High Arctic Archipelago Of Svalbard Research Articles

Disease transmission in an extreme environment: Nematode parasites infect reindeer during the Arctic winter

Parasitic nematodes are found in almost all wild vertebrate populations but few studies have investigated these host–parasite relationships in the wild. For parasites with free-living stages, the external environment has a major influence on life-history traits, and development and survival is generally low at sub-zero temperatures. For reindeer that inhabit the high Arctic archipelago of Svalbard, parasite transmission is expected to occur in the summer, due to the extreme environmental conditions and the reduced food intake by the host in winter. Here we show experimentally that, contrary to most parasitic nematodes, Marshallagia marshalli of Svalbard reindeer is transmitted during the Arctic winter. Winter transmission was demonstrated by removing parasites in the autumn, using a novel delayed-release anthelmintic bolus, and estimating re-infection rates in reindeer sampled in October, February and April. Larval stages of nematodes were identified using molecular tools, whereas adult stages were identified using microscopy. The abundance of M. marshalli adult worms and L4s increased significantly from October to April, indicating that reindeer were being infected with L3s from the pasture throughout the winter. To our knowledge, this study is the first to experimentally demonstrate over-winter transmission of a gastro-intestinal nematode parasite in a wild animal. Potential mechanisms associated with this unusual transmission strategy are discussed in light of our knowledge of the life-history traits of this parasite.

Two new species of aphid parasitoids (Hymenoptera, Braconidae, Aphidiinae) from the high arctic (Spitsbergen, Svalbard)

The high arctic Svalbard archipelago is characterized by a low insect species richness explained by both extreme living conditions and insularity. Here, we described two new species of Hymenopteran parasitoids found in Spitsbergen, the main island of Svalbard, using aphids as hosts. We named the first one Diaeretellus svalbardicum (Hymenoptera: Braconidae) because of morphological similarities with other European members of the Diaeretellus genus. D. svalbardicum parasitizes exclusively the aphid Acyrthosiphon svalbardicum, a species endemic to Svalbard. We also reported in D. svalbardicum a unique case of wing polymorphism with macropterous and micropterous forms in both genders. We named the second newly described parasitoid species Aphidius leclanti because of morphological similarities with other members of the Aphidius genus. Contrarily to D. svalbardicum, A. leclanti exploits the only two aphid species regularly found in Spitsbergen, A. svalbardicum and Sitobion calvulum.

Echinococcus multilocularis in Svalbard, Norway: Microsatellite genotyping to investigate the origin of a highly focal contamination

Echinococcus multilocularis is a threatening cestode involved in the human alveolar echinococcosis. The parasite, mainly described in temperate regions of the Northern hemisphere was described for the first time in 1999 in the High Arctic Svalbard archipelago, Norway. The origin of this contamination could be due to an anthropogenic introduction from mainland Europe by domestic dogs or with the introduction of the sibling vole, perhaps from mainland Russia (St. Petersburg area), or with roaming Arctic foxes, known as the main definitive host of the parasite in Arctic regions. The genetic diversity of E. multilocularis in Svalbard was investigated here for the first time by genotyping using EmsB microsatellite and compared to other genotyped populations in the main worldwide endemic areas. We found low polymorphism amongst the 27 metacestode isolates from sibling voles trapped in the core of the distribution area of the vole on Svalbard. E. mutilocularis Arctic populations, using the Arctic fox as the definitive host, were genetically separated from European temperate populations that use the red fox, but closely related to St. Lawrence Island samples from Alaska. The result is inconsistent with the hypothesis of an anthropogenic introduction from mainland Europe, but can be seen as consistent with the hypothesis that Arctic foxes introduced E. multilocularis to Svalbard.

The mesostigmatid mite (Acari: Parasitiformes) fauna of Svalbard: a revised inventory of a high Arctic archipelago

The need for comprehensive studies of the invertebrate fauna in the high Arctic is increasingly acknowledged in order to more fully understand ecosystem functioning, resilience and to project future changes in the biodiversity and species ranges. Information on the mesostigmatid fauna in the high Arctic is scarce and scattered. Large regions of the high Arctic archipelago of Svalbard, including most of the areas in the east of the island group, have never been surveyed for the mesostigmatid fauna. Furthermore, most of the current knowledge on the mesostigmatid fauna of this important region in the European high Arctic originates from studies in the early 20 th century. Much of the associated slide material no longer exists, either being mislaid or deliberately destroyed, resulting in an ambiguous and potentially misleading mesostigmatid fauna checklist in which identifications and potential synonyms cannot be reliably assessed. Determination of fresh material sampled between 2007–2010 may be an ideal procedure to resolve the great number of uncertainties about the mesostigmatid fauna of the Svalbard archipelago. Twelve out of the 27 species recorded from the Svalbard archipelago were found in the new samples collected from a large number of localities and microhabitats. No new species were identified in the current campaign, and most of the non-observed species are considered to be past missidentifications or potential synonyms. Combining this study with recent publications provides a total mesostigmatid mite diversity for Svalbard of 22 species. This represents the most accurate checklist of the mesostigmatid mite fauna of the archipelago to date.

Extrapolating herbivore-induced carbon loss across an arctic landscape

A high proportion of the global soil carbon stock is stored in tundra soils. However, populations of arctic-breeding migratory geese including pink-footed geese, Anser brachyrhynchus, are increasing due to agricultural changes and conservation measures in their wintering grounds. Foraging by these geese, which is widespread in extent, reduces the quantity of carbon stored in arctic tundra ecosystems. Here, the potential carbon loss caused by foraging pink-footed geese is modelled across the high-arctic archipelago of Svalbard, combining field experiments, habitat maps and published spatial models of foraging. The carbon loss caused by foraging geese was estimated three growing seasons following perturbation allowing for some recovery to take place. The carbon loss caused by 1-year worth of grubbing was estimated to be 1,700 tonnes, or 37 kg per goose. A total of over 340,000 tonnes of carbon could be affected given an unlimited increase in goose population. Estimated losses were mostly from wetter habitats, which are both carbon rich and highly selected for by foraging geese. The across-landscape carbon loss caused by geese is not great in magnitude in comparison to expected climate-driven carbon losses; however, it is locally severe, and demonstrates how migratory connectivity links processes, such as agricultural change and conservation measures in temperate Europe with carbon dynamics in the high arctic.

Predicting habitat use by ringed seals ( Phoca hispida) in a warming Arctic

Models predicting the spatial distribution of wild animals are essential for conservation purposes (e.g. conservation plan formulation and reserve selection) and for assessment of ecological impacts of factors such as pollution and climate change. When a species’ habitat use depends on highly dynamic environmental conditions, predictive models should be constructed for specific time periods, taking into account the existing spatial distribution of the relevant habitat conditions. In the case of ringed seals ( Phoca hispida), habitat use is intimately connected with sea ice. In the High Arctic Archipelago of Svalbard, ringed seals have two different tactics for selection of large-scale summer habitat. Some individuals spend summer in coastal (inshore) areas, while others migrate offshore to the southern limits of the northern sea ice edge. The predicted decline of the sea ice extension in the Arctic is likely to critically affect the profitability of this latter foraging-migration tactic. Two modelling approaches were used in this study to explore when impacts are likely to occur. One approach explored small-scale habitat use within the two types of summer areas using habitat residency functions. These functions were empirically derived from statistical Cox proportional hazards (CPH) models fit to spatial data on seal residency times ( i.e., first-passage times) and local habitat features such as ice conditions. These functions predict the probability of using a given area longer than a given time. They were subsequently used to produce cartographic predictions of habitat use intensity for different times of the year, under various scenarios for sea ice conditions. Such dynamic predictions of animal space use (in space and time), can have wide applications for studies of other marine and terrestrial species that are based on data collected from telemetry. In the second approach, data from satellite telemetry and ringed seals energetics during summer were combined to construct a model for ringed seal blubber mass gain during summer. This model was then used to predict the profitability of offshore migrations as a function of the distance to the sea ice edge. This distance is expected to increase in a warmer climate. Migrations to offshore ice edges were predicted to become energetically unprofitable for ringed seals if the sea ice retreats further than 600–700 km from Svalbard.

Novel Rumen Bacterial Diversity in Two Geographically Separated Sub-Species of Reindeer

Svalbard reindeer (Rangifer tarandus platyrhynchus) live under austere nutritional conditions on the high-arctic archipelago of Svalbard, while semi-domesticated Norwegian reindeer (R. tarandus tarandus) migrate between lush coastal summer pastures and inland winter pastures with lichens on mainland Norway. Svalbard reindeer are known to have high rumen concentrations of cellulolytic bacteria, ranging from 15% of the viable population in summer to 35% in winter, compared to only 2.5% in Norwegian reindeer. Their rumen bacterial diversity was investigated through comparative analyses of 16S rRNA gene sequences ( approximately 1.5 kb in length) generated from clone libraries (n = 121) and bacterial isolates (n = 51). LIBSHUFF comparisons of the composition of the two 16S rRNA libraries from Norwegian reindeer showed a significant effect of artificial feeding compared to natural pasture, but failed to yield significant differences between libraries from Norwegian reindeer and Svalbard reindeer. The combined sequences from reindeer were not significantly different from those reported in wild Thompson's gazelle in Kenya but did differ from those reported in domestic cattle in Japan. A total of 90 distinct operational taxonomic units (OTUs) were identified by employing a criterion of 97% similarity, while the Chao1 index estimated the reindeer bacterial rumen population richness at 698 OTUs. The majority of the clone library sequences (92.5%) represented novel strains with <97% identity to any known sequence in the public database, most of them affiliated with the bacterial phylum Firmicutes (low G+C Gram-positives) related to the order Clostridiales (76.7%), while Gram-negative bacteria in the Bacteriodales (Prevotella-Bacteroides group) contributed to 22.5%. Also, six of the isolates were putatively novel strains, possibly representing new species in the Clostridium subphylum (cluster XIVa), Actinomyces and Butyrivibrio.

Terrestrial and Freshwater Invertebrate Fauna of the High Arctic Archipelago of Svalbard

An overview of the terrestrial and freshwater invertebrate fauna of the High Arctic archipelago of Svalbard is presented. Sixty seven additional species to the previous checklist are listed and the described terrestrial and freshwater invertebrate fauna of Svalbard now stands at 1,107 species. Species presented are cross referenced to the literature. A brief comparison with the invertebrate fauna of Greenland indicates that Svalbard may be under-represented in Hymenoptera, Hemiptera and Lepidoptera but over-represented in Collembola and Acari. However, since 82% of Svalbard primary source manuscripts originate from three locations along the west coast, there is a resulting likely bias in our knowledge of the invertebrate fauna. The west coast has a mild climate for the northerly latitude due to the influence of the West Spitsbergen Current, a northerly flowing branch of the North Atlantic Drift. The faunistically poorly known east coast is hypothesised to have a different invertebrate fauna due to the predominant winds and currents originating from the north east and hence this coast will have a different history of immigration and colonization from the west coast. The use of checklists is therefore cautioned due to possible sampling bias and omissions created by a concentration of work on popular groups and at a limited number of localities. However, this does not detract from their importance as baseline databases, especially during a period of rapid environmental change.

Ocean temperature oscillations enable reappearance of blue mussels Mytilus edulis in Svalbard after a 1000 year absence

We report the first observations of settled blue mussels Mytilus edulis L. in the high Arctic Archipelago of Svalbard for the first time since the Viking Age. A scattered population was discovered at a single site at the mouth of Isfjorden in August 2004. Our data indicate that most mus- sels settled there as spat in 2002, and that larvae were transported by the West Spitsbergen Current northwards from the Norwegian coast to Svalbard the same year. This extension of the blue mussels' distribution range was made possible by the unusually high northward mass transport of warm Atlantic water resulting in elevated sea-surface temperatures in the North Atlantic and along the west coast of Svalbard.

Assessment of Elevated Radionuclide Levels in Soils Associated with an Avian Colony in a High Arctic Environment

This article presents the results of an investigation into the occurrence of elevated levels of radionuclides in soils associated with a seabird colony in the Arctic. Soils and other materials were collected from a seabird colony (primarily composed of kittiwakes) in Kongsfjorden, located in the High Arctic archipelago of Svalbard. The samples were analyzed for a suite of gamma emitting natural and anthropogenic radionuclides, including 137Cs and nuclides of the 238U and 232Th series, to establish the level of enrichment and the behavior of the radionuclides in the immediate area. The results indicate that soils near the colony exhibit enrichment factors of 8 for 137Cs, 5 for 238U and 2 for 226Ra compared to the nuclide content of soils from the general area. The spatial patterns of the nuclides in the soil are consistent with enrichment of the soil via run-off draining from a large accumulation of fecal and nesting material that has developed at the base of the colony. 137Cs ingress to the soil appears to have peaked at some point in the past as patterns of enrichment at the colony are different to those exhibited by 238U, which must be assumed to be a steady state contribution. The means of introduction of radionuclides to the colony remains unclear but the transfer of 137Cs from the marine environment to the terrestrial environment via the food chain and deposition of feces is discussed.

Recent Environmental Change and Atmospheric Contamination on Svalbard as Recorded in Lake Sediments – an Introduction

This paper outlines an interdisciplinary project on recent environmental change and atmospheric contamination on the high Arctic archipelago of Svalbard (76°30′N–80°30′N). It describes the rationale and aims of the project and summarises the location, climate, geology, vegetation, and land-use of Svalbard.

Variation in extraction efficiency between juvenile and adult oribatid mites: Ameronothrus lineatus (Oribatida, Acari) in a Macfadyen high-gradient canister extractor

Summary A population of Ameronothrus lineatus (Acari, Oribatida) found living on homogeneous Cyanobacteria mats in Coles Bay on the high arctic archipelago of Svalbard, was used to study differential extraction efficiency between life cycle stages in a high-gradient dynamical extractor. The great advantage with this substrate was that the mites were easily seen on the Cyanobacteria surface and could be sampled by hand, and that juveniles in the pre-moult quiescent stage could be identified and sampled. Extracted specimens, as well as animals remaining on the surface of the samples after extraction, were counted, and accurate stage-specific extraction efficiencies were calculated. The experiment was carried out in June when no immatures had yet entered the pre-moult quiescent stage. Efficiencies of active mites varied from 29–36 % for juvenile instars to 75 % in adults. This demonstrated difference between adults and juveniles is reinforced by the fact that each juvenile instar includes a considerable period in the inactive pre-moult stage, remaining on the samples during a dynamic extraction. To investigate the occurrence of quiescence through the growth season, the Coles Bay population was regularly sampled during summer 1998. Quiescence, and hence moulting, was found to be highly synchronised. In population studies based on dynamical extraction, a synchronous quiescent stage will lead to time dependent biases in estimates of density and demography. These sources of sampling error, generally lower extraction efficiency of immatures as well as a pre-moult quiescent stage (possibly synchronised), have hardly been emphasised in population studies on oribatid mites. A field study of A. lineatus comparing proportions of adults in two populations – the one in Coles Bay where mites were hand sampled from the Cyanobacteria mats, and another one from Advent Valley where mites were dynamically extracted from soil – was used to illustrate the effect of these sources of sampling error. We suggest one means to address this problem.

The Brief Period of Spring Migration, Short Marine Residence, and High Return Rate of a Northern Svalbard Population of Arctic Char

Abstract Arctic char Salvelinus alpinus, in the high-Arctic archipelago of Svalbard, entered the Dieset River (79°10′N) immediately after ice breakup in late June (1991–1993), and within 48 h almost half the migrating population had left the lakes where they spent the winter. The majority of the anadromous char descended into the sea within 3 weeks of the melt. The temporal pattern of emigration was independent of body size. The average residence time at sea of the char was 33.6 d, and the maximum was 56 d. The duration of the seawater sojourn was independent of body size. However, the combined time of downstream migration and marine residence was inversely related to body length in early migrating char. Fish that migrated to the sea early tended to stay there longer. The overall return rate ranged from 33.3% for the smallest (15.1–20 cm) to 75.0% for the largest (45.1–50 cm) char, averaging 51.5%. The average return rate for fish shorter than 25.1 cm (first-time migrants) was 42.5%. The upstream run star...

Functional Anatomy of the Omasum in High Arctic Svalbard Reindeer (Rangifer tarandus platyrhynchus) and Norwegian Reindeer (Rangifer tarandus tarandus)

The structure and fill of the omasum was investigated in summer and in winter in adult female reindeer living on the polar desert and tundra of the high Arctic archipelago of Svalbard and in sub-Arctic mountain habitats in northern Norway. The mean total mass of the omasum in non-lactating adult female Svalbard reindeer was 467 g (0.65 g per 100 g live body mass (BM)) in September and 477 g (1.03 g per 100 g BM) in April. By contrast, the mean mass of the omasum in non-lactating adult reindeer in northern Norway was 534 g (0.83 g per 100 g BM) in September but only 205 g (0.35 g per 100 g BM p < 0.05) in late March, owing to a decrease in both tissue mass and the wet mass of the contents of the organ. The mean absorptive surface of the omasum in Svalbard reindeer was 2300 cm2 in September and 2023 cm2 in April. In Norwegian reindeer, by contrast, the absorptive surface area decreased from 2201 cm2 in September to 1181 cm2 (p < 0.05) in late March. The marked seasonal decline of omasal tissue and contents in Norwegian reindeer probably results from intake of highly digestible forage plants, including lichens, in winter. Svalbard reindeer, a non-migratory sub-species, survive eating poor quality fibrous vascular plants in winter. The absence of any marked seasonal change in the mass, total absorptive surface area or filling of the omasum in Svalbard reindeer in winter despite a substantial decline in body mass presumably reflects their need to maintain maximum absorption of nutrients, including volatile fatty acids, when feeding on such poorly fermentable forage.

The incidence of glacier surging in Svalbard: evidence from multivariate statistics

Surge-type glaciers switch between long periods of slow flow and short periods of fast flow. The spatial distribution of surge-type glaciers is markedly non-random. The clustering of surge-type glaciers in certain glaciated regions and their complete absence from other regions, suggests that environmental factors control surging. To identify factors that control surging, the relationship between surging, glacial variables and geological environment was tested using logit regression models. In the analysis we used 132 surge-type and 372 normal glaciers identified from the literature and aerial photographs in the High Arctic archipelago of Svalbard. We calculated that approximately 13% of the glaciers of Svalbard are of surge-type. In the analysis we used 13 variables collected from glacier inventories and geology maps. Variables that are significantly associated with surging in Svalbard are glacier length, surface slope and the lithology of the underlying bedrock. Multivariate analyses show that long glaciers overlying shale or mudstone with steep surface slopes have the highest probabilities of surging. Surge-type glaciers are significantly less likely to overlie rocks older than Devonian. These findings do not support Kamb's linked cavity theory of surging but lend some support to soft-bed surge theories.

Summer osmoregulatory capacity of the world's northernmost living salmonid.

Anadromous Arctic charr (Salvelinus alpinus L.) were caught on their way to and from the sea with the use of a fish trap placed in the Dieset watercourse located on the Spitsbergen Island (79 degrees 10' Northern latitude) within the high-Arctic Svalbard archipelago. When subjected to a seawater challenge test (34 parts/thousand at 4-5 degrees C), charr on their way to the sea showed only minor and temporary changes in blood plasma osmolality and Na+ and Mg2+ concentrations. The seawater tests also revealed good hypoosmoregulatory capacity for Arctic charr returning from the marine environment 4 wk later. A progressive decrease in seawater tolerance was first documented 7-11 days after their return to the freshwater habitat. Thus the Svalbard charr, being the northernmost anadromous salmonid and probably a direct descendant from the first Salvelinus immigrants to freshwater systems, undergoes a preparatory increase of hypoosmoregulatory capacity (smoltification) before entering the oceanic water bodies. Furthermore, the termination of their short annual seawater stay is probably elicited by factors controlling body systems other than osmoregulation.

Glacier hydrology in Svalbard, Norwegian high arctic

Progress in glacier hydrology has focused on temperate glaciers, although partly or wholly non-temperate glaciers are found in many parts of the world, and significant areas of former ice sheets were probably non-temperate. It has usually been assumed that drainage from non-temperate glaciers consists of relatively dilute and invariable supraglacial runoff. In this paper, the hydrology of glaciers in the High-Arctic archipelago of Svalbard is examined. Variations in the thermal regimes of glaciers, and their implications for drainage, are first addressed. Results from Svalbard concerning meltwater discharge and storage, and solute and suspended-sediment dynamics are then reviewed. In general, meltwater penetration of non-temperate ice is limited, and drainage from non-temperate glaciers in Svalbard has many of the characteristics of sub-aerial drainage. However, it would be erroneous to view this drainage simply as dilute supraglacial runoff, as significant material transport occurs in suspension and solution. Furthermore, twentieth-century climate change has probably led to changes in the thermal regimes of some Svalbard glaciers, such that relict drainage structures are sometimes observed, while meltwater yields are augmented by runoff which can be attributed to the loss of mass from glaciers. At large spatial scales, turbid plumes observed at the marine margins of polythermal ice caps indicate that meltwater can be routed subglacially through non-temperate ice.

Growth and reproduction in island and mainland populations of the vole Microtus epiroticus

The vole Microtus epiroticus was accidentally introduced from Russia to the high arctic archipelago of Svalbard between 30 and 70 years ago. Data on growth patterns were collected in the laboratory for animals originating from the unique Svalbard population and from a population in Finland, close to northern Russia. Gestation period, birth mass, litter size, and age at first reproduction were similar in both populations. Longitudinal growth data were analyzed using polynomial growth curve models. Growth was bimodal, with an early peak at 8–10 days and a later peak at 15 days. The Finnish animals differed from the Svalbard animals by a higher growth rate at 12–15 days. In the field, adult body masses were much greater on Svalbard than in Finland. This difference might have been due to a phenotypic response to the cold arctic climate. We discuss the lack of clear predictions regarding microtine adaptation to the unpredictable arctic environment, and emphasize that in terms of high reproductive rates in mammals, M. epiroticus represents an extreme case.

Why don't Svalbard reindeer migrate?

Reindeer and caribou are best known as migratory, seasonally nomadic animals; many continental populations, for example, travel between distinct summer and winter ranges which may lie hundreds of km apart. Much less is known about the movements of animals belonging to island populations. This paper describes seasonal and annual movements of wild reindeer Rangifer tarandus platyrhynchus on the high arctic archipelago of Svalbard, based on observations of nine animals captured and individually marked in Adventdalen, Spitsbergen, between 1977 and 1982. Four ear‐tagged reindeer (one male and three females) were followed extensively for between four and seven years. Five radio‐collared females were followed intensively for seven months in 1982. Svalbard reindeer seem neither to undertake long migrations nor to be nomadic within seasons like mountain reindeer or barren‐ground caribou. They appear instead to use small, traditional, seasonal home ranges more, for example, like red deer or wild sheep. This atypical behaviour is discussed in relation to the dispersion of reindeers' resources in Svalbard.