Large branchiopod Crustacea (Anostraca,Notostraca, Spinicaudata) of the Barents Region of Russia

The Russian Territory known as the Barents Region includes the large islands of Vaigatch and Kolguev, the archipelagos of Franz Joseph Land and Novaya Zemlya, and many small near shore islands in the Barents Sea subregion of the Arctic Ocean. With the exception of Franz Joseph Land, these islands and the Novaya Zemlya Archipelago are inhabited by seven species of large branchiopods: four species of Anostraca, Polyartemia forcipata S. Fischer, 1851, Artemiopsis bungei plovmornini Jaschnov, 1925, Branchinecta paludosaMüller, 1851 and Branchinectella media (Schmankewitsch, 1873); one Notostraca, Lepidurusarcticus (Kroyer, 1847); and two species of Spinicaudata, Caenestheria propinqua Sars, 1901and C. sahlbergi (Simon, 1886). This is a richer large branchiopod fauna than occurs in other comparable land areas of the Arctic Ocean. The northern most known occurrence of Branchinecta paludosa is at Ivanov Bay on the Novaya Zemlya Archipelago. This report includes some life history observations. This revised version was published online in August 2006 with corrections to the Cover Date.     

Demersal fish assemblages and spatial diversity patterns in the Arctic-Atlantic transition zone in the Barents Sea

Direct and indirect effects of global warming are expected to be pronounced and fast in the Arctic, impacting terrestrial, freshwater and marine ecosystems. The Barents Sea is a high latitude shelf Sea and a boundary area between arctic and boreal faunas. These faunas are likely to respond differently to changes in climate. In addition, the Barents Sea is highly impacted by fisheries and other human activities. This strong human presence places great demands on scientific investigation and advisory capacity. In order to identify basic community structures against which future climate related or other human induced changes could be evaluated, we analyzed species composition and diversity of demersal fish in the Barents Sea. We found six main assemblages that were separated along depth and temperature gradients. There are indications that climate driven changes have already taken place, since boreal species were found in large parts of the Barents Sea shelf, including also the northern Arctic area. When modelling diversity as a function of depth and temperature, we found that two of the assemblages in the eastern Barents Sea showed lower diversity than expected from their depth and temperature. This is probably caused by low habitat complexity and the distance to the pool of boreal species in the western Barents Sea. In contrast coastal assemblages in south western Barents Sea and along Novaya Zemlya archipelago in the Eastern Barents Sea can be described as diversity "hotspots"; the South-western area had high density of species, abundance and biomass, and here some species have their northern distribution limit, whereas the Novaya Zemlya area has unique fauna of Arctic, coastal demersal fish. (see Information S1 for abstract in Russian).     

A comparative analysis of the helminth fauna of kittiwake Rissa tridactyla (Linnaeus, 1758) and glaucous gull Larus hyperboreus Gunnerus, 1767 from different parts of the Barents Sea

The article is based on the results of helminthological observations made on kittiwake Rissa tridactyla and glaucous gull Larus hyperboreus in 1991-2001 in different areas of the Barents Sea (Eastern Murman coast, Franz Josef Land, Novaya Zemlya, Spitzbergen). 18 helminth species (2 trematodes, 11 cestodes, 4 nematodes, and 2 acanthocephalans) were recorded in the kittiwakes and 19 (3 trematodes, 9 cestodes, 5 nematodes and 2 acanthocephalans) species were recorded in the glaucous gulls. Trematodes were absent in the birds collected at the Franz Josef Land and the northern island of Novaya Zemlya. 3 trematode species, namely Gymnophallus sp. (somateria?), Microphallus sp. 1 (M. pseudopygmaeus), and Cryptocotyle lingua were found in the glaucous gulls of western Spitzbergen. It was supposed that the life cycles of these parasites can be completed there. On the other hand, coastal ecosystems of Arctic archipelagoes turn out to be favourable for the transmission of some cestodes. This is closely connected with the regional traits in the marine bird diet, namely the increase of the amphipod (intermediate hosts of hymenolepidids and some dilepidids) and polar cod (supposed second intermediate host for some tetrabothriids) portion in Arctic. As a result, cestodes are the base of the helminth fauna of kittiwakes and glaucous gulls of the Barents Sea, by their species richness, prevalence and abundance. Nematodes and acanthocephalans were represented by a few species with low infection intensity. The main ecological factors affected the regional difference in the species richness and abundance of the helminths parasitising kittiwakes and glaucous gulls in the Barents Sea are proposed. Those are regional climatic features and regional traits in the behaviour and food priorities of birds, and also the distribution of the helminths intermediate hosts, invertebrates and fishes. The phenomenon of host specificity lowering with respect to the definitive host was recorded in some cestode species (Microsomacanthus diorchis, M. microsoma, and Arctotaenia tetrabothrioides) on the border of their distribution ranges, the coastal ecosystems of Arctic.     

Breeding and moulting locations and migration patterns of the Atlantic population of Steller's eiders Polysticta stelleri as determined from satellite telemetry

This study was designed to determine the spring, summer, autumn, and early winter distribution, migration routes, and timing of migration of the Atlantic population of Steller's eiders Polysticta stelleri. Satellite transmitters were implanted in 20 eiders captured in April 2001 at Vadsø, Norway, and their locations were determined from 5 May 2001 to 6 February 2002. Regions where birds concentrated from spring until returning to wintering areas included coastal waters from western Finnmark, Norway, to the eastern Taymyr Peninsula, Russia. Novaya Zemlya, Russia, particularly the Mollera Bay region, was used extensively during spring staging, moult, and autumn staging; regions of the Kola, Kanin, and Gydanskiy peninsulas, Russia, were used extensively during spring and moult migrations. Steller's eiders migrated across the Barents and Kara seas and along the Kara Sea and Kola Peninsula coastal waters to nesting, moulting, and wintering areas. The majority of marked eiders (9 of 15) were flightless in near‐shore waters along the west side of Novaya Zemlya. Eiders were also flightless in northern Norway and along the Kanin and at Kola Peninsula coasts. We compare and contrast natural history characteristics of the Atlantic and Pacific populations and discuss evolutionary and ecological factors influencing their distribution.     

Breeding and moulting locations and migration patterns of the Atlantic population of Steller's eiders Polysticta stelleri as determined from satellite telemetry

This study was designed to determine the spring, summer, autumn, and early winter distribution, migration routes, and timing of migration of the Atlantic population of Steller's eiders Polysticta stelleri . Satellite transmitters were implanted in 20 eiders captured in April 2001 at Vadsø, Norway, and their locations were determined from 5 May 2001 to 6 February 2002. Regions where birds concentrated from spring until returning to wintering areas included coastal waters from western Finnmark, Norway, to the eastern Taymyr Peninsula, Russia. Novaya Zemlya, Russia, particularly the Mollera Bay region, was used extensively during spring staging, moult, and autumn staging; regions of the Kola, Kanin, and Gydanskiy peninsulas, Russia, were used extensively during spring and moult migrations. Steller's eiders migrated across the Barents and Kara seas and along the Kara Sea and Kola Peninsula coastal waters to nesting, moulting, and wintering areas. The majority of marked eiders (9 of 15) were flightless in near-shore waters along the west side of Novaya Zemlya. Eiders were also flightless in northern Norway and along the Kanin and at Kola Peninsula coasts. We compare and contrast natural history characteristics of the Atlantic and Pacific populations and discuss evolutionary and ecological factors influencing their distribution.     

Distribution of beluga whales (Delphinapterus leucas) in the Russian Arctic seas according to the results of expedition aboard RV Mikhail Somov, September–November 2010

Data on the distribution of marine mammals, including beluga whales (Delphinapterus leucas Pallas, 1766), in the Arctic are scarce because of various causes and conditions, including the vast expanses of the region, its poor accessibility, severe climate, long polar night, and high cost of research. Nevertheless, the results of aerial observations during ice reconnaissance and onboard observations during sea voyages (Kleinenberg et al., 1964; Geptner et al., 1976; Belikov, Boltunov, and Gorbunov, 2002; Belikov and Boltunov, 2002; Ezhov, 2005; Matishov and Ognetov, 2006; Biologiya i okeanografiya??, 2007; Lukin and Ognetov, 2009) have provided a general idea of the distribution pattern of beluga whales in the Russian Arctic seas. More detailed data concern the distribution of these whales in the White Sea, where aerial surveys of the water area were performed previously and have been resumed in recent years (Nazarenko et al., 2008; Glazov et al., 2010, 2011). The relevant data on the Barents, Kara, Laptev, and East Siberian seas are much poorer. In the summer (ice-free) period, beluga whales concentrate in coastal waters. They have been recorded most frequently off Franz Josef Land, Novaya Zemlya, Vaygach Island, and in Czech Bay in the Barents Sea; in Baydaratskaya Bay, Gulf of Ob, and Yenisei Gulf in the Kara Sea; off the northeastern coast of Taimyr and in estuaries of the Anabar, Olenyok, and Lena rivers in the Laptev Sea; and in the estuaries of the Indigirka (where the whales come from the west) and the Kolyma and Ked??ma rivers (where they come from the east) in the East Siberian Sea. The amount of information obtained in other seasons is very limited. In autumn, mass migration of beluga whales from the Kara Sea to the Barents Sea have been recorded in the Karskie Vorota Strait and off Cape Zhelaniya in the north of Novaya Zemlya. In winter, almost no records of these whales have been made in the Kara, Laptev, and East Siberian seas. These data are based on previous observations and have practically not been complemented in recent years.     

Specific features of the spatial and temporal distribution of the White Sea population of harp seal

Analysis of the data obtained during aerial survey of sea mammals in the 1980s–1990s (White and Barents seas) has revealed that, during all the seasons of the year, harp seals of the White Sea population form two types of aggregations which differ in size and some ecological features. Large herds of seals (tens of thousands of individuals) are able to occupy areas extending tens and even hundreds of kilometers. Harp seals prefer to inhabit the northern part of the population range (Barents Sea), whereas the southern part (White Sea) is mainly used for reproduction and molting. Small herds (several hundred animals) can be scattered over vast territories, but they tend to dwell in the southern part of the area including the White Sea and southern areas of the Barents Sea. The opportunity to distinguish between these two types of aggregations makes it possible to study the biological features of each of them and to specify characteristics of the species biology.     

Inter-breeding movements of common guillemots (Uria aalge) suggest the Barents Sea is an important autumn staging and wintering area

Seabird movements outside the breeding season are generally poorly known, but can cover thousands of square km and a multitude of habitats, feeding conditions and potential threats. During the last decades, many seabird species in the North Atlantic have experienced large reductions in population size and breeding success, probably caused by reduced prey abundance caused by climate alterations and overfishing. One of these seabird species is the common guillemot. We used global location sensors (geolocators) to identify inter-breeding movements of 10 individuals breeding at Sklinna, a colony off the coast of Central Norway during July 2009–July 2010. All individuals moved northwards after breeding, and eight of them (80?%) entered the Barents Sea where they probably completed their moult. Three individuals moved southwards before the winter, but in total, half of the individuals stayed in the Barents Sea during winter. The other half wintered off the coast of Central Norway–Lofoten. The fact that all individuals moved northwards to winter was surprising as ringing recoveries suggest they also moves southwards (to the Skagerrak area) to winter. This suggests variation (individual or annual) in wintering movements and calls for a multi-year geolocator study at a number of colonies. Much of the area in the Barents Sea–Lofoten area is classified as vulnerable with respect to specific environmental pressures such as oil pollution and other anthropogenic factors, and the importance of the Barents Sea as a major wintering area for common guillemots from central Norway certainly has implications for the management authorities.     

Meiobenthos of the Former Nuclear Test Area and Nuclear Waste Disposal Grounds around the Novaya Zemlya Archipelago (Barents and Kara Seas)

The taxonomic composition and quantitative distribution of the meiobenthos were studied in materials collected from one of the former nuclear test sites by the Novaya Zemlya Archipelago in Chernaya Guba (Barents Sea) and from the grounds of nuclear waste disposal along the east coast of the Archipelago from Abrosimov Bay to Stepovoi Bay and the region of Novozemel'skaya Hollow (Kara Sea). Foraminifera and free living nematodes were the most numerous groups, and foraminifera prevailed in terms of biomass in the entire area studied. No correlation of the parameters of the meiobenthic communities with varying depth and type of ground was revealed. It was established that the taxonomic diversity increased and population density decreased with an increase in the concentration of ¹³⁷Cs. It was suggested that meiobenthic communities are able to respond quickly to the deterioration of environmental radioactivity, varying their taxonomic composition and parametrical indexes.     

The mortality of the planktonic copepod <Emphasis Type="Italic">Oithona similis</Emphasis> Claus, 1866 (Copepoda: Cyclopoida) in the Barents and White Seas

The mortality rates of the copepodite IV-copepodite V and copepodite V-adult individuals pairs in the populations of one of the most common species of planktonic copepod, Oithona similis, were estimated for the first time in the Barents and White seas. The average parameters were 0.060 and 0.082/day, respectively, in the Barents Sea and 0.166 and 0.120/day in the White Sea. In the Barents Sea, the mortality rates of O. similis significantly increased with an increase in water temperature and in the White Sea a significant decrease occurred with an increase in salinity. It was concluded that the mortality rate of this species is determined first by abiotic factors and that biotic factors are of secondary significance.     

Completeness of seasonal molting in passerine birds (Aves,Passeriformes) in Northwestern Siberia

This paper considers the variability of the completeness of seasonal molting in passerine birds of the forest tundra and tundra areas of Western Siberia. All variants of passerine birds of North Eurasia known for molting—from complete postjuvenile molting at hatching places to its absence and complete postjuvenile molting at wintering places or at migratory routes, from complete prebreeding molting at wintering places to its absence, and from complete postbreeding molting at nesting places to complete molting at wintering places or at migratory routes—are shown. The factors affecting the completeness of molting are discussed—the properties of adaptation to the subarctic region, length of the migratory route, and photoperiodic conditions during molting. The completeness of molting is most significantly affected by the duration of daylight.     

The distribution and biology of the cestode Eubothrium parvum in capelin, Mallotus villosus, (Pallas) in the Barents Sea, and its use as a biological tag

Samples of Eubothrium parvum were obtained from capelin Mallotus villosus at 55 stations throughout the Barents Sea and from Balsfjord, North Norway. The parasite is distributed widely throughout the Barents Sea, but both incidence and intensity of infection are higher in the regions off Murmansk and the Kola peninsula, and Spitsbergen. E. parvum exhibits a seasonal peak in maturation and probably also in acquisition of new infections. The incidence of infection is greatest in 1 + fish, whereas the intensity is more independent of host age. It is suggested that the parasite requires only a single intermediate host, a plank-tonic copepod, and its distribution in relation to age of host is a reflection of the dietary preference shown by young capelin for copepods. The frequency distribution of E. parvum in capelin was over-dispersed in Balsfjord, where infection levels of between 1 and 28 parasites per fish were encountered in all samples, but under-dispersed in the Barents Sea, where infections of more than four parasites per fish were never found and even infections with three and four parasites were very local. It is suggested that the underdispersion is due to a very low probability of infection in the open waters of the sea. Although the presence of E. parvum cannot be used as a biological tag for capelin, its abundance and frequency distribution can. The difference in frequency distribution and the failure to find any heavily infected fish in the Barents Sea confirm the suggestion that the capelin of Balsfjord form a local isolated population, which does not migrate into the Barents Sea. The differences in infection levels within the Barents Sea suggest the further possibility that there are at least two stocks of capelin there, but this requires further investigation and confirmation.     

On the issue of influence of coastal seabird colonies on adjacent pelagic communities of the Kola Peninsula

According to previously obtained data, seabird colonies, as a biotic factor, exert a substantial influence on communities of some coastal waters around the Novaya Zemlya archipelago. In the current study, an attempt has been made to assess the degree of the impact of seabird colonies on planktonic assemblages in the coastal waters of the Kola Peninsula. A study of phyto- and zooplankton near the colony on Cape Gorodetsky (Rybachy Peninsula) did not reveal any substantial differences in the qualitative and quantitative composition of this community in comparison with the other coastal waters of the Barents Sea. The lack of influence on the coastal biota can be explained by the low abundance of birds in the colonies, as well as by the effect of the Murman Coastal Current, which carries away and disperses the biogenic matter that enters the aquatic environment with guano.     

Phylogenetic diversity in sulphate-reducing bacterial communities from oxidised and reduced bottom sediments of the Barents Sea

In the bottom sediments from a number of the Barents Sea sites, including coastal areas of the Novaya Zemlya, Franz Josef Land, and Svalbard archipelagos, sulphate reduction rates were measured and the phylogenetic composition of sulphate-reducing bacterial (SRB) communities was analysed for the first time. Molecular genetic analysis of the sequences of the 16S rRNA and dsrB genes (the latter encodes the β-subunit of dissimilatory (bi)sulphite reductase) revealed significant differences in the composition of bacterial communities in different sampling stations and sediment horizons of the Barents Sea depending on the physicochemical conditions. The major bacteria involved in reduction of sulphur compounds in Arctic marine bottom sediments belonged to Desulfobulbaceae, Desulfobacteraceae, Desulfovibrionaceae, Desulfuromonadaceae, and Desulfarculaceae families, as well as to uncultured clades SAR324 and Sva0485. Desulfobulbaceae and Desulfuromonadaceae predominated in the oxidised (E_h = 154–226 mV) upper layers of the sediments (up to 9% and 5.9% from all reads of the 16S rRNA gene sequences in the sample, correspondingly), while in deeper, more reduced layers (E_h = ?210 to ?105 mV) the share of Desulfobacteraceae in the SRB community was also significant (up to 5%). The highest relative abundance of members of Desulfarculaceae family (3.1%) was revealed in reduced layers of sandy-clayey sediments from the Barents Sea area affected by currents of transformed (mixed, with changed physicochemical characteristics) Atlantic waters.

     

Complex postbreeding molt strategies in a songbird migrating along the East Asian Flyway,the Pallas’s Grasshopper Warbler Locustella certhiola

Molt strategies have received relatively little attention in current ornithology, and knowledge concerning the evolution, variability and extent of molt is sparse in many bird species. This is especially true for East Asian Locustella species where assumptions on molt patterns are based on incomplete information. We provide evidence indicating a complex postbreeding molt strategy and variable molt extent among the Pallas's Grasshopper Warbler Locustella certhiola, based on data from six ringing sites situated along its flyway from the breeding grounds to the wintering areas. Detailed study revealed for the first time that in most individuals wing feather molt proceeds from the center both toward the body and the wing‐tip, a molt pattern known as divergent molt (which is rare among Palearctic passerines). In the Russian Far East, where both breeding birds and passage migrants occur, a third of the adult birds were molting in late summer. In Central Siberia, at the northwestern limit of its distribution, adult individuals commenced their primary molt partly divergently and partly with unknown sequence. During migration in Mongolia, only descendantly (i.e., from the body toward the wing‐tip) molting birds were observed, while further south in Korea, Hong Kong, and Thailand the proportion of potential eccentric and divergent feather renewal was not identifiable since the renewed feathers were already fully grown as expected. We found an increase in the mean number of molted primaries during the progress of the autumn migration. Moderate body mass levels and low‐fat and muscle scores were observed in molting adult birds, without any remarkable increase in the later season. According to optimality models, we suggest that an extremely short season of high food abundance in tall grass habitats and a largely overland route allow autumn migration with low fuel loads combined with molt migration in at least a part of the population. This study highlights the importance of further studying molt strategy as well as stopover behavior decisions and the trade‐offs among migratory birds that are now facing a panoply of anthropogenic threats along their flyways.     

Redescription and new data on <Emphasis Type="Italic">Microsomacanthus diorchis</Emphasis> (Fuhrmann, 1913) (Cestoda: Hymenolepididae)

Microsomacanthus diorchis (Fuhrmann, 1913) is redescribed and illustrated on the basis of the type-material and new findings from common eider Somateria mollissima captured in Iceland and specimens from the same host species from the Barents, White and Bering Seas. A lectotype is designated and an amended diagnosis is provided. The main differentiating features of M. diorchis are the size and shape of rostellar hooks and the cirrus, the well-marked delay in the antiporal testis development and the bow-shaped uterus. This parasite is shown to be specific to S. mollissima for both Atlantic and Pacific populations of the host. Hymenolepis (Microsomacanthus) somateriae of Bishop & Threlfall (1974) [nec M. somateriae Ryzhikov, 1965] is recognised as a synonym of M. diorchis (Fuhrmann, 1913). The taxonomic position of the species described as Aploparaksis murmanica Baylis, 1919 from common eider is discussed.     

The biodiversity of zooplankton communities of the west arctic seas

Based on the data from ten cruises that were carried out in 2001–2009, the structure of zooplankton communities was assessed in the Western Arctic seas using the estimated biodiversity indices. The greatest number of taxa was revealed in the south, southeast, and north of the Barents Sea. The average number of taxa in the sample was at a maximum off the coast of the Svalbard Archipelago. The greatest value of the Shannon index was registered within the Murmansk coastal water mass (Barents Sea) and Svalbard Archipelago. The median values of the evenness of the abundance of fauna were 0.5–0.6. A trend to a reduction of the biodiversity parameters of zooplankton communities with increasing square of water area water area was found. An inverse correlation between the Shannon and evenness indices for the total zooplankton abundance was revealed.     

Climate and cyclic hydrobiological changes of the Barents Sea from the twentieth to twenty-first centuries

The Barents Sea is a transition zone between North Atlantic and Arctic waters, so its marine ecosystem is highly sensitive to climate dynamics. Understanding of marine biota response to climate changes is necessary to assess the environmental stability and the state of marketable biological resources. These processes are analyzed using a database from the Murmansk Marine Biological Institute which holds oceanographic and hydrobiological data sets collected for more than 100?years along the meridional Kola Transect in the Barents Sea. The data demonstrate high variability in thermal state of the upper layer of the Barents Sea, which is regulated by varying the inflow of Atlantic water and by regional climate. At irregular intervals, cold periods with extended seasonal ice cover are followed by warm periods. The most recent warm period started in the late 1980s and reached its maximum from 2001 to 2006. These cyclic changes in hydrologic regime across the twentieth century and first decade of the twenty-first century are reflected (with a specific lag of 1–5?years) by changes in species composition, as well as abundance and distribution of boreal and arctic groups of macrozoobenthos and fish fauna. For instance, cod and cod fisheries in the Barents Sea are closely linked to the marine climate. Furthermore, Kamchatka crab stock recruitment benefited from the warm climate of 1989 and 1990. In general, studies in this region have shown that climatic dynamics may be assessed using biological indices of abundance, biomass, and migration of marine organisms, including commercial species.     

New Data on the Distribution of Lamprey <Emphasis Type="Italic">Petromyzon marinus</Emphasis> and <Emphasis Type="Italic">Lethenteron camtschaticum</Emphasis> (Petromyzontidae) in Barents and White Seas

Information about the sites of catches of the sea lamprey Petromyzon marinus in the western Barents Sea and Arctic lamprey Lethenteron camtschaticum in the Barents and White seas is presented based on the data of trawl surveys performed in 2004?2016. It is demonstrated that sea lamprey is occasionally encountered in the western Barents Sea; nine specimens have been recorded during the entire period of surveys. The northernmost point of a capture of sea lamprey is located near 76° N and the easternmost point is at 31°15′ E. Arctic lamprey is not numerous in the Barents and White seas; a total of 66 and 17 specimens have been caught, respectively. Its local aggregations are found in the southeastern part of the Barents Sea and in Dvina Bay in the White Sea. Arctic lamprey penetrates to the north to 76° N and into the central part of the Barents Sea.