks to the relatively stability in time, the regime of saltiness (it is always slightly salty) and its geographical condition almost all avtokhton species are found in the Middle Caspian Sea and accordingly, the highest number of endemic species are found here. On contrary, the Northern Caspian Sea has the highest variety of places of habitation. This is reasoned by the presence of big rivers, such as Volga and Ural, thanks to the flows of which the mixture of the sea and freshwater fauna takes place. It was through the river system of Volga that Arctic and Mediterranean species could enter the Caspian Sea at all times.

Seal, white salmon, salmon, small cancroids arrived into the Caspian Sea during the period of glacial epoch from the Arctic seas. The ordinary for the seas, connected with the oceans, cephalopoda, medusoids, sponges, Polychaeta worms, polyps are absent in the Caspian Sea, but as the acclimatization measures showed, they are very well adjusting to the environment of the Caspian Sea. They do not exist due to the fact that they arrived into the Black Sea from the Mediterranean when the Caspian Sea was already isolated. That is why only the sea spine, atherine and one species of bullhead, that arrived into the Caspian Sea before it was cut from the Black Sea, have the Mediterranean origin.

The distribution of the functional-trophic groups and its separate representatives shows, that Caspian Sea is one lake ecosystem. High changeability of the resident regimes of course has assisted in formation of species with wide ecological niches and high potential biological productivity. A successful existence of this ecosystem is defined by the vast oblast of the well-warmed shallow waters of the Northern Caspian Sea. It is important to note that the Caspian Ecosystem is managed, in most of its aspects, by a human being. Regarding the sturgeon species it became one big “fish producing pool” for the common use. The support of the school of sturgeons is almost fully provided by the actions of the fish producing plants, the placement of which is justified only in the deltas of the northern adjusting Caspian. In general the ecosystem of the Caspian Sea depends on the condition of its northern defined areas of water, that are mainly in the sphere of the direct and indirect management on the basis of the economical activity.

The production features of the Caspian Sea are defined by the arrival of the organic substance with the river flow and wind (ash) sediments; organic substance of phytoplankton and high rank water flora, the development of the bacterial plankton and the destruction of the organic substance in the water thickness and bottom ground. The relation between the overall production of phytoplankton and bacterial plankton is approximately 2,2:1. The mineral feeding of phytoplankton in the process of phytosynthesis is realized thanks to the biogenic substances, pilled in the deep-water zone of the Caspian, arriving along with the river flow (in the mineral and organic forms) The organic forms of the organics go through the process of destruction and salinity with the participation of microorganisms and after that they are reachable for the use by algae.

The gross output of the primary organic substance of phytoplankton for the period between 1964 and 1984 reached 143,4 millions of tons of carbon. Along with that 19,9; 44,4 and 35,7 % of the organic substance are formed in the northern, middle and southern parts of the Caspian Sea. The raising of the level till the mark of 027,75 m the annual gross output of the organic substance in the Northern Caspian increased approximately in 1,68 times, having ended up with 47,72 millions of tons while it became 280,6 millions of tons of carbon for the whole sea. Along with that the correspondence of productivity of the sectors of the Caspian Sea changed for 29,3; 39,2 and 31,5 %. When the level raises to the mark –26,5 m per year the gross output of phytoplankton increases till 318,9 millions of tons. The high specific productivity of the Caspian is 0,5% of the overall volume of the sea and it produces from 20 to 30 % of the primary organic substance, defining the peculiarities of the functioning of the ecosystem of the Caspian Sea.

The turnover of the substance in the sea is not closed. The biogenic substances pass through the food (trophic) chains from phytoplankton and phytobentoce to fish and different ichthiofags and then are lead out from this turnover during the piling up of the sediments and then are withdrawn by the human being when trading the fish, animals and birds. The turnover of the substances in the sea is not closed.

There are more than 200 cultures of the heterotrophic bacteriums belonging to the 60 species and 22 varieties of families. The northern Caspian contains more species and varieties of bacteriums that the Southern and Middle Caspian, and that again is bound with the arrival of waters from Volga, reach with biogenic elements. Of 145 researched stamps 59 can oxidize the raw oil. All in all there are 13 species of asporogenic yeast in Caspian, belonging to 4 families. Al of them in not very big numbers are found in the Northern Caspian and some of them actively assimilate the oil and oil products. Fe- Mn- oxidizing bacterium are the most numerous and manifold in the silt of the Northern Caspian.

Overall number of the microorganisms in the waters of the Northern Caspian in the seasonally and spatially is divided not equally. The winter season is characterized as a rule by the minimal presence of bacterium. The noticeable increase of the population of microorganisms is noted in spring, however the pick of population is appearing in summer and autumn (up to 200 mln. kl/l), when the average number of bacterium is 10-20 times more than during winter period. The saprophyte bacterium in huge scales realize salinity of the organic substance and in accordance with that a special role in regeneration of biogenic elements and in the processes of the reservoir purification. Thanks to the easy accessible forms of the organic substance the main mass of the saprophyte bacterium is represented by the porousless forms.

All over the Caspian Sea there are 450 species and forms of phytoplankton. In 1986-1994 230 species of the phytoplankton were found in the Northern Caspian and 82 in the Middle Caspian. According to the latest data the composition of plankton micro algae only for the Northern Caspian more than 400 species and that is explained by the development of the freshwater forms with the growth of arrival of waters of Volga. Among the freshwater forms the first in their number are the green algae. As per the biological weight the thread algae are first in the row. Blue-green algae are represented by the freshwater and saltish water forms, but their role is not significant. The diatomic forms are widely spread and represented equally variously in all ecological groups. They occupy the leading place as per the number of species, their composition is the most stable one along the whole vegetating period. The algae rhizosalinity is the massive one among the others and was first time found here in 1934; it arrived to Caspian from Azov-Black sea basin.

The main variety of species of zooplankton is dated to the delta regions and desalinated Northern Caspian. However, the majority of autochthonous species (about 50% of zooplankton fauna) live in the waters with salt consistence of 12-23 %, and mainly in deep-water parts of the sea. Five representatives of the Arctic species are also deepwater ones and may stand a high salinity. The representatives of the Mediterranean complex are mainly aerogalines and they live in all parts of the Caspian Sea. Endemisity of plankton fauna is quite high and makes 20% of the overall number of species.

The specific content of zooplankton of the Northern Caspian counts more that 200 species. Loser to the south the change of organism complexes from saltish ones to the ones that can live in different levels of salinity and further to the marine ones can be observed. In the zooplankton of the Northern Caspian in the modern period when the water level raises in Volga the defined area of water enlarges the stable tendency towards the increase of the number of species of the freshwater complex (from 54 to 62%) is observed. For the past years 81 species of zooplankton were found and registered. The level of the development of zooplankton in 1986-1994 was 1,5 times higher than in the period of the falling of the water level (1973-1977). In Middle Caspian the qualitative composition was less various – 60 species, and mainly the copepoda cancers – up to 77 % of the overall biological mass. The maximum qualitative indicators of the biological mass and the quantity of zooplankton were noted during all years of the research at the western coast. All in all, the distribution of the zooplankton agrees with the distribution of phytoplankton.

For phytobentoce of the Caspian Sea they know 87 species of algae-macrophytos, belonging to 5 types, 8 classes, 17 orders, 24 families and 45 kins. The coastal ground flora of the Northern Caspian counts 357 species of 35 families of high rank plants. Wide-spread families are the base of it, while the prevailing living form is the grasses – 86 % from the overall number of species. The representatives of the European, Siberian, Iranian and Turan and Mediterranean flora are found here. Among them one can find very rare and endemic species.

The ground flora (macrozobentoce) of the Caspian Sea is formed by 3879 species, representatives of 13 classes. As fort he whole flora of the Caspian Sea the percentage of the specific endemism of families and species (41%) is characteristic. The endemity is characteristic for cancroids and that testifies about the fact that the ecosystems of the Caspian are very ancient. As a whole the ground flora is distributed in the following manner:

Autochthonous Caspian complex – 310 species;
Mediterranean complex -29 species;
Arctic complex - 9 species;
Freshwater complex - 31 species.

More than a half of autochthonous species is adapted to different conditions of salinity and temperature. The ground flora of the Northern Caspian in comparison with Southern and the Middle ones is poorer as per the content of species. Moving from the south to north the autochthonous Bivalvia and gasteropods disappear bit by bit. In the Northern Caspian 234 species of ground animals, 132 species of autochthonous complexes, 4 species of the Mediterranean species and none of the representatives of the Arctic species were found.

The macrobentoce of the Caspian is quite various and is characterized by the high biological mass, leaving a stable feed basis for the number of the most valuable food objects, among them bentoce eating surgeons (Table. 3.1.1). According to the data as of 1951-1963 the Caspian cancroids included 114 species. There are lots of mollusks among them – 57 to 70 % of all local autochthonous species. The ground fauna of the Northern Caspian lives through the significant changes in accordance with the vibrations of its level. Despite the fact that size of the total biological mass of bentoce is approximately on the level of shallow water years (1973-1974) and varied between 47,8 and 67,5 g/m², the cancroids (4% more), worms (60% more), chironomids (65% more) are developing more intensively in the present period. The leading species among the mollusks are Mediterranean guests mithilyaster and abra. Differing from the low water period the development of the marine species and freshwater forms is less intensive, while the biological mass is of saltish and freshwater forms of mollusks have higher indicators. The distribution of the ground of the invertebrates in mainly defined by the salinity. The biological mass of the forms of the Mediterranean complex increases from north to south and with the depth. The mass development of the majority of the species of the freshwater and autochthonous complexes is observed at the depth of less than 6 m. many species are dated to the specific types of the ground.

The increase of the level and the desalinating of the waters of the Caspian Sea carry the changes in the qualitative and quantitative indicators of the hydro bionts. In all sectors of the sea increased the significance of the organisms of the freshwater and saltish complexes. The role of the tiny food algae has increased for phytoplankton. In zooplankton there are now positive conditions for the development of the Rotifera. The level of development of the production of food of intertebrates for the Caspian sprat is stable.

The specific composition of the periphytonus (biofouling) of the Caspian Sea counts about 200 species of algae and more than 60 species of invertebrates. From the total number of all the species, noticed in the growths of the Caspian Sea only 8-10 play significant role. As it is the fauna of the growth of the Caspian Sea is qualitatively poor and there are only five species of animals-growers. The species that arrived from other places play significant role in growth. The maximal biological mass of the growth in the Caspian Sea is 7,5-10,0 kg/m². Despite the massive development the growth in the Caspian Sea has not formed fully yet.

Ichtiofauna of the Caspian Sea counts from 124 to 156 species and subspecies of fish, representing 17 families. The majority of them are the carps (33% of the overall number of all species), bullheads (28%) and herrings (14%), altogether ¾ of the ichtiofauna. Relatively high percentage compose the sturgeons (5%). 63 species and subspecies of fish (50%) are autochthonous, 5 belong to the Mediterranean complex, 2 species belong to the Arctic complex and 56 species and subspecies (44%) belong to the freshwater complex. Eight species of fish appeared in the Caspian Sea in the result of the activity of a human being (Siberian salmon, white and colorful fat-foreheads, white amur, river blackhead, gambusia and two species of gray mullet).

Table 3.1.1. Feed production of the Caspian sea and its use by the food fish.

Indicators		Years
		1986-1990	1991-1995
Total production, mln. t.	Animal Plankton Animal Bentoce	100,8 677,6	97,8 747,3
Reserves for food fish, mln. t.	Vobla Bream Sturgeon Stellate Sturgeon Anchovy Sprat Big eye Sprat Ordinary Sprat	9,2 5,5 11,9 15,8 29,5 22,3 51,3	13,3 5,2 17,5 10,8 29,0 22,5 44,5
Annual ration of food, mln.t.	Vobla Bream Sturgeon Stellate Sturgeon Anchovy Sprat Big eye Sprat Ordinary Sprat	3,9 0,8 2,3 1,12 19,7 15,4 23,1	6,6 0,8 0,85 0,338 20,0 16,1 22,8
The level of the use of food, %	Vobla Bream Sturgeon Stellate Sturgeon Anchovy Sprat Big eye Sprat Ordinary Sprat	42,4 14,0 19,5 6,8 19,5 15,4 23,1	49,6 15,4 4,9 3,1 20,4 16,1 22,8

Comparing with the World Ocean and with the adjacent seas the animal world of the Caspian Sea is poor for its species, but rich for its number of valuable food fish. For example, there 180 species of fish in the Black Sea, and 540 of them in the Mediterranean Sea and only 62 in the Caspian Sea. With relatively not big variety of the species composition the Caspian Sea is the most productive one for its ichthyological weight.

The distinctive feature of the Caspian fauna is the endemism. It is noted starting from the family and further to smaller taxonomic categories. The number of endemics on the level of the family is 8,2 %, of the species – 43,5 % and of the subspecies – 100%. 4 species of endemic families, 31 endemic species and 45 endemic subspecies of fish live in the Caspian Sea at present. The majority of the endemic species and subspecies belong to the family of the bullheads and herrings and that testifies of the energetic process of the formation of the species in these groups. Specific hydrological conditions allowed different herring groups to get formed – the connecting, semi-connecting and marine. The differences of these groups reached the level of the species and that lead to the formation of 6 new endemic species.

Along with the fish, the natural habitat of which is comparably limited there are lots of forms that perform long migrations in one of the zones of the Caspian Sea into other forms, as well as from sea into the river. The majority of the forms from the composition of ichtiofauna belongs to the category of marine and river fish, the rest belong to the connecting and semi-connecting ones (see table 3.1.2).

Table 3.1.2. The distribution of the ichtiofauna to the biological groups.

Biological Group	Species and subspecies
	Quantity	%
Marine	53	43,5
River	42	34,4
Connecting	18	14,7
Semi-connecting	9	7,4

The herrings and bullheads, gray mullets, atherina and sea pike perchs spawn in the sea mainly. The representatives of the families of sturgeons, herrings, salmons, carps, perchs and others spawn in the rivers and reservoirs. Some spawn in the sea as well as in rivers, and for some (bullheads, Caspian paunchy, ordinary sprat) spawn mainly in the sea, while the others (sazan, barbell) spawn in rivers. The composition of ichtiofauna as it was mentioned, reflects the complicated evolution of this basin. The representatives of the modern Caspian ichtiofauna first appeared 5-7 million years ago in the slightly salty Pontonic Sea. Among them there were the fish that were typical for the modern freshwater and salty waters.

In the distribution of the ichtiofauna of the Caspian as well as of all its fauna the vertical zoning is brightly expressed. The main mass of the Caspian Sea lives in the coastal zone of the sea up to 50-75 meters. The deep-sea fish prevail in their mass, mainly the sprats. The Black Sea gray mullets got adapted to the Caspian Sea very successfully in 40s.

The length of life of Caspian fish specific for each species mainly depends on the combination of the favorable and not favorable conditions of their existence, while for the food species it depends on the level of the effect of the trade. For the majority of fish the length of life is not more than 6-8 years. The sturgeons live much longer: the while sturgeon lives up till 60 years, the sturgeon lives till 40 years, and the stellate sturgeon lives 30 years. The sprats, bullheads and button heads live 2-4 years – the shortest life period. During the different periods of its life fish occupy significantly different places in the trophic chains: from low steps of the caviar and larvae and up till high levels on the adult stages of some predatory fish and bentoce eaters.

The connecting fish (vobla, pike perch, bream and others) and the river (freshwater) fish of the Caspian Sea are represented mainly by the family of bullheads, the life activity of which is bound with the lowering of Volga and Ural rivers, although you find them far away from those places (table 3.1.3). In the mouth of Volga and Terek the fish that are considered freshwater or saltish water fish are quite numerous. Those are sazan, rudd, pike perch and ling. The number of small freshwater species of fish (rudd, gustera, tench, perch, crusian) and some other big freshwater species (cat-fish, ling, sazan) in the Volgo-Caspian area do not suffer from sharp vibrations, that are characteristic for the semi-connecting fish and depend on the parameters of the spring high waters on rivers.

Table 3.1.3. Some important species of food fish, found in the waters of the Northern Caspian, the sections of the spawning and the places of their concentration. The main spawning places are given in bold.

Specie	Sectors of spawning	Dates of movement to the spawning places	Places of concentration in the sea.
Caspiomyzon wagneri	Volga, Kura, Ural, Terek	IX-XI (Volga) XI-II (Kura)	In-delta sectors
Beluga Huso huso	Volga, Kura	IX-XI, IV-V	In-delta sectors
Russian sturgeon Acipenser guldestaeti	Volga, Ural, Kura	III-X	In-delta sectors, south of the western coast
Stellate Sturgeon Acipenser stellatus	Volga, Ural, Kura, Terek, Sulak	VI-VIII	Western coast of Caspian to the south from Agrakhan p-la
Acipenser nudiventris	Ural, Volga	IV	South of the eastern coast
White salmon Stenodus leucichthys	Volga, Ural	IX-II	Northern coast
Roach, vobla Rutilus rutilus	Volga, Ural, Terek	III-IV	Spawn in avandelta; in autumn – in the in-mouth places, in summer – along all water areas on the depth of 206 m..
Aspius aspius	Volga, Ural, Terek	IV-V	Delta sectors
BreamAbramis brama	Volga, Ural	IV-V	Delta sectors
Pelecus cultratus	Volga, Ural, Terek, Kura	IV-V	In-delta sectors, passes winter in rivers
Sazan Cyprinus capro	Majority of the rivers of the basin	V-VI	Delta sectors
Ordinary Perch Perca fluvifnilis	Caspian Sea	III-IV	Delta sectors
Ordinary pike perch Stizostedon lucioperca	Majority of the rivers of the basin	III-IV	Delta sectors
Sprat ordinary Clupionella delicatula caspia	Northern Caspian, shallow waters	V-VI	Desalinated shoals, in summer in the ioen sea in the depth of 100 m, passes winter on the south, partly in the middle Caspian.
Caspian herring Alosa caspia	Avandelta of Volga	V-VI	In spring – avandelta of Volga, passes winter on the south of Caspian, migrates along the western coast
Volga herring Alosa kesleri volgensis	Volga, Ural	IV-V	In spring – delta of Volga, passes winter on the south, partly in the middle Caspian.
Black-back herring Alosa kesleri kesleri	Volga	V-VI	In spring – delta of Volga, passes winter on the south of Caspian, in spring migrates to the western coast.
Caspian salmon Salmo trutta caspicus	Kura, Samur, Terek	X-II	West and south of Caspian
Grey mullet Mugil auratus	Shallow waters in Middle and Southern Caspian	X-XI	Passes winter on the south of Caspian, in spring concentrates along the coast

The bullheads occupy a very special place in the ichtiofauna of the Caspian Sea. Their specific variety (35 species and subspecies) is compared only with the ocean basins. The degree of ecological elasticity of these fish is also very high. However, these dominating species are not very numerous in the Northern Caspian Sea.

The representative of the class of atherion likes - Atherina bogeri caspia, is the endemic of the Caspian Sea, and it is wide spread all over.

At present the connecting herring is represented by one subspecies: the black back herring.

There are 6 species of sturgeons in the Caspian Sea. This is an ancient phylogenetic group. There is no other place in the world with such a big variety of sturgeons. The presence of the branch and wide river systems such as Volga, Ural, Kura and others, allowed the richest variety of species and ecological variety of sturgeons to live in the Caspian Sea. Besides, there are subgroups in each species and they differ in their spawning places and the places of resting. This lead to the maximal assimilation of Caspian resources by sturgeons. All this testifies of the ancient age of the Caspian Sea and its uniqueness as a natural laboratory where there are the conditions to preserve the ancient group of sturgeons as well as to allow other fish groups to develop themselves (bullheads, herring).

The wide natural habitat in rivers, flowing into the Caspian Sea. High supply of food in the reservoir itself allowed the formation of the biggest cattle of sturgeon fish here. The sturgeons on the north-east of the Caspian and in the basins of Volga and Ural are represented by the following species: white sturgeon, thorn, sterlet, Russian (north-Caspian) sturgeon, stellate sturgeon. Sterlet is a typical river fish. Each species of the sturgeons has very complex population structure. The populations are “bound” with the separate spawning natural habitats. At present there are minimum 20 isolated populations of sturgeons in the basin. However, the food meaning is kept only by the Volga populations of stellate sturgeon, Russian Sturgeon and white sturgeon and Ural populations of the white sturgeon and stellate sturgeon. Actually the trade is based on two species: stellate sturgeon (Volga, Ural) and Russian sturgeon (Vola population), giving not less than 85% of the whole catch of the Caspian sturgeons.

Russian sturgeon is represented by two populations – Volga and Ural ones and by two seasonal races – spring and winter ones. As per the character of feeding, the sturgeon is bentoce-mollusk eater. The main part of its life sturgeon spends in sea, and having reached the older ages it travels to Volga, Ural, Kura and Terek for spawning. At present there are 22 spawning places of the total square of 372,1 ha functioning in Volga. In Ural the total square of the spawning place covers 226 ha. In other rivers of the basin the natural production of the sturgeon is almost absent. The share of young and non-food species of the sturgeon population has increased, the indicators of the absolute length, mass and age of the fish has decreased, the percentage of the relative and absolute number has decrease too. The absolute number of the developing sturgeon had decreased from 60,5 million to 21,2 in 1994.

The white sturgeon is represented by three populations: Volga, Ural and Kura. The share of Volga population in 1989-1990 was 54%, of Ural - 43,2-44,0%, Kura-2,8-1,5% from the number of all sturgeon in the sea. In 1992 the Kura sturgeon was not met in trawl conditions, while the absolute number of the Volga sturgeon had even increased. The winter race prevails in the population (up to 80%).

The marine food species of fish are the sprats, herrings (Caspian, southcaspian), gray mullets. The natural habitats of these species cover all the natural habitats of the sea, but with quite significant differences. The shallow water northern part of the has an important role as the region of production of marine species, their development on early stages of onthogenesis and is less significant as the developing living habitat for adult fish. The ordinary sprat, dolgin herring, Caspian and big-eyed paunchies belong to the reproductive species of the Caspian Sea. The Caspian species do not have brightly expressed winter period and that is explained by the favorable climatic conditions, providing the development of the food organisms and active feeding of fish all year long. Middle and Southern Caspian play important role as the developing natural habitat.

Caspian seal, the endemic of the Caspian Sea, is mainly ichtiograph with high plasticity of the feeding. It has long trading history, with raisings and fallings down within 2-3 centuries. In XX century the trade size was hundreds thousands heads. Tough regulation and the change of the profile of the trade onto the fur increase, realized in 1966-1970 allowed to stabiles the number of the population of the Caspian seal on the level of 500-600 thousand heads with the matrix cattle of 90-100 thousand reproducing females. In 1986-1989 the number of the females decreased to 30-40 %. During the last decade the definite destabilizing processes have been noted in the population of the Caspian seal. The number of heads in the population decreased for 20%. He crisis of reproduction of the population, in its turn, is the result of the unfavorable processes, happening in the ecosystem of the Caspian Sea. During spring-summer seasons massive death of seals was noticed on the living habitat of the Northern Caspian. The reasons are not clarified fully as yet.

The variety of saltiness in the vast, wide scale of its varieties in time, big variety temperature conditions during year and, in general, the fact of high opening of the ecosystems define the wide possibilities to bring in new species, possibly resulting with the structural and quite unfavorable changes of the ecosystems. The incomers of the Caspian Sea are quite well known. Policheta from the family of Sabellidae - Manayunkia caspia quite possibly entered the Caspian Sea from Arctic. Recently two more incomers from the Black Sea entered the Caspian Sea. Those are plankton Copepoda: Calanipeda aguaedulcis and Acartia clausi. The incomers from the Atlantic and Mediterranean would appear again and again in the Caspian Sea and that would definitely lead to the processes of the setting of the new balance between the aboriginals and the incomers.

The biggest worries are bound with the appearing of the an incomer, that arrived into the Caspian Sea in XX century - (Mnemiopsis leidyi). This species-incomer comes from the saltish basins of the Northern America and is known from the heavy consequences for the ecosystem of the Black Sea, where it has significantly changed the trophic connections with the ecosystems and its commercially important biological food production in the 90s of XX century.