Department of fauna ecology

Historical note of the scientific department of fauna ecology

According to the Charter of the state environmental research institution "Polesie State Radiation and Ecological Reserve" and the Law "On the Legal Regime of Territories Subjected to Radioactive Contamination as a result of the Chernobyl accident," the main functional purpose of the Polesie State Radiation and Ecological Reserve is the preservation of natural complexes in their natural state. This is also in line with the provision of the 2002 UN report “Humanitarian consequences of the Chernobyl accident. Rehabilitation strategy ”, proposing to use the potential of the Chernobyl territories for the countries affected by the Chernobyl disaster to fulfill international obligations to preserve biodiversity.

In the first decades after the Chernobyl disaster, the main emphasis of the ongoing scientific work of the Polesie State Radiation-Ecological Reserve was placed on the most relevant radiobiological research during this period. However, the work carried out in the country to study the animal world indicated the high potential of the Polesie State Radiation-Ecological Reserve in preserving the biodiversity of the fauna.

In 1998, the department of animal radioecology in the reserve began to study the dynamics of accumulation and the peculiarities of the development of faunistic complexes in the radioactively contaminated territory.

In 1998–2000, research work was carried out on the topic "To develop scientific principles for the preservation and development of natural complexes of the Polesie State Radiation-Ecological Reserve." Under the leadership of Ph.D. T.M. Odintsova and Ph.D. Kiriyenko, census of the number of wild animals was carried out, an assessment of the state of the avifauna, micro- and macroteriofauna and their helminthic complexes was given; the state and number of populations of ungulates and predators has been determined; the features of the formation of the "parasite-host" system in the absence of anthropogenic influence have been established; the dynamics of accumulation of radioactive cesium by various systematic groups of wild animals has been studied.

As a separate structural unit in the scientific part of the reserve, the scientific department of fauna ecology was established on July 4, 2001. During 2001-2005, the work was carried out in the direction "Study of the structural-functional state and dynamics of natural complexes in the conditions of the Polesie State Radiation-Ecological Reserve". Under the leadership of Ph.D. T.M. Odintsova and Ph.D. S.V. In Kuchmel, the accumulation of 137Cs in mammals of various trophic levels was monitored; analyzed the dynamics of the specific activity of 137Cs in organs and tissues of game animals, its distribution in the gastrointestinal tract and reproductive organs, as well as the content of 137Cs in organs and tissues of rodents and insectivores. Leading researcher of the scientific department of fauna ecology, Ph.D. T.G. Deryabina conducted studies of the biotopic distribution and sex and age structure of wild ungulates and monitored the state of mammalian populations included in the Red Book of the Republic of Belarus. The employees of the department carried out work on the study of biocenotic relations of predators of the family. Canids, studied the structure of food and the assessment of the impact of the wolf on wild ungulates, the structure of food of the fox and raccoon dog; conducted a comparative analysis of the trophic relationships of carnivorous mammals using the example of a wolf, a raccoon dog and a fox.

Research and development work in 2006–2010 was carried out on the topic “Assessment of the significance of the Polesie State Radiation and Environmental Reserve in maintaining and preserving the biodiversity of vertebrates in the Polesie region and Belarus”. Under the leadership of Ph.D. S.V. Kuchmel and with the participation of Ph.D. T.G. Deryabina studied the species richness of terrestrial vertebrates, their species composition and spatial distribution; determined the indicators of the structure of the population and reproduction of mammals; the morphophysiological characteristics of the species in the radiation biogeocenosis and the intraspecific diversity of terrestrial vertebrates are given; the levels of radionuclide content in vertebrates of various systematic groups have been established. Scientifically grounded proposals were prepared to optimize the protection of rare species of vertebrates in the PSRER.

Leading researcher, Ph.D. V.A. Penkevich conducted research on the helminthological state of the population of wild ungulates and predatory animals of the reserve. Researchers O.A. Pareiko and V.V. Yurko determined the significance of the PSRER area for waterbirds in Europe.

In 2011–2015 scientific research was carried out in two directions. Under the leadership of Ph.D. S.V. Kuchmel's research work was carried out on the assignment "Protected species of animals in the radiation biogeocenosis". Together with Ph.D. T.G. Deryabina studied the social, spatial structure and reproduction rates of the badger population on the territory of the Khoiniki section of the PSRER; monitoring of the territorial grouping of brown bears and groups of lynxes was carried out; the area of habitation and the number of reproductive groups of the Przewalski horse have been established; the habitats of hazel dormouse and dormouse were established. Senior Researcher V.V. Yurko determined the species composition of birds protected at the national and international levels inhabiting the territory of the PSRER. Senior Researcher V.N. Lukashevich identified and mapped the main reproductive stations of the marsh turtle; gave the morphometric characteristics of the species in the absence of anthropogenic pressure; established the indicators of reproduction of the European marsh turtle on the territory of the reserve.

Under the guidance of a leading researcher, Ph.D. V.A. Penkevich's research work was carried out on the assignment "Parasitological assessment of biotopes of wild ungulates for the most dangerous helminthiasis and trichinosis in the main biotopes of the reserve." A parasitological assessment of the main biotopes of wild ungulates is given; infestation of earthworms with metastrongylid larvae in the main wild boar biotopes was established; the infestation of mollusks by larvae of trematodes in the water bodies of the main ungulates of the reserve was studied; the epizootic situation of trichinosis among wild carnivores and wild boars was assessed.

The results obtained were an integral part of the assessment of the state of populations of rare animal species in the PSRERZ and the significance of its territory for the conservation of biodiversity of the animal world.

In 2016–2020. work is carried out on the assignment "Terrestrial and aquatic biocenoses of the reserve for the preservation of biodiversity of fauna and the peculiarities of the circulation of zoonotic helminthiases." Under the guidance of Doctor of Biological Sciences, Professor L.S. Tsvirko established the species composition, number and features of the spatial distribution of ixodid ticks, as well as the infection of ixodid ticks with pathogens of viral and bacterial nature. Leading Researcher, Ph.D. V.Ch. Dombrowski studied the species composition, age and sex structure and relative abundance of bats in different types of habitats of the reserve. Senior Researcher V.V. Yurko determined the species composition and number of birds of the coastal water complex. Senior Researcher V.N. Lukashevich established the species structure of the green frog complex and its ratio in water bodies of various types. Senior Researcher D.N. Ivantsov studies the accumulation of radionuclides in fish of various trophic status. Head of the department I.S. Yurchenko together with the 1st category specialist D.O. Shatilo and junior researcher N.G. Nadina is conducting research on the parasite fauna of terrestrial and aquatic animals.

The main areas of research of the Department of Ecology of Fauna are:
    • studying the biodiversity of terrestrial and aquatic invertebrates and vertebrates;
    • control of the epizootic and epidemic situation for parasitic infections and invasions of animals;
    • study of the state of animal populations in conditions of radioactive contamination of the environment;
    • monitoring the content of radionuclides in organs and tissues of wild animals.

Of the terrestrial vertebrates included in the Red Book of the Republic of Belarus, 11 species of mammals, 59 species of birds, two species of reptiles and one of amphibians have been established on the territory of the Polesie State Radiation-Ecological Reserve. Many of them are included in the Red List of the International Union for Conservation of Nature and in the Appendices of the Bonn Convention, and all are protected by the Berne Convention.

The contribution of the Polesie State Radiation-Ecological Reserve to the strategic successes achieved by Belarus in the conservation of bison is evident. The territory of the reserve is inhabited by one of 9 free-living populations created in the republic and characterized by high reproduction rates. For 2020, its number was 174 individuals. With an increase in the number of animals, changes took place in the social structure of the population. The number of social groups has grown to 25. The existing age and sex structure of the population is characterized by the following indicators: adults - 78.2% (of which the share of adult males - 32.1%, females - 40.1%), young animals - 17.0%, calves up to 1 year - 4.8%. The age and sex composition of the Polissya bison population differs from the proposed optimal age and sex structure due to the predominance of adults in the population with an insignificant number of young animals.

The bison of the Polissya population has never been subjected to selective withdrawal and the formation of its social, sex and age structure. The development of the territory of the reserve by bison occurs naturally, without human intervention. It is advisable to preserve this specific status of this population in the future in order to track the main parameters of its state (including the lifespan of individuals) in conditions of radioactive contamination of the environment, as well as to obtain materials in a comparative way with populations under human control.

The territorial groups of lynx (about 30 individuals) and badger (about 120 individuals) are among the largest even among those living in specially protected natural areas of Belarus and make up about 20 and 30% of the population in the territories of national parks and reserves (about 8.5 % and 7% of the population in the republic).

The bear is a permanent inhabitant of the reserve.

At the beginning of 2020, the number of red deer was 1,989 individuals, elk - 1224, European roe - 704, wild boar - 320, wolf - 122 individuals. 

Based on the study of various aspects of wolf biology on the territory of the reserve, preliminary conclusions can be drawn that the flocks permanently living in the exclusion zone do not go beyond the boundaries of the reserve to hunt and search for food. At present, in the conditions of a sharp decline in the number of wild boars, the main food item for wolves in the reserve in winter is the elk due to its high number. There is a seasonal difference in hunting activity. The maximum number of caught large ungulates was recorded in November-December, the minimum - in May. It should be noted that, despite the predatory load of the wolf, the elk population in the reserve has a positive dynamics of numbers in recent years.

In recent decades, a decline in the number and a limitation of the territory of distribution of mammals of the Sonya family has been observed everywhere, which is explained by the actions of an anthropogenic factor. This led to the inclusion of hazel dormouse and dormouse dormouse in the IUCN Red List and in the Red Book of the Republic of Belarus. On the territory of PSRER, 10 permanent habitats of the dormouse were identified. 24 places have been identified where hazel dormouse is regularly recorded.

Since 2007, Przewalski's horses have been living in the reserve. They independently entered from the Ukrainian Exclusion Zone of the Chernobyl nuclear power plant, where they were brought in 1998-1999 from the Askania-Nova reserve and the Lazovsky stud farm in order to create a free population of Przhevalsky horses in the exclusion zone and resettlement zone of the Chernobyl nuclear power plant. Przewalski's horse is an invasive (alien) species for the territory of Belarus and at the same time it is a species of high international environmental significance: it is listed in the Red Data Books of the Russian Federation and Ukraine, in the Red List of the International Union for Conservation of Nature. Przewalski's horse is an endemic of the fauna of Central Asia, an inhabitant of steppes and semi-deserts, the last surviving species from the group of Pleistocene wild horses that inhabited the steppe expanses of Eurasia and North America. Already at the time of its discovery (1879), Przewalski's horse was not numerous and inhabited the remote areas of the Dzungarian Gobi, and since the 70s of the 20th century it has ceased to be found in nature. The species has survived only thanks to breeding in zoos and reserves. Since 1992, work has been carried out to return the species to nature, natural populations have been created in Mongolia, China, Kazakhstan. An experiment has begun in Russia on the reintroduction of Przewalski's horses into the Orenburg steppes.

In the reserve, the habitat of the Przewalski horse mainly covers the Narovlya section of the reserve. Their places of residence are associated with the presence of open spaces in the form of former farmland overgrown with herbaceous vegetation in the area of evicted villages and steppe grass meadows in the floodplain of the Pripyat and its tributaries. Former settlements and their surroundings are actively used by horses as places for daytime rest and grazing. Horses prefer to arrange daytime parking in empty stone buildings - cowsheds, pig farms, warehouses, hangars for agricultural machines.

In 2018, there was a sharp increase in the migration activity of horses and the transition of some herds (about 20 individuals, including several foals) to the left bank of the Pripyat (Khoiniki district). In total, 5 reproductive herds were observed, as well as a group of stallions of 4 individuals, single individuals. Regular transitions of individual groups to the territory of Ukraine and back were noted. In the period 2016-2018. at least 14 foals were born. The number of horses in the reserve in the fall of 2018 was about 50 individuals. In the spring of 2019, it again decreased to 20-30 individuals, apparently due to the return migration of a part of herds to the territory of Ukraine. The main part of the reproductive herd, which crossed over to the Khoiniki side in 2018, settled in the area of the bnp Borshchevka and Masana. During the winter of 2018/2019 and the spring of 2019, horses were regularly sighted in these former settlements.

The absence of people, the protected regime of the territory, the presence of fallow lands with secondary steppe vegetation, cereal and field meadows in the Pripyat valley and its tributaries, climatic conditions have a favorable effect on the state of the emerging free group of Przewalski's horses - animals in all seasons are in good physical condition and successfully reproduce.

The consequences of any invasion of alien species, including an independent one, as happened with the Przewalski's horse on the territory of PSRER, are still unpredictable. For invasive species in new conditions often change themselves: animals - change their behavior, preferred food, plants - the nature of growth. The development of the Przhevalsky horse on the territory of the PSRER, undoubtedly, requires monitoring this process from different angles: the impact on the state of populations of native species, the study of the adaptive capabilities of an alien species.

In 2016, employees of the Department of Ecology of Fauna began researching representatives of the order Bats, the least studied order of mammals. The studies obtained as a result of the analysis of sonograms and the capture of bats with spider nets have established that the species composition of bats in the reserve includes 12 species, 4 of which are included in the Red Book of the Republic of Belarus.

Of the 232 bird species in the reserve, 190 migratory (81.9%) and 42 sedentary species (18.1%) were recorded, of which 172 species nest. The annual registration of several new species for the reserve shows that the study of the avifauna remains far from complete. Potentially, it is possible to register about 250 species of birds recorded in the Polesie territory in the reserve.

The territory of the reserve supports globally and critically endangered species, as well as vulnerable bird species. Of the birds listed in the Red Book of the Republic of Belarus, 39 species nest and 4 species presumably nest, 15 were recorded during migrations and one species - in winter. Among them, 9 species are under the global threat of extinction (81.8% of the species composition of this category in Belarus), 14 species are under critical threat of extinction (93.3%).

More than 50% of the protected species from the taxa represented in the region are represented on the territory of the reserve. Among the species protected at the international level, on the territory of the reserve, like nowhere else in Belarus, there is a high number of white-tailed eagle - a species that is under the strict protection of the IUCN Red List. 10-15 pairs nest here, and the total number of the species is about 100 individuals.

The number of the Great Spotted Eagle, which is globally threatened with extinction in Europe, is at least 16 pairs and there is a tendency to further increase in its number. At the present time, two rare species live together on the territory of the station - the Greater and Lesser Spotted Eagles. In many regions of the country, these species enter into hybridization and produce fertile offspring. The frequency of occurrence of hybrids in a population usually reflects the degree of anthropogenic transformation of natural biotopes and can be used as a bioindicator of the state of the environment.

Corncrake (strictly protected by the IUCN Red List, a vulnerable species in Europe) in the reserve is a common, in some years numerous, nesting species. The abundance of the great bittern is high - more than 50 breeding pairs, the black stork - 20-30 pairs, the lesser spotted eagle - more than 20 pairs, the small rat - more than 100 pairs, the common crane - 30-50 pairs, over 50 pairs of the little tern ( terna albifrons), golden bee-eater (Merops apiaster) and common kingfisher (Alcedo atthis). Of the rare passerine birds, more than 100 pairs of white collar flycatcher and garden bunting (Emberiza hortulana) nest. A high number of other rare species.

All this testifies to the importance of the reserve for the conservation of endangered species, which corresponds to the second criterion of the Ramsar Convention.

Thus, the current situation in the reserve contributes to the preservation of common and rare bird species, including those endangered. In terms of the species composition and abundance of rare bird species listed in the Red Data Books of the IUCN and the Republic of Belarus, the territory of the reserve meets criterion 2 of Ramsar sites. According to the number of migrating and nesting waterfowl, it is a potential Ramsar site according to criteria 5 and 6.

Of the 13 species of amphibians of the fauna of Belarus, 11 live in the reserve, and all of the 7 species of reptiles are noted. Here is concentrated the largest population of a rare species in Belarus and one of the largest in Europe - the European marsh turtle, one of the most unique species in the fauna of the republic, an exclusive representative of the Turtle order, the oldest and the longest living vertebrate animal, numbering about 70 thousand individuals.

To date, the marsh turtle in Belarus, as well as in most of the shrinking habitat, is rare. As a result of anthropogenic press, the species is included in all three editions of the National Red List, IUCN Red List, Appendix II of the Berne Convention. The species is included in the Red Data Books of Lithuania and Latvia. In Russia, the marsh turtle is included in the "List of objects of the animal world in need of special attention" (Red Data Book of Russia: legal aspects, 2000) and a number of regional Red Data Books. In Ukraine it is included in the Red Data Books of Kiev, Sumy and Kharkov regions. Poland even adopted a special state program "Active protection of the marsh turtle in Poland". Of the surviving territorial groupings of the species in Western and Central Europe, many are isolated and have low viability. Studies of the DNA of marsh turtles from Poland and Germany have revealed very poor genetic variability at the level of island populations and zoos.

On the territory of PSRER, characterized by the absence of man and his economic activity for more than a quarter of a century, the turtle feels more than at ease. Having survived in hard-to-reach “wild” corners, by now it has spread widely throughout the entire territory of the reserve, including many reservoirs of anthropogenic origin - reclamation canals, floods, water-filled sand pits and reservoirs in road ditches.

Another rare species of reptiles, the copperhead, is constantly recorded.

To date, 33 species of fish belonging to 8 families have been registered on the territory of the reserve.

The family of Karpovs is most fully represented in the catches - 21 species. Five species are represented by the Okunev family, three by the Bychkovy family, and one each by representatives of the Shchukov, Somov, Vyunov and Treskov families.

For the Pripyat River, the dominant species was roach, and the subdominant species were blue bream and silver bream. In the lakes located in the Pripyat floodplain, the dominant species are roach and bream, and blue bream and silver bream are subdominant species. On the small river Nesvich and canals of the reclamation network, the dominant species is the goldfish, and the subdominant is the pike.

The levels of 137Cs content in fish in different water bodies differ significantly from each other, which is associated, first of all, with the levels of radioactive contamination of adjacent territories. The highest values of the specific activity of 137Cs in fish are characteristic of the system of amelioration network and closed reservoirs located in the floodplain of the Pripyat River, slightly lower values are noted for reservoirs with a higher level of flow - Lake Semenitsa, and minimum - for the Pripyat River.

Parasitic diseases are one of the main factors affecting the number of wild animals. Many types of helminths cause serious diseases, which, when exposed to unfavorable factors, can lead to death.

According to the results of helminthological autopsies and coproscopy (2006-2010), 43 types of helminths were identified in wild ungulates (bison, elk, deer, roe deer, wild boar) on the territory of PSRERZ, and 25 in carnivores (wolf, raccoon dog, badger). for Belarus Ph.D. V.A. Penkevich discovered the trematode Metagonimus yokagawai (Katsurada, 1912) found in a wolf caught on February 06, 2005. In addition, for the first time in the republic, the wolf is indicated as the definitive host of the nematode Dirofilaria immitis ( Leidy, 1856). Helminthic invasion remained stably high throughout the entire study period (the extent of invasion of wild ungulate mammals was 41.3–100%, predators - 84.4–100%) and did not differ from the invasion of mammals in specially protected natural areas.

In the parasitocenosis of carnivorous mammals (raccoon dog, American mink and river otter), 19 species of helminths belonging to 3 types, 4 classes are currently (2016-2019). The class of trematodes is represented by 8 species, cestodes - 3, nematodes - 6 and 2 species belong to the class of acanthocephalus. The total infestation of the raccoon dog by helminths was 100%. The trematode Alaria alata occupies the leading position in the parasitocenosis of the raccoon dog; in the internal organs of some individuals its number reached 4026 specimens. The American mink is 93% infected with helminths. The dominant species is Spirometra erinacei-europei from the cestode class, the occurrence of which is 65%. Of the trematodes, the species Еchinochasmus perfoliatus is more common. It dominates in terms of the intensity of infection, like the species Pseudamphistomum truncatum.

Freshwater fish of the ecosystems of the reserve are infested by 67.0% by representatives of five classes of helminths, represented by 26 species. In quantitative terms, the fish of the reserve are dominated by trematodes (65.98%), followed by monogeneans in frequency of occurrence (5.78); the third place belongs to scrapers (2.04%), followed by cestodes (1.36%) and nematodes (0.34%).

Of the fish species studied by us, the highest diversity of helminth species was noted in tench (15 species), followed by roach (14), bream (11), crucian carp (10), 9 species of parasites were found in blue bream and asp, 7 in ide and sabrefish, 5 species of helminths were recorded in silver bream, 4 in perch and one species in catfish. 

Our studies of the parasite fauna of fish for the presence of helminthiases, which are of epidemiological significance, have established the presence of causative agents of opisthorchiasis, methorchiasis, pseudamphistomiasis and apophaliosis in water bodies. Metacercariae of the genera Metorchis Loos, 1899 have been registered; Opisthorchis Blanchard, 1895; Pseudamphistomum Lühe, 1908, belonging to the family Opisthorchiidae, Braun, 1901 and Apophallus Jagerskiold, 1898 from this family. Heterophydae, Leiper, 1909.

The presented materials indicate a stable circulation of epizootologically and epidemically important natural focal helminthiases on the territory of the Polesie State Radiation-Ecological Reserve. These include such trematodoses as opisthorchiasis, metorchiasis, pseudamphistomiasis, paragonimiasis and alariasis; cestodoses - sparganosis and diphyllobothriasis, as well as nematodosis trichinosis. This indicates the presence of a complex of biotic and abiotic factors contributing to the maintenance of natural foci of pathogens.

On the territory of the reserve, 2 species of ixodid ticks were found: Ixodes ricinus and Dermacentor reticulatus. The absolutely dominant species is Dermacentor reticulates, accounting for more than 92%.

Of the surveyed biotopes, the largest number of ticks was recorded on the territory of former settlements and on drained peat bogs. In the surveyed forest biocenoses, the largest number of ixodids was recorded in oak forests, somewhat less - in alder forests. In open biocenoses, mites were most often caught on fallows of agricultural land, their smallest number was caught in floodplain meadows.

The study of vectors of tick-borne encephalitis by the method of enzyme-linked immunosorbent assay made it possible to detect the virus antigen in Dermacentor reticulatus ticks in 63.6%, and in Ixodes ricinus - in 25.0%.

As a result of short-term studies on the territory of the reserve, the habitat of 29 out of 70 species of insects included in the Red Book of the Republic of Belarus was revealed. The habitat of two species, included in the Appendix of the Red Book, as requiring additional study and attention for the purpose of preventive protection, was established: the blue ribbon and the Humpbacked Ktyr-lyafria. Three species inhabiting the reserve are protected by the legislation of other states: steppe scolia, carpenter prion beetle and fringed leaf beetle. New species for the fauna of the Republic of Belarus have been discovered - the giant scolia, the South Russian tarantula and the praying mantis.

It should be especially noted that along with the strict conservation regime, its large area (216.4 thousand hectares) plays an important role in the high species saturation of the territory of the PSRER. It allows the existence and development of territorial groupings of species (especially large carnivorous mammals and birds) that require a large living space for organizing their social structure and providing forage lands.

Investigations of the territories of radioactive contamination show that regardless of the effect of the radiation factor, in the absence of anthropogenic impact and a strict regime of protection, the processes occurring in animal populations practically do not differ. Therefore, in areas contaminated with radionuclides, it is necessary to carry out not only radioecological, but zoological and environmental studies. Studies carried out at NOEF in 2006–2010 have shown that the population parameters of the animals of the PSRER are in line with those established in areas with a background level of pollution. This makes it possible to use this territory not only for conservation, but also for the study of the peculiarities of the biology of species for the creation and improvement of measures for their protection.

Head of the Department of Ecology of Fauna

Inna Stanislavovna Yurchenko