The population of Anser fabalis fabalis wintering in Europe have shown decline in recent decades. At the same time, the population dynamic of most migratory birds largely depends on the quality of migratory stopover sites, which are necessary to replenish internal reserves. The migration ecology of Anser fabalis fabalis wintering in Europe has not been sufficiently studied. Only in general terms we know about the timing of migration, while the places of key stopovers in Russia are not described. There is no information about conservation status of key sites and the intensity and duration of their use by Anser fabalis fabalis individuals. Without this knowledge, it is impossible to organise effective protection of any migrating population. We have analysed the dynamics and phenology of migrations, as well as the conservation status of stopover and pre-migration sites of Anser fabalis fabalis nesting in the forest zone of Western and Central Siberia and wintering in Northern Germany and Poland, based on data from GPS/GSM transmitters. We used data from 45 completed spring migrations from 25 tagged birds and 36 completed autumn migrations from 20 birds over the period 2019–2023. The migration start from wintering sites occurs in late February, on average 20 February ± 10.9 days. Arrival of the birds in the breeding areas occurs in late April, on average 01 May ± 9.4 days. Over 2019–2023, we found a trend for a shift in the dates of spring migration start (Mann-Kendall test: τ = -0.22, p < 0.05) and finish (Mann-Kendall test: τ = -0.35, p < 0.05) to earlier dates. Based on data from individual bird’s migration routes, 1031 migration stopovers with a total duration of 3529.7 days were allocated. Of these, 616 (59.8%) stopovers were located in Russia, where the birds spent 1831 (51.9%) days. Key stopovers are located in the Baltic Region, the Sviyaga-Vyatka interfluve and the centre of the River Volga Region. The start of the autumn migration occurs between 27 September and 25 October, on average 18 October ± 7.9 days. The arrival at wintering sites occurs between 15 October and 11 December, on average 8 November ± 13.4 days. Over 2019–2023, there was a trend of an increasingly later arrival on wintering sites (Mann-Kendall test: τ = 0.45, p < 0.05). The start of the autumn migration occurred also later (Mann-Kendall test: τ = 0.44, p < 0.05). Pairs with broods are characterised by a longer autumn migration (Mann-Whitney test: U = 67.0, Z = 2.58, p < 0.001), and they spend significantly more time on the pre-migration sites (Mann-Whitney test: U = 71.5, Z = 2.29, p < 0.01) and autumn stopovers (Mann-Whitney test: U = 67.5, Z = 2.56, p < 0.01). The migration speed of pairs without broods was higher than of pairs with broods (Mann-Whitney test: U = 69.0, Z = -2.5, p < 0.01). Only 15.3% of stopovers are covered by the existing network of Protected Areas, where the Anser fabalis fabalis individuals spend only 19.2% of the total time. The results of this study can be used to develop an effective strategy for the Anser fabalis fabalis conservation during the period of migrations. We propose a hunting ban and/or the creation of Protected Areas within the main key stopover sites in Russia.

The Russian Arctic supports wild sympatric ruminants and their data-deficient helminths. In this study, we: (1) collected fecal samples of wild and semiwild reindeer (Rangifer tarandus), muskoxen (Ovibos moschatus), and snow sheep (Ovis nivicola) across Palearctic North territories: Arkhangelsk Oblast (including Novaya Zemlya archipelago), Karelia and Sakha Republics, Kola, Yamal, Taimyr, and Chukotka Peninsulas, Bering, Svalbard, and Wrangel Islands; (2) conducted a coprological survey (noninvasive life-time method preferable for protected animals) to obtain eggs and larvae of helminths inhabiting digestive, respiratory, nervous, and muscular systems; (3) identified helminths according to their morphology and DNA sequences; (4) estimated parasite load per host; (5) analyzed our findings. Varestrongylus eleguneniensis (in reindeer) was reported for the Palearctic for the first time, while Orthostrongylus sp. was reported both for R. tarandus and for the Palearctic for the first time. Capillarid-type eggs were reported for snow sheep for the first time. The question of the role of wild Arctic ruminants as vectors for rotifers was raised.

Amid intensive transformations in the Arctic environment and biota, differences in population trends demonstrated by predominant and widespread Arctic herbivores are of great scientific interest. In this regard, the primary purpose of this study was to perform a comparative assessment of trophic selectivity in the barnacle goose and greater white-fronted goose in the area of their highest reproductive concentrations and estimate the role of competition in their population dynamics. The data indicate that differences in quantitative shares of plants consumed by these species are not sufficient to avoid competition and that the diet of barnacle geese is more selective (i.e., sensitive to food quality and energy consumption). However, the status of a relatively weak competitor contradicts the exponential growth of the barnacle goose population in the study area, as well as its entire Arctic population. We believe that differences in the population dynamics of barnacle goose and greater white-fronted goose are currently determined not by competition in reproductive concentration periods, but by effects exercised by anthropogenic and climatic factors far outside of their nesting range.

The sandhill crane has become a common to abundant breeding species on the tundra of northeastern Yakutia, with the ranges of both sandhill and Siberian cranes presently overlapping widely. Further range expansion of the sandhill crane to the west and a population increase could assist competition to the stenotopic Siberian crane, which is classified as a Critically Endangered species by the International Union for the Conservation of Nature (IUCN). To assess the dynamics of the Siberian and sandhill crane populations, we repeated the historical aerial surveys of 1993–1995 along the Arctic coast of Yakutia and Chukotka in 2020 and 2021. The novel methods of our survey included the use of a photo-camera in addition to a voice recorder and a GPS navigator. The survey data were processed using the QuantumGIS 3.16.5 software. The overlapping area of both crane species expanded significantly in 2020 and 2021 as compared to 1993–1995. The local densities correlate negatively: in those areas where the density of the sandhill crane increased, the density of the Siberian crane decreased or the latter disappeared. The Siberian crane disappeared from the western part of the Kolyma Lowland and the Kolyma Delta, where the peak population density of the sandhill crane has recently been reported. Our data show some concentration of the Siberian crane range in the Yana–Indigirka Lowland. The areas of the maximum density of the two species do not coincide, the distance between their centers amounting to 400 km. The center of the maximum density of the sandhill crane has shifted to the west by 400 km from the Chaun Lowland to the Kolyma Delta over 28 years, while the numbers remain almost stable. They increased 1.22 times between the aerial surveys and can be estimated at 41 930 individuals in the areas under survey. The density of the Siberian crane increased 5.3 times over the same years, the population numbering 2086 individuals in the areas surveyed.

The Taimyr Peninsula is a key region for reproduction of waterfowl of European and Asian wintering populations. The uniqueness of Taimyr is that birds migrate there from both the west and the east, following five out of eight global flyways: East Atlantic, Black Sea/Mediterranean, West Asian/East African, Central Asian, and East Asian/Australasian. The study develops the topic of conservation ornithology and sustainable use of biological resources raised at the First All-Russian Ornithological Congress by Dr. Evgeny Syroechkovsky. Russia lacks the system of state monitoring and assessment of waterfowl populations, in particular with the use of aerial survey methods. In 2019, counts of geese in the tundra zone of the Taimyr Peninsula were carried out from the board of an ultralight aircraft specially designed for aerial surveys. New data on the abundance and spatial distribution of geese were obtained. We substantiated the methodology for the survey flight routing with no transects and the use of GIS, remote sensing, and generalized additive models (GAM) for interpreting the results and extrapolating estimates of goose abundance. A database of the results of aerial surveys was compiled (http://rggsurveys.ru). According to our estimate, for the first time made by statistical modeling for the tundra zone of the Taimyr Peninsula, more than 1.5 million White-fronted geese, about 450000 Bean geese, 78400 Red-breasted geese, and 43000 Lesser White-fronted geese nest and moult on Taimyr. Comparison of these figures with modern estimates of the world populations of these species demonstrates the key role of the Taimyr Peninsula in maintaining populations of rare and economically important Anseriformes.

Migratory connections in waterfowl in the north of Western Siberia are discussed as based on ring recoveries from the database of the Bird Ringing Center of Russia, A.N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences. Altogether, 3531 recoveries from waterfowl of 29 species were used. The waterfowl in the region are characterized by exceptionally wide migratory connections, occurring in different seasons in most regions of the Old World within the Northern Hemisphere: from Iceland to the Japanese Islands and from West Africa to the Indian Subcontinent and the Yangtze River basin. The long-distance flights of birds to molting sites, the interannual change of nesting grounds and wintering regions, as well as the distribution on wintering grounds are discussed. Ten wintering regions have been allocated. The available material on the migration of waterfowl is evaluated from the viewpoint of completing the description of their seasonal distribution and its significance in the study of ecological connections of the territory of Western Siberia.

The tundra of the East Asian Arctic is inhabited by at least three flyway populations of the tundra swan: the East Asian continental migratory flyway population of C. c. bewickii; the western Pacific flyway population of C. c. bewickii, and the western (American) flyway population of C. c. columbianus. The main objective of the present paper is to assess population trends by comparing information on the historical bird aerial survey in 1993–1995 (the only one conducted in the tundra of northeastern Asia) with the data of our aerial survey held in 2020–2021. Another aim was to estimate the proportion of breeding birds in different flyway populations. The size of the zone of intergradation of C. c. bewickii and C. c. columbianus in Chukotka and the level of hybridization have so far remained poorly studied; this issue requires clarification. The aerial survey data for 2020–2021 were processed using the QuantumGIS 9.16.5 software. The system included the following layers: a vector layer of the world map; routes of aerial surveys for 2020 and 2021; and polygons of counts for 1993–1995. The system made it possible to calculate the length of the survey. Estimates for each region were calculated for the extrapolation area given in the historical survey. Between 1993–1995 and 2020–2021, an increase in the numbers of all three flyway populations of the tundra swan was revealed on the breeding grounds. The East Asian continental flyway population increased 3.86 times versus 3.05 times for the West Pacific flyway population (while the documented growth of this population was 2.1 times, according to mid-winter counts over the same period). The Western (American) flyway population grew 2.5 times. We believe that the northern border of the summer range of the tundra swan has significantly shifted to the north, following the summer climate change and the northward shift of the subarctic tundra zone. Registration of nests and broods in areas where only nonbreeding birds were recorded during the historical survey is additional evidence of a northward displacement of the range. The Kym’’yneiveem River (about 175.6° W) borders the areas of dominance of C. c. bewickii and C. c. columbianus. A switch in dominance has been triggered, as there is no zone where both subspecies would occur in equal proportions. The overlapping area of both subspecies extends for 600 km along the Arctic coast.

In the 20th century, the breeding grounds of the barnacle goose over the territory of Russia included only the Novaya Zemlya Archipelago and Vaygach Island. Until the middle of the century, the population did not exceed 20 000–30 000 individuals. In the 1970s–1980s, the population of the barnacle goose started increasing slowly. Shortly thereafter new colonies appeared in the coastal areas of the Barents Sea, ranging from the Kanin Peninsula to Khaypudyrskaya Bay and Kolguev Island. By 2017, the population numbers had reached about 1.2 million individuals. The increase in the barnacle goose population has coincided with the phase of a pronounced temperature increase and general climate change in the Arctic. The mean annual temperatures have increased significantly in the Eastern European tundra. A simultaneous ice cover decline in the Barents Sea has led to spreading of the warm Atlantic waters much further to the east and thus rendering a heating effect extending as far as the Kara Sea. One of the consequences is a steady decrease in weather differences between the western and eastern parts of the region. The climate in the eastern part, in Vaygach Island and the Yugor Peninsula in particular, has become milder and changes relatively faster than in the western part of the region. This is believed to be one of the reasons for the vast expansion of the barnacle goose to the east and to Kolguev Island. In the spring period, in May and June, the average daily temperatures in the Eastern European tundra have not changed significantly over the past 35 years, but taking into account the lack of a pronounced temperature increase, the transition of the mean daily temperature over 0°C has shifted to a much earlier period. On the territory of the Eastern European tundra, the cumulative temperature of the summer period has increased along with the duration of the period with positive temperatures. These factors combined have led to a prolonged vegetation period and have enhanced phytomass growth. This trend is most pronounced in the post-hatching period, i.e., in July and August. The prolongation of the active vegetation period offers young barnacle geese additional advantages in one of the most crucial periods of their life, i.e., the fledging period. Adult birds have an additional opportunity to accumulate internal reserves before the autumn migration. Apparently, all these factors combined seem to have allowed for new habitats on marshes and in the typical plain tundra to be used by barnacle geese, leading to a significant increase in the numbers of the species. More detailed information obtained now fails to support the hypothesis stipulating the adverse impact of a phenological mismatch on the barnacle goose. The species continues demonstrating steady population growth. According to our estimations, there are 1 069 107 ± 37 655 barnacle geese in the Russian part of its range (excluding the Novaya Zemlya Archipelago).

A total of 702 recoveries of Bean Geese ringed on the wintering sites in the Netherlands since the 1960's have been analysed. For most of the ringed birds in this analysis the subspecies Anser fabalis fabalis or A. f. rossicus was identified at the time of ringing. The majority of recoveries are from the territory of the ex-USSR, primarily the Russian Federation. We have tested the hypothesis that hunting pressure is higher on Taiga Bean Geese, the subspecies A. f fabalis, compared to Tundra Bean Geese, the subspecies A. f rossicus. This has been checked by comparing the lifespan of the two subspecies and analysing the seasonal distribution of ring recoveries. On average, the lifespans of A. f fabalis are shorter compared to A. f rossicus, and there is a shift in the hunting periods towards spring. The reported drastic decrease in the numbers ofA.ffabalis wintering in the Netherlands could be caused by a possible change in Bean Goose wintering regions (the Eastern-European wintering sites becoming more important), but also by an overall decline in the numbers of this subspecies. According to the current analysis ofring recoveries from harvested birds, Taiga Bean Geese live on average shorter than Tundra Bean Geese do, apparently because the former are exposed to a higher hunting pressure. The Taiga Bean Goose subspecies is most vulnerable in western Siberia during the spring hunting season and, during the autumn hunting season, in the central parts of European Russia, starting from the Urals. This points to the need for additional protection measures in key seasonal staging areas and in all breeding areas, as well as for the need for a regional approach including both subspecies into the Red Data Books. Moreover, it is important to change the time of opening the spring hunting on waterfowl. Additional studies are required to more accurately determine the flyways, as well as the winter distributions of Anseriformes. This is primarily important to test the hypothesis whether there is a change in the wintering grounds of Bean Geese nesting in the Russian Federation.

Both Yamal-Belyi and Gydan populations of the wild reindeer (Rangifer tarandus) are endangered, with no exact reasons for that to be seen. In this puzzle it is very important to analyze the reindeer diet on the Belyi and Shokalsky islands, Arctic Ocean, where the populations are mainly concentrated in summer, especially in order to compare them with greater white-fronted (Anser albifrons) and brent (Branta bernicla) geese that use the same food resources. The herbivores are shown to feed on more than 40 plant species on those islands. The more mobile species using more habitat types show more diverse diets, but both food diversity and food selectivity depend on their morphological and physiological features. Both white fronted goose populations are more abundant than both brent goose ones and continue growing, while the brent goose populations have a stable population trend. This agrees with a broader and less selective diet in the white-fronted goose compared to the brent goose. However, both reindeer populations on the islands, although showing the widest and least selective diet, undergo a sharp decline which is therefore not influenced by food competition. This allows us to suggest just the maintenance of the usual reservation rules on the islands that can provide at least equal initial conditions for all herbivore species for using the limited resources.

Over the past 15 years there has been a 39.2% decrease in Bewick swan numbers in the northern European wintering sites. At the same time, there has been a rapid numbers increase observed on the nesting grounds since the mid-1980's. We examine how the opposite trends in the numbers of the Bewick swan in the Russian tundra and in the northern European wintering sites are related. In 2014-2017 we conducted aerial surveys and estimated the numbers of Bewick swans and cygnets in the broods across the entire breeding range of the northern European population and also in Yamal, Baidaratskaya Bay, Dvuobye and Gydan Peninsula. The growing numbers in the nesting areas are hypothesized to be associated with the penetration of birds of Asian populations further west. Our counts data confirm that swans from the eastern part of the Nenetsky Autonomous Okrug (NAO) can form congestions in the Baydaratskaya Bay, from where they can migrate through the Dvuobye to other wintering areas. Telemetry data show that birds fly from the Baidaratskaya Bay in a very wide front, but do not fly to northern Europe. We assume that some of the birds passing the summer in the NAO are the swans of Asian origin which expand their range to the west and have reached the breeding range of the Northern European population.

The migration corridors of Bewick’s swan, which inhabits the Yamalo-Nenets Autonomous District, were identified in 2015–2017 using GPS-GMS transmitters. It was shown that even the individuals that inhabit the same region widely used different wintering sites. The birds that nest and molt in southern Yamal (Baydaratskaya Bay) were found to migrate through two corridors: the eastern corridor that leads to southeastern China and the western one that leads to the Caspian Sea, the Evros River delta, countries of Central and Middle Asia, and northwestern China. Fourteen key stopover sites were revealed. We explain the appearance of new Asian and European wintering sites by the general increase in the species’ numbers and believe that the decrease in the size of the Northern European population that has been observed since the mid-1990s is due to a loss of natural habitats. We have shown for the first time that the wintering range of Bewick’s swan with the revealed Asian wintering sites being taken into account is quite large. As the climate changes, some stopover sites can be used as wintering sites, which may lead to an even greater expansion of the wintering range of the species in the future.

This work studies the effect of the reduction of steppe and tundra landscapes in Northern Asia during the Late Pleistocene and Holocene climatic changes on the ranges of large herbivorous mammals. The relationship between a complex of characteristics of herbivore species and their landscape was evaluated. It is found that not only the Mongolian gazelle, saiga, and musk ox, but also the snow sheep, the ancestors of domestic sheep and goats, and probably the Amur goral may reduced their ranges during the late Quaternary landscape changes. The widening of the range of the sika deer, as well as the range of the Siberian musk deer associated exclusively with forest landscapes, can be explained by a reduction of open landscapes. Any significant changes in the ranges of roe deer, red deer, reindeer, elk, wild boar, steppe bison, mammoth, woolly rhinoceros, and ancestral and probably related forms of domestic horse and cattle could not be directly caused by landscape changes 17 000–7000 years ago, even if they coincide chronologically.

The Lesser Snow Goose (Anser caerulescens caerulescens) is one of the most abundant geese globally. Its nesting distribution area which mostly lies in North America is presently expanding, with the numbers over the last 50 years grown from 1 to 15 million. Yet this goose species which has been exterminated in Eurasia fails to recover its historical range. The only large breeding colony in Eurasia has persisted on Wrangel Island, where the birds share food resources with ruminants. To find out what prevents the geese from dispersal and the establishment of new colonies on the island, we estimated the trophic niche overlap and competitive advantages in habitat choice. We show that ruminants are stronger trophic competitors to geese, while in most of the habitat types associated with the goose colony the level of trophic competition and/or resource shortage is higher than in post-colonial ones, where the resources are more diverse and abundant. We conclude that, in the present conditions of goose numbers growth on Wrangel Island, neither the restoration of extinct nor the initiation of new colonies is hampered by resource shortage and/or the stronger competitors (ruminants). The factors related to the distribution of food resources and to competition fail to determine the choice of a nesting site. This probably concerns arctic Eurasia in general.

The lesser snow goose (Anser caerulescens caerulescens) has been exterminated across a vast area of Eurasia. At present, it is unable to regenerate there, though its population in North America has reached fifteen million. In Eurasia, the only major nesting colony still persists on Wrangel Island, where the geese use the trophic resources together with ruminants. An assessment of the competitive networks and the trophic interactions between the geese and the ruminants was performed. The analysis of the significance of the trophic niche overlap and the competitive advantages of geese in the habitat preferences has proved that the ruminants are stronger competitors for trophic resources than the geese. It has been ascertained that the levels of competition for trophic resources and/or resource shortages are higher across the habitats of most types associated with the goose colony. The level of the competition for trophic resources is lower, and the feed resources are more diverse and abundant in the habitats that are used by the geese after leaving the colony. It can be concluded that the shortage of resources and/or the stronger competitors for trophic resources (the ruminants) cannot prevent restoration of extinct colonies or the formation of new colonies with a recent increase in the size of the goose population on Wrangel Island. The distribution, abundance, and quality of trophic resources and the competition for them with ruminants do not determine the goose choice of a habitat for a nesting colony. The choice depends on the microclimate and, probably, on a range of other factors.

This paper deals with food selectivity in large herbivores of Eastern Mongolia, its factors, and their impact on the herbivore community structure. It is shown that, due to the degradation of vegetation, all studied herbivores display a significant selectivity level conditioned by their morpho–physiological features and spatial distribution. The selectivity seems to provide competitive advantages but no food niche differentiation. We suppose that herbivore communities in Eastern Mongolia, both human-controlled and wild, bear an increase of the small browser portion under pasture degradation. This, in turn, increases the degradation rate. This cyclic interaction shows a possible mechanism for the formation of endogenous crises in herbivore communities and can explain features of extinction events of large herbivores of the “Mammoth fauna.”

In Russia, the conservation of anseriformes is possible through the creation of temporary huntingfree zones during hunting season, especially in spring. A justification for creating such zones and outlining their boundaries (by analogy with the experience derived from the countries on North America) each season must be based on data on annual waterfowl monitoring. The present paper describes census experience drawn from the use of ultralight aviation for further delineating the key staging sites of waterfowl in western Siberia. To refine the duration of monitoring, observation data were combined with those derived from geese equipped with GSM-GPS transmitters. In the spring and autumn of 2012–2014, we covered over 50000 km of aerial surveys of 25 waterfowl species. A new method is advanced for assessing their numbers based on visual observations, flock photography, and modern statistics. We estimated the species densities in 16 habitat types delineated on the basis of Landsat imagery. In terms of this, a system is proposed for extrapolating the survey data on 25 waterfowl species onto model sites in western Siberia. Drops in the numbers of several mass game species were noted. Based on an evaluation of the habitat quality, ten waterfowl hunting-free zones were suggested and delineated. A GIS project was launched that incorporated the main migration routes, boundaries of the key sites, places of mass bird aggregations, and sites for the observation of rare, Red Data Book. A program of long-term monitoring and sustainable use of waterfowl in the study region is offered. Such an approach must also be applied to other regions of Russia.

Trends in the dynamics of herbivore community related to trophic competition in summer have been analyzed on Wrangel Island. The results show that the trophic spectra overlap considerably, resources are partitioned on the principle “weak competitors after strong competitors,” and community dynamics in the absence of extermination depend on specific competitive advantages related to the width of food spectrum. We conclude that the dynamics of this insular community prior to the establishment of nature reserve on the island have been determined by human activities, as well as the structure of arctic herbivore communities in general.