THE YEAR 2020 … The Caspian – a Dead Sea

The travels of plants and animals from continent to continent create a host of problems in the places where they arrive. The textbook example is the havoc the rabbit wreaked in Australia. Everyone who watched the opening ceremony of the Olympic Games in Sydney remembers the unprecedented safety measures taken with regard to sport horses and even foodstuffs. Ambrosia is not only the mythical food of the Greek gods, but also a weed plant and a very powerful allergen that invaded Europe from America. The Colorado potato beetle arrived by the same route and is now familiar to every dacha owner. The troubles caused by aquatic animals are not as widely known, but the damage they do is often more tangible. The economic problems that the wandering zebra mussel from our rivers created for Americans are estimated at 5 billion dollars for the year 2000 alone. The rotan fish, which previously lived in the Far East, is now known to every angler, since it takes the place of more valuable native fish in a body of water. A similar calamity in the Volga delta is the Far Eastern crucian carp, which the locals call "buffalo". The bullhead fish comes from North America, but fortunately is absent from the Volga.

The first invader, the Mytilaster mussel, was brought to the Caspian during the Civil War years with military boats from Batumi. Nobody calculated how much that cost, just as nobody counted the deaths in the fratricidal war. Within a few years Mytilaster had done away with two species of Caspian zebra mussels. All that remains of them in zoological collections as a memento are their shells. The occupier's success was largely aided by the collaborationism of the sturgeons, which did not want to eat the exotic food. That is how the first Caspian food dead end appeared. After the Volga-Don Canal opened, dozens of species made their way into the Caspian, and just as many freshwater ones settled in the Volga. Some of them pose a serious threat not only to fisheries, but also to you and me. For example, the Lithoglyphus snail brought with it into the Volga basin two parasites that are dangerous to humans. Nor did Fadeev's leeches, which have spread throughout the whole cascade of Volga reservoirs, improve the situation. In the Caspian, as everywhere else in the world, biological invasion has long since become not only a serious biological problem, but an economic one as well.

The fisheries organisations of the Caspian states, busy pumping money out of oil companies for environmental work, did not want to pay attention to this problem. True, until very recently the biological invasion was not catastrophic in nature. Now the apocalypse has begun. In 1999 the first comb jelly Mnemiopsis was recorded in the Caspian, and by autumn 2000 it had spread practically throughout the whole body of water. We predicted this event, with its grave consequences for fisheries, in 1995. But as far back as the late 1980s the comb jelly had demonstrated the seriousness of its intentions, first in the Black Sea and then in the Sea of Azov. So the terrible jelly-like predator did not get into the Caspian from the distant Atlantic, as the director of the Caspian Research Institute of Fisheries (KaspNIIRKh) V.P. Ivanov imagines. It came from the Azov with the ballast water of ships that had passed through the Volga-Don Canal. The impending disaster could only have been prevented before Mnemiopsis arrived. To do that, it was necessary to organise a quarantine for ships or ensure their tanks were flushed with fresh water from the Don. This was proposed repeatedly, the last time in 1997. At present Mr. Ivanov plans to bring other predators into the Caspian to fight the approaching danger. Of course, one can understand him. Very soon the five hundred employees of his institute will have nothing to study, forecast or reconstruct. Unless, that is, the North American paddlefish, brought into the Volga delta by his staff for yet another experiment on nature, gets out of control. So what are these terrible predators that now threaten the Caspian and that are our allies?

The biological threat and hope in facts and figures

Comb jellies are jelly-like animals, the closest relatives of jellyfish. They got their name from the hundreds of tiny oars – comb plates arranged in eight rows over the whole body from the crown to the mouth. In the light the plates shimmer with all the colours of the rainbow, and at night comb jellies glow like Chinese lanterns. An amazingly beautiful animal! But only in the sea. When you try to catch them, they turn into a shapeless little lump of slime (jelly), 97% of which is water. The comb jelly Mnemiopsis grows up to 12 cm. and in appearance most resembles a walnut shaped like the heart on a Valentine's card.

Before its invasion of the Black and Azov Seas, Mnemiopsis lived off the Atlantic coasts of both Americas. It lived between the Roaring Forties at water temperatures from –0.7 to 35оС. It was found both in almost fresh water and in water twice as salty as seawater. Anyone can taste it by dissolving 70-75 grams of salt (2.5 tablespoons) in a litre of water. The little lump of slime is indifferent to a lack of oxygen in the water and to its pollution. During reproduction, each individual that has reached 1.5-3 mm produces from 2 to 14 thousand eggs, which in a day or two become young comb jellies. The youngsters grow very fast. They need 8-12 hours to double in size, and a week later they have grown a hundredfold. Naturally not on manna from heaven. It prefers meat delicacies to plant food. It eats fish roe, fish larvae and tiny animals floating near it in the water column, in short everything smaller than 1-1.5 cm. that sticks to its hands, or rather to its catching tentacles. Its daily bread amounts to up to 40% of its own weight each day. Compared to it, a wolf is a harmless lamb. Mnemiopsis, while holding a hundred victims in its tentacles, can digest only one. When left without food, it shows Spartan patience and stays alive for a long time, although it loses a lot of weight. The vitality of Mnemiopsis is the calling card of its origin in one of the salt-forming basins off the shores of the American continent.

In its native habitat, the development of Mnemiopsis is kept in check by two species of jellyfish, the Beroe comb jellies and butterfish. In the Caspian it has no natural enemies, just as none turned out to exist in the Azov–Black Sea basin. There it was noticed in 1987-1988, and its biomass has now reached 900 million tonnes. That is ten times the annual fish harvest of the entire World Ocean! This plague-like phenomenon has led to losses in the billions as a result of the almost complete halt of fishing on two seas. From 1990-91 to 1996, catches of Black Sea anchovy, sprat and tyulka fell from 190-160 to 15 thousand tonnes a year. The comb jelly has also affected the stocks of other commercial fish.

Only in the very last few years has the arrival of Beroe comb jellies been recorded in the Black Sea. In Ancient Greece, Beroe was the name of one of the nymphs, the daughters of Oceanus. The comb jellies on which hopes are pinned in the biological war on the Caspian are not so graceful. In shape they resemble a wine glass, a cucumber or a bishop's mitre. In substance they are one enormous gullet that feeds almost exclusively on other comb jellies and only occasionally eats jellyfish. However, the capabilities of the potential enemy are far more modest than those of its prey. Beroe will most likely be unable to live in the less saline waters of the Caspian, just as they avoid the relatively fresh Sea of Azov. Besides, the comb jellies opposing their relative in the Black Sea are native Mediterranean dwellers. And there, even in winter, the water temperature over most of the sea does not drop below 13оС. The Caspian has no resort conditions like Turkey and Italy prepared for it. Of the subtropical species, only a single species of red algae and the mullet have managed to take root here. So if we are to look for allies against an alien invasion, it should be in the native habitats of the ancestors of the Caspian fauna – in the North Atlantic and the Arctic. The origin of the Caspian's flora and fauna is no less fascinating than a detective story, but that is a topic for another publication. Several million years of evolution of the Caspian's inhabitants will, in the coming years, be wiped out by one single species that will turn the largest lake in the World into a dead sea. There is no hope that things will turn out differently. Almost none …

The devil is not so terrible as his little one

How many millions of tonnes of slime are now floating in the Caspian, nobody knows. The system of biological monitoring of the state of the Russian sector of the Caspian is in a condition comparable to the years of the Civil War and the Great Patriotic War. Roshydromet's biological monitoring network has ceased to exist. The range of observations at the Astrakhan Biosphere Reserve has shrunk. The results of work carried out by KaspNIIRKh are traditionally published after a long latent period in the form of abstracts, and the archive materials are closed. Data exchange between organisations of the Caspian states has never been established. One thing is clear: in a few years the total mass of Mnemiopsis will exceed a billion tonnes. Over the course of a year, what is already there destroys the organisms drifting in the water column that herring and kilka fed on. Their roe, larvae and fry are seen by this voracious gourmet not as future delicacies for our table, but merely as its ordinary food. What the comb jelly has eaten this year, Caspian fishermen had planned to catch in 2-3 years. Now they won't. There are fish in the Caspian now, but that is small consolation. Kilka live no longer than 7 years, and only up to the age of four are they of commercial interest because of their sheer numbers. Herring that live to 10 years are venerable old-timers. The young herring and kilka not eaten by Mnemiopsis will constantly find themselves in an unsporting competition for food resources. That will add neither weight nor fat to them.

Mr. Ivanov's attempt to explain this year's sharp drop in kilka catches by the atrocities of Mnemiopsis is what you'd call shifting the blame onto someone else. Either that, or admitting that the fishing vessels on the Caspian are destroying the young fish. Kilka in the Caspian really are harvested in a barbaric way, sucked out of the water column with pumps. For this reason, Caspian fishermen will feel the depletion of its shoals sooner than their Black Sea colleagues, who fish with nets. The drop in catches in 2000 is more likely an ordinary forecasting error caused by an abnormally warm winter. Not the first, not the last, and far from the only one. The reason is the complexity of the Caspian's biological system. It is so poorly studied that the experts of the Caspian states who gathered in Alma-Ata in July 2000 were forced to admit it. I will be glad if my forecast doesn't come true either, because behind the catch figures lie the fates and well-being of hundreds of thousands of people engaged in breeding, catching and processing the fish wealth of the Caspian. In 1998, vessels of all the Caspian states caught 195 thousand tonnes of kilka, which is comparable to the catches of plankton-eating fish in the Azov–Black Sea fishing area in the early 1990s. The barges full of Black Sea mullet that the famous Kostya brought into Odessa have remained in a beautiful song. Soon not only the Caspian sturgeon but also the kilka will be the stuff of legend.

The loss of commercial concentrations of kilka may occur within the next 4-6 years. In the same period, or a little later, the commercial stocks of Caspian brackish-water herrings (330 thousand t in 1998) will be undermined. More distant indirect consequences will be a decline in the populations of beluga and seals, which feed on kilka and herrings. Because of this, their competition for food (the remaining herrings and gobies) will intensify, and as a consequence stocks and catches will fall further. The remaining seals and beluga will migrate to the Volga estuary area – the feeding grounds of the so-called "semi-anadromous" fish. Because of this, catches of "small" and then "large" chastik will decline. Beluga in these places will come under heavy poaching pressure. In the long term, beluga and seal may be completely lost as commercial species. Later, perhaps, there will be no Russian sturgeon or stellate sturgeon left. Or rather, single specimens will be of zoological interest. In 2000 this already happened in the Azov basin, where Russia has stopped commercial fishing of sturgeon. According to the optimistic forecast, the Caspian will completely lose its fishery value between 2020 and 2025. Even if the enemies of Mnemiopsis manage to take hold in the Caspian, this will not fix the situation. We will only add one more link to the food dead end. Given that the depletion of the Caspian's fish wealth is currently proceeding at an accelerating pace, Mnemiopsis will speed these processes up even more. This has been observed after every introduction of alien organisms into the Caspian.

All creatures come visit us

In the early 1930s, mullets were acclimatized in the Caspian; like the Beroe now appearing in the Black Sea, they are Mediterranean species. In winter they leave the Black Sea, migrating south, and in the Caspian they concentrate off the southern shores. That is exactly where Iranian fishermen organized a fishery for them. Soviet fisheries science turned out not to be up to it. Why were they brought over from the Black Sea basin? Probably out of a desire to remake everything. And back in those years it was customary to overfulfil plans. So, on the initiative of a group of technical staff who were transporting the mullets, two species of shrimp appeared in the Caspian. To this day nobody knows why, just as nobody has any idea of their role in the ecosystem. Then again, one or two dissertations were defended on them, and one graduate student even described a new species. It turned out to be a deformed specimen, but everyone only found out about that after he got his degree. Nature overfulfilled the plan too. Back then the alga Rhizosolenia managed to take hold in the Caspian. Not that there wasn't a native one. There was, but it was sort of small and there wasn't much of it at all. Rhizosolenia bird's claw is another matter. Sounds great! And how picturesque its thin, long, practically glass cells look underwater! A diamond snowfall. However, this same feature effectively protects it from being eaten by enemies. This is called a food dead end. Mnemiopsis and Beroe are the same kind of dead ends, as are two species of Balanus and the polychaete Ficopomatus, which moved into the Caspian between 1955 and 1960. By that time, less than ten years had passed since the opening of the Volga-Don Canal. It's now that hundreds of millions of tonnes of their valves, shells, tubes and bodies are added to the Caspian's sediment layer every year, whereas before they used to become delicacy fish on our table.

In 1958, the first crab in 2 million years was recorded in the Caspian. In the literature it is often called the Dutch crab. But it arrived at the shores of Europe on the hulls of ships from the coastal areas of the USA. The little crab likes to travel. It is able to live in very salty water and in quite fresh water. But in American rivers lives its freshwater double, which at one time was even a hit among American aquarists. This feature is a birth certificate for the double crabs, as well as for Mnemiopsis, in one of the salt-forming basins of the Gulf of Mexico. And so organisms that survived in conditions close to a nuclear winter arrived in the Caspian seriously and for a long time.

Rough calculations show that at the end of the 1980s the ten-legged Yankee consumed a fifth of the production of the benthic ecosystem of the Northern Caspian. Previously, up to 500 thousand tonnes of sturgeon fed on it. Roughly the same amount (576 thousand t) was caught in the Caspian in 1914. Even in the worst of times, the USSR and Iran got 3 thousand tonnes of black caviar. If you value the black gold at 500 "presidents" per kilogram, then a minimum of 1.5 billion USD a year is not a bad price for granting a Caspian residence permit to a former US citizen.

In 1994, the sturgeon catch by the Caspian states (excluding Turkmenistan) was about 8 thousand t. In 1995, only 3.1 thousand t were caught, and the forecasts of TRAFFIC experts about an annual decline in Caspian sturgeon catches of 1-1.5 thousand tonnes seem to be coming true. In 1997, the value of the sturgeon and caviar harvested in the Caspian each year was estimated by M.O. Tolboev and G.M. Abdurakhmanov at 5.6 billion US dollars. Seals brought in 22.3 million, and kilka was worth only 0.3 million dollars. Thus, about 6 billion dollars a year is what the Caspian states will pay for the appearance of yet another overseas visitor in their waters. Freshwater fish in the mouths of the rivers of the Caspian basin are worth about 32 million dollars and may also join the sorrowful list.

However, there are other losses that cannot be valued in any currency in the World. The loss of biological diversity. This is so priceless that the disappearance of an endemic shell, Andrusov's Dreissena, which lived in the Northern Caspian until 1961, went completely unnoticed at KaspNIIRKh. It took the crab just 4 years to do this. Besides that, it wiped out dozens of other snail species, the overwhelming majority of which have not been studied even from a zoological point of view.

A story with zoology

The ease with which the immigrants dealt with the Caspian natives in the colonial war inspired Soviet scientists with ideas of reconstructing the fauna of an entire sea basin. This was explained in keeping with the revolutionary spirit of those years. The Caspian fauna, so the story went, was ancient and opportunistic, while the Mediterranean fauna was young and progressive. It did not matter that these grandiose phrases had no scientific confirmation. There was simply nowhere for it to come from. In 1937 the great Russian oceanologist N.M. Knipovich wrote: "at present we do not yet fully know even the entire composition of the fauna and flora of the Caspian Sea; we do not yet know precisely the annual course of changes in the composition of the animal and plant plankton and benthos, at least in all the main parts of the Caspian; we do not have detailed long-term data on the hydrological and biological conditions in the main parts of this body of water, and in the absence of such data we often find it impossible to understand the causes of the sometimes sharp changes in the abundance of particular elements of the flora and fauna." I put my signature under these words in 2000. I hope that our descendants will say the same. But the progressive Soviet scientists needed only a few years not only to justify, but also to transport into the Caspian the Abra shell and the polychaete worm Nereis. The latter was found in 1944. It was a nationwide joy, comparable to the jubilation over victories on the fronts of a bloody war. By 1952, dozens of articles and a collective monograph had been written about this event. And, as was the custom, several criminal cases had been opened as well. However, the employees of the grey blocks of Leningrad, Moscow and other cities apparently could not find any deliberate sabotage, and the Soviet government had to fork out for several prizes and the title of academician.

In 1960 an American, Olga Hartman, sent the academician a letter, or rather a scientific paper, which showed that the species of worm living in the Caspian was not the one Soviet zoologists had written about. It is frightening to think what might have happened if the same thing had been discovered by a Soviet graduate student or even a researcher with a degree. Even now such discoveries are not without danger. Or if the greatest scientist of all times and peoples had read the letter in the Zoological Journal. This story became the most hushed-up page of zoology. And not only Caspian zoology. Two circumstances are consoling. Olga was our compatriot. And she spent her millionaire husband's money on educating not only our academicians.

A venomous visitor

Unenlightened Caspian fishermen noticed during "sea" fishing that when they worked with nets that had Nereis on them, their hands turned red and swelled. Out of ignorance they attributed this to the worm's bites. Which is certainly wrong. It could have been caused by pricks from the stiff hollow bristles that serve as the polychaetes' defensive organs. According to foreign medical data, almost all known cases of poisoning by them occurred in seas of the subtropical and tropical zones. Our Aesculapians simply kept no such statistics. After all, who doesn't know about fishermen's and hunters' tall tales? Japanese chemists working on the problems of their fishermen and farmers first isolated and then synthesized the insecticide nereistoxin. I think the name needs no comment. There is no need to prove that the exotic worm was brought to the Caspian not for fun, but as food for commercial fish. They ate it, eat it, and will keep eating it — there is hardly anything else left. In 1968 a most interesting book by the toxicologist N.S. Stroganov was published. Studying the feeding of sturgeons under experimental conditions, he found that the juveniles refused 2 out of 7 types of food (Nereis, and frog meat and skin). This is explained by their toxicity. Sturgeon fry fed on tadpoles did not grow.

At the end of the 1980s, 100% of the Russian sturgeon, 70% of the stellate sturgeon and 30% of the beluga entering the Volga to spawn suffered from muscle tissue stratification, or myopathy. Perhaps it is a coincidence, but Russian sturgeon consume more Nereis than stellate sturgeon, while beluga hardly feed on it at all. V.I. Lukyanenko determined that the cause of the disease was cumulative polytoxicosis. It's not that this fish can't be eaten, but it's unpleasant. That is why one of the instructional letters of the CPSU Central Committee proposed distributing products from diseased sturgeon through the retail network outside the special distribution outlets. But diseased eggs dissolve into a uniform black mass not only on a sandwich, but also on spawning substrates. It is assumed that the main cause of the sturgeon disease is their accumulation of heavy metals and pesticides. In days long gone I was looking, for an Astrakhan commission, for data on the maximum permissible content of mercury, which the West Germans had found in a batch of canned goods from one of the fish processing plants. I found it. But only for soils. In them, there was supposed to be less of the silvery metal than was present in the exported food product. Now, when they send us poisonous sausage, we are rightly indignant, yet we export fish like that to them. We ourselves sometimes allow ourselves to accumulate base metals too, but we don't set off the alarms at airport security yet. And maybe we never will, since pesticides and other organic poisons are detected by other methods.

No study of the toxicity of the species acclimatized in the Caspian has ever been carried out, and the question was not raised when the causes of myopathy in sturgeon were being investigated either. Yu.I. Altufyev, who specifically worked on finding out why the tissues were stratifying, kindly informed me that he knows of no histological studies of the sturgeon digestive tract. So perhaps, while we are studying the malicious Mnemiopsis, we could take a look at the other invasive species as well? Because the way things usually go, if someone turns up uninvited, he's harmful, and if we brought him in ourselves, he's good. But the worm that took hold in the Caspian was not the one whose introduction was "scientifically" justified, but a completely different one. Back when it was fashionable to write about the positive role of introduced species, A.K. Saenkova and B.M. Epshtein wrote about Nereis progressively displacing Caspian organisms. Later the same was established for the "scientifically" justified mollusc Abra.

The Caspian we have lost

As is customary, let's start from the good old baseline of 1913. Back then, as now, 95% of the world's sturgeon were caught here. Although back then it was almost 500 times more. In 1914 the Caspian yielded half of the 1,168 thousand tonnes of fish caught in the Russian Empire. At that time the Caspian had no predators like Mnemiopsis, the crab and Nereis. Or rather, the predators were the seal and the valuable commercial species of sturgeon, salmon and herring. There were so many large herring coming up the Volga to spawn that they were rendered down for oil for technical purposes. The herring and sprat fattened up on crustaceans that developed in the cold upwelling waters of the Middle Caspian. The salmon, beluga and seal fed mainly on sprat, which in those years interested hardly anyone but zoologists. Sturgeon and stellate sturgeon fed mostly on small bottom-dwelling animals concentrated in the top layer of the sediment. An amazing feature of the Caspian "marine" ecosystem was that its biomass increased in winter, while that of the freshwater biosystems at the river mouths increased in summer. They were sustained by a constant inflow of nutrients brought into the Caspian by the Volga, dozens of other rivers and hundreds of streams. This provided healthy year-round feeding for the commercial fish, crayfish and the seal. Short food chains converted biological matter into delicacy seafood and valuable furs with high efficiency. Back then the Caspian was one of the most productive bodies of water in the world. To its misfortune, it had a poor flora and fauna, which made it tempting to improve everything. Then again, the Aral in those years was even poorer in aquatic life, yet it beat the Caspian in fish production per hectare.

After the Great Stalin Plan for the reconstruction of the Volga and less great construction projects on other rivers were carried out, nutrients began to accumulate in the reservoir basins, causing the growth of toxic blue-green algae. But even in the early 1950s, 80% of Caspian catches were sturgeon and salmon, and the shelves of fish shops in Astrakhan were piled high with blue tins of black caviar and golden sturgeon tesha. In the 1980s, after the successful reconstruction of the Caspian fauna, the proportion flipped and sprat came to make up 80% of the catch.

The introduced food species behave towards the fish roughly the way mullet behave towards our anglers. Only they hide not in warm Iranian waters but deep in the sediment. Abra goes down 15 cm, Nereis 25, and the crab as much as half a metre. Even crucian carp couldn't reach them at such depths if it lived in the Caspian. Never mind sturgeon. Maybe that's why the biomass of food organisms in the Caspian kept growing while the catches kept falling? Naturally, the reasons include the damming of rivers by hydroelectric plants and irrational fishing, fluctuations in sea level and pollution. But the oil and chemical industries of Azerbaijan and Turkmenistan "managed" to kill off only the Bay of Baku, the coastal waters near Sumqayıt and Soymonov Bay in Krasnovodsk Bay, and to undermine the productivity of the areas adjacent to them. The introduced species, long before Mnemiopsis, had almost completely changed the face of the Caspian at depths down to 100 m.

Just two years ago Russian fishermen took about 164 thousand tonnes of fish from the Caspian, 42% of it small sprat. In 1998 the catches of Turkmenistan were almost 100% sprat, and those of Azerbaijan 75%. In a few years the sprat will disappear too.

Nobody's to blame? But what is to be done?

There's no counting on success in saving the Caspian fishing industry, but there's no harm in trying. The attempt will serve a social and psychological purpose more than it will produce any real result.

If the Caspian states do try to save the Caspian after all, it would be better to acclimatize northern Beroe from the White Sea or the North Atlantic there. This should be done not from natural populations but from laboratory cultures. Otherwise, new undesirable and dangerous visitors or their parasites could be brought in. For acclimatizing northern species, the anomalously cold upwelling waters off the coasts of Kazakhstan and Turkmenistan can be used. Warmth-loving Mediterranean animals have only one chance of not dying: the warm and salty Krasnovodsk Bay in Turkmenistan. Releasing them anywhere else would be like throwing banknotes into the sea. This will not solve the problem completely, but it may cut the rate at which Mnemiopsis develops by half. Before starting the practical part of the operation, everything must be weighed many times over, since a new huge mouth could turn into new Caspian-wide disasters. An open competition of projects for this kind of work could be held. Mnemiopsis is studied not only abroad but also at the Institute of Oceanology of the Russian Academy of Sciences, where the research is conducted by M.E. Vinogradov and his staff. Under no circumstances should this work be entrusted to KaspNIIRKh, whose director demonstrates complete ignorance of elementary matters. He was not even able to draw the attention of oceanologists from Russia, Ukraine, the USA and the EU to this problem in time. This should have been done a year ago, when he had underwater video footage of the invader at his disposal. There was never any hope that Mnemiopsis would not survive in the Caspian. The anomalously warm winter only helped the comb jelly outpace all its predecessors in the rate of spread by a year.

Secondly, biological collections need to be gathered and concentrated at the Zoological Museum of Moscow State University, the Zoological Institute of the Russian Academy of Sciences and similar centers in the CIS. It would also be good to create genetic databanks of Caspian organisms.

Thirdly, Russia needs to repurpose some of the fish hatcheries in Astrakhan Oblast to stock the numerous ilmens of the Volga delta with juvenile Caspian sturgeon. The reservoirs of the Volga and Don basins can be restocked with juvenile sterlet. This will help at least partly offset the rise in unemployment in the fishing industry and the coming economic losses.

To avoid new disasters, all paddlefish must be removed from the Volga delta and other places to water bodies in closed-drainage areas, for example Kalmykia. In addition, a law of the Russian Federation must be adopted prohibiting any acclimatizations in the future, and the Caspian states should be invited to sign a similar intergovernmental agreement. Finally, state control must be organized over vessels heading into the Volga basin and the Azov and Baltic seas.

If our forecast for the development of comb jellies in the Caspian comes true, just as it did for the invasion of Mnemiopsis, then in the future the Caspian will be of interest only as a source of hydrocarbons. Probably Russia's environmental policy in the Caspian should already take into account the realities of the fishing industry. Perhaps the development of promising oil and gas fields in the Russian sector of the Caspian will give work to former employees of the fishing industry of Astrakhan Oblast, Dagestan and Kalmykia. We already have the only man-made desert in Europe; now there will be a dead sea.

Anatoly Tarasov, Candidate of Biological Sciences, Moscow