Arctic Svalbard Research Articles

Hydroclimate variability of High Arctic Svalbard during the Holocene inferred from hydrogen isotopes of leaf waxes

The response of the Arctic hydrologic cycle to global warming includes changes in precipitation patterns and moisture availability associated with variable sea ice extent and modes of atmospheric circulation. Reconstructions of past hydroclimate changes help constrain the natural range of these systems, identify the manners in which they respond to different forcing mechanisms, and reveal their connections to other components of the climate system, all of which lead to a better understanding of present and future changes. Here we examine hydroclimate changes during the Holocene in the High Arctic archipelago of Svalbard by reconstructing the isotopic composition of precipitation. We measured the hydrogen isotopic composition (δD values) of leaf wax compounds (n-alkanes; C25-C31) in a sediment core from Lake Hakluytvatnet on the island of Amsterdamøya, northwest Spitsbergen. We interpret δD values of mid-chain (C25) and long-chain (C29, C31) length n-alkanes to represent changes in the isotopic composition of lake water and precipitation over the last 12.9 ka. After deglaciation of the catchment, water supply became restricted and the lake experienced significant evaporative isotopic enrichment indicating warmer conditions from 12.8 to 7.5 ka. The isotope values suggest an increase in the delivery of moisture from warmer sub-polar air masses between 12.8 and 9.5 ka, followed by generally warm, but unstable conditions between 9.5 and 7.5 ka, possibly indicating a response to meltwater forcing. Sedimentary evidence indicates a hiatus in deposition c. 7.5–5.0 ka, likely as a result of desiccation of the lake. At c. 5.0 ka lacustrine sedimentation resumed and over the last 5 ka there was a progressive increase in the influence of polar air masses and colder conditions, which culminated in an abrupt shift to colder conditions at c. 1.8 ka. This late Holocene cooling ended c. 0.18 ka, when isotopic data indicate warmer conditions and greater influence of moisture derived from lower latitudes.

High Arctic plant phenology is determined by snowmelt patterns but duration of phenological periods is fixed: an example of periodicity

The duration of specific periods within a plant’s life cycle are critical for plant growth and performance. In the High Arctic, the start of many of these phenological periods is determined by snowmelt date, which may change in a changing climate. It has been suggested that the end of these periods during late-season are triggered by external cues, such as day length, light quality or temperature, leading to the hypothesis that earlier or later snowmelt dates will lengthen or shorten the duration of these periods, respectively, and thereby affect plant performance. We tested whether snowmelt date controls phenology and phenological period duration in High Arctic Svalbard using a melt timing gradient from natural and experimentally altered snow depths. We investigated the response of early- and late-season phenophases from both vegetative and reproductive phenological periods of eight common species. We found that all phenophases follow snowmelt patterns, irrespective of timing of occurrence, vegetative or reproductive nature. Three of four phenological period durations based on these phenophases were fixed for most species, defining the studied species as periodic. Periodicity can thus be considered an evolutionary trait leading to disadvantages compared with aperiodic species and we conclude that the mesic and heath vegetation types in Svalbard are at risk of being outcompeted by invading, aperiodic species from milder biomes.

Alkenone-based reconstructions reveal four-phase Holocene temperature evolution for High Arctic Svalbard

Situated at the crossroads of major oceanic and atmospheric circulation patterns, the Arctic is a key component of Earth's climate system. Compounded by sea-ice feedbacks, even modest shifts in the region's heat budget drive large climate responses. This is highlighted by the observed amplified response of the Arctic to global warming. Assessing the imprint and signature of underlying forcing mechanisms require paleoclimate records, allowing us to expand our knowledge beyond the short instrumental period and contextualize ongoing warming. However, such datasets are scarce and sparse in the Arctic, limiting our ability to address these issues. Here, we present two quantitative Holocene-length paleotemperature records from the High Arctic Svalbard archipelago, situated in the climatically sensitive Arctic North Atlantic. Temperature estimates are based on U37K unsaturation ratios from sediment cores of two lakes. Our data reveal a dynamic Holocene temperature evolution, with reconstructed summer lake water temperatures spanning a range of ∼6–8 °C, and characterized by four phases. The Early Holocene was marked by an early onset (∼10.5 ka cal. BP) of insolation-driven Hypsithermal conditions, likely compounded by strengthening oceanic heat transport. This warm interval was interrupted by cooling between ∼10.5–8.3 ka cal. BP that we attribute to cooling effects from the melting Northern Hemisphere ice sheets. Temperatures declined throughout the Middle Holocene, following a gradual trend that was accentuated by two cooling steps between ∼7.8–7 ka cal. BP and around ∼4.4–4.3 ka cal. BP. These transitions coincide with a strengthening influence of Arctic water and sea-ice in the adjacent Fram Strait. During the Late Holocene (past 4 ka), temperature change decoupled from the still-declining insolation, and fluctuated around comparatively cold mean conditions. By showing that Holocene Svalbard temperatures were governed by an alternation of forcings, this study improves our understanding of Arctic climate dynamics.

Morphological ontogeny, distribution and descriptive population parameters of Hermannia reticulata (Acari: Oribatida: Hermanniidae), with comments on Crotonioidea

ABSTRACTThe ontogeny is known for few species of the oribatid mite genus Hermannia (Hermanniidae). Here, we present the morphological ontogeny, distribution and some descriptive population parameters of Hermannia reticulata Thorell, 1871 collected from throughout Arctic Svalbard. All instars of Herm. reticulata are stocky, as other species of Hermannia Nicolet, 1855 for which ontogeny is known. They have gastronotal setae of similar form and ontogeny (12 pairs in the larva and 16 pairs in the nymphs and adult) and the same is true of prodorsal setae, except in Herm. reticulata the sensillus is clavate, whereas in the other species it is setiform. In Herm. reticulata, setae of the anal segment are delayed to the tritonymph as in most other studied species, whereas they first appear in the deutonymph in Herm. gibba. Studied species also differ by the number of epimeral setae in the nymphs and adult and the ontogeny of leg setae. Hermannia reticulata is a holarctic species and mainly occurs in the circumpolar region, but in Svalbard it is not common. Juveniles were as abundant as adults, but the density and stage structure varied among vegetation classes and samples, especially in rich moss tundra and bird cliff vegetation, where density was most variable. The morphological ontogeny of Herm. reticulata is compared with some other species of Crotonioidea.

Stratigraphic and geochemical expression of Barremian–Aptian global climate change in Arctic Svalbard

Significant changes in global climate and carbon cycling occurred during the Early Cretaceous. This study examines the expression of such climatic events in high-latitude Svalbard together with the stratigraphic utility of carbon-isotope stratigraphies. Isotopic analysis of fossil wood fragments (from the Rurikfjellet, Helvetiafjellet, and Carolinefjellet formations, Festningen, Spitsbergen) record a distinctive pattern including a negative isotope excursion preceding a positive event, correlatable with the global early Aptian isotope event. Our carbon-isotope profile improves the stratigraphic correlation and relative dating of the succession. We show that the upper part of the Helvetiafjellet Formation was deposited during the early Aptian, and not the late Barremian, as previously thought. Furthermore, we estimate an age for the abrupt contact of the Rurikfjellet Formation with the overlying Helvetiafjellet Formation (associated with a pulse of igneous activity) to be ca. 129 Ma or ca. 124 Ma, depending on which age model for the Early Cretaceous is used. The well-known dinosaur footprints of the Helvetiafjellet Formation at Festningen are constrained to the middle Barremian and, coupled with floral data, support a warm late Barremian prior to the Aptian carbon-isotope event. The appearance of glendonites at 655 m in the Carolinefjellet Formation is consistent with global cooling in the late Aptian–early Albian.

Biological soil crusts of Arctic Svalbard and of Livingston Island, Antarctica

Biological soil crusts (BSCs) occur in arid and semi-arid regions worldwide including the Polar Regions. They are important ecosystem engineers, and their composition and areal coverage should be understood before assessing key current functional questions such as their role in biogeochemical nutrient cycles and possible climate change scenarios. Our aim was to investigate the variability of BSCs from Arctic Svalbard and the Antarctic Island, Livingston, using vegetation surveys based on classification by functional group. An additional aim was to describe the structure of BSCs and represent a classification system that can be used in future studies to provide a fast and efficient way to define vegetation type and areal coverage. Firstly, this study demonstrates huge areas occupied by BSCs in Arctic Svalbard, with up to 90 % of soil surface covered, dominated by bryophytes and cyanobacteria, and showing an unexpectedly high variability in many areas. Livingston Island has lower percentage coverage, up to 55 %, but is dominated by lichens. Our findings show that both Polar Regions have varied BSC coverage, within the sites and between them, especially considering their harsh climates and latitudinal positions. Secondly, we have classified the BSCs of both areas into a system that describes the dominant functional groups and local geography, creating a simple scheme that allows easy identification of the prevailing vegetation type. Our results represent the first contribution to the description of BSCs based on their functional group composition in Polar Regions.

Experimental icing affects growth, mortality, and flowering in a high Arctic dwarf shrub.

Effects of climate change are predicted to be greatest at high latitudes, with more pronounced warming in winter than summer. Extreme mid‐winter warm spells and heavy rain‐on‐snow events are already increasing in frequency in the Arctic, with implications for snow‐pack and ground‐ice formation. These may in turn affect key components of Arctic ecosystems. However, the fitness consequences of extreme winter weather events for tundra plants are not well understood, especially in the high Arctic. We simulated an extreme mid‐winter rain‐on‐snow event at a field site in high Arctic Svalbard (78°N) by experimentally encasing tundra vegetation in ice. After the subsequent growing season, we measured the effects of icing on growth and fitness indices in the common tundra plant, Arctic bell‐heather (Cassiope tetragona). The suitability of this species for retrospective growth analysis enabled us to compare shoot growth in pre and postmanipulation years in icing treatment and control plants, as well as shoot survival and flowering. Plants from icing treatment plots had higher shoot mortality and lower flowering success than controls. At the individual sample level, heavily flowering plants invested less in shoot growth than nonflowering plants, while shoot growth was positively related to the degree of shoot mortality. Therefore, contrary to expectation, undamaged shoots showed enhanced growth in ice treatment plants. This suggests that following damage, aboveground resources were allocated to the few remaining undamaged meristems. The enhanced shoot growth measured in our icing treatment plants has implications for climate studies based on retrospective analyses of Cassiope. As shoot growth in this species responds positively to summer warming, it also highlights a potentially complex interaction between summer and winter conditions. By documenting strong effects of icing on growth and reproduction of a widespread tundra plant, our study contributes to an understanding of Arctic plant responses to projected changes in winter climatic conditions.

An introduction to the Mesozoic biotas of Scandinavia and its Arctic territories

Abstract The Mesozoic biotas of Scandinavia have been studied for nearly two centuries. However, the last 15 years have witnessed an explosive advance in research, most notably on the richly fossiliferous Triassic (Olenekian–Carnian) and Jurassic (Tithonian) Lagerstätten of the Norwegian Arctic Svalbard archipelago, Late Cretaceous (Campanian) Kristianstad Basin and Vomb Trough of Skåne in southern Sweden, and the UNESCO heritage site at Stevns Klint in Denmark – the latter constituting one of the most complete Cretaceous–Palaeogene (Maastrichtian–Danian) boundary sections known globally. Other internationally significant deposits include earliest (Induan) and latest Triassic (Norian–Rhaetian) strata from the Danish autonomous territory of Greenland, and the Early Jurassic (Sinemurian–Pliensbachian) to Early Cretaceous (Berriasian) rocks of southern Sweden and the Danish Baltic island of Bornholm, respectively. Marine palaeocommunities are especially well documented, and comprise prolific benthic macroinvertebrates, together with pelagic cephalopods, chondrichthyans, actinopterygians and aquatic amniotes (ichthyopterygians, sauropterygians and mosasauroids). Terrestrial plant remains (lycophytes, sphenophytes, ferns, pteridosperms, cycadophytes, bennettitaleans and ginkgoes), including exceptionally well-preserved carbonized flowers, are also world famous, and are occasionally associated with faunal traces such as temnospondyl amphibian bones and dinosaurian footprints. While this collective documented record is substantial, much still awaits discovery. Thus, Scandinavia and its Arctic territories represent some of the most exciting prospects for future insights into the spectacular history of Mesozoic life and environments.

Late Triassic capitosaurian remains from Svalbard and the palaeobiogeographical context of Scandinavian Arctic temnospondyls

Abstract The Norwegian Arctic Svalbard archipelago is famous for its prolific record of Early–Middle Triassic vertebrate fossils. These represent mainly marine amniotes, together with sharks, bony fishes and temnospondyl amphibians, the latter providing an important faunal correlate with coeval assemblages from the Danish autonomous region of Greenland. However, substantial biostratigraphical gaps exist in the Upper Triassic strata of Svalbard, which are marked by pronounced facies shifts from marine to deltaic systems and intermittent depositional hiatuses. These are accompanied by a dearth of documented vertebrate remains, a notable exception being the partial skull of the capitosaurian Capitosaurus polaris and a few isolated stereospondylian intercentra probably from the middle–late Carnian De Geerdalen Formation of Spitsbergen. Reassessment of this material, which incorporates the only undisputed capitosaurian fossil from Svalbard, indicates affinity with Cyclotosaurus , known elsewhere from the late Norian–early Rhaetian Fleming Fjord Formation of Greenland. The Scandinavian Arctic temnospondyls constituted components of sympatric assemblages that inhabited the Boreal margin of Pangaea throughout the Triassic.

Demersally drifting invertebrates from Kongsfjorden, Svalbård (Arctic Ocean)–a comparison of catches from drift-pump and drift-nets

Demersally drifting organisms were collected at Ny Alesund (Svalbard–Arctic Ocean) to study the taxon composition and relative abundances in the Arctic summer. Catch potentials of two collection devices for demersal drift were compared. A lowvolume submersible drift-pump and a drift-net unit were employed for the collection of demersally drifting biota, particularly for shallow aquatic habitats. With the exception of Appendicularia, Chaetognatha, Coelenterata, and Ctenophora, which were damaged at times, the pump catches were in good condition and sufficient for identification and quantification of less mobile fauna. A comparison of the two devices revealed that the drift-pump collected more specimens than the drift-net. However, the drift-net may have caused an underestimation of the abundances of invertebrates. No differences in identified taxon number and indices of richness, evenness and diversity were found. However, the proportion of invertebrate animals in the two devices was different for the three groups: zooplankton, macrofauna and meiofauna. At Svalbard, zooplankton, larvae of macrofauna, and meiofauna were successfully collected by the two collecting devices. However, the catchibility of the two devices in collecting various invertebrate taxa was different and, therefore, a sound ‘Device Effect’ was revealed.

Psychrobacter fjordensis sp. nov., a psychrotolerant bacterium isolated from an Arctic fjord in Svalbard

A Gram-negative, non-motile, non-spore-forming, psychrotolerant and halotolerant bacterium designated BSw21516B(T), was obtained from seawater in Kongsfjorden, a glacial fjord in the Arctic Svalbard and subjected to taxonomic analysis using a polyphasic approach. This bacterium was observed to optimally grow at 25-29°C; between at 4 and 34°C, but not at>35°C; and in the presence of 0-8% (w/v) NaCl at an optimum concentration of 2-5% (w/v) NaCl. Strain BSw21516B(T) was found to contain Ubiquinone-8 (Q-8) as a predominant respiratory lipoquinone and C18:1 ω9c and summed feature 3 (C16:1 ω7c and/or iso-C15:0 2-OH) as predominant cellular fatty acids. Phylogenetic analysis of 16S rRNA and gyrB gene sequences showed that this isolate belongs to the genus Psychrobacter and is closely related to Psychrobacter fozii LMG 21280(T), which was isolated from a sediment sample in Antarctica. DNA hybridization experiments revealed a low level of DNA-DNA relatedness (less than 58.6%) between strain BSw21516B(T) and its closest relatives. Based on these results a new species Psychrobacter fjordensis sp. nov. is proposed (type strain BSw21516B(T)=KCTC 42279(T)=CCTCC AB 2014020(T)).

Challenges of extraordinary experiences in the Arctic

AbstractThis paper presents and discusses findings from extraordinary experiences in the Arctic Svalbard. Although extensive consumer research has focused on the positive, sublime, and communal aspects of extraordinary experiences, little emphasis has been placed on the challenging aspects. By focusing on Arctic horse riding, Arctic adventure travel and dog sledding from a practice perspective, this study provides evidence that extraordinary consumption can be marked by challenges because of unrealistic expectations, troubling learning practices and connecting with others, and how one copes with tensions. We discuss how these four main types of challenges mark consumption and as such provide a nuanced interpretation compared with the positive connotations of previous research. Copyright © 2015 John Wiley & Sons, Ltd.

Landsat-8 OLI를 이용한 북극해 스발바드 피요르드의 고해상도 Ocean Color Product 산출

Ocean Color products have been used to understand marine ecosystem. In high latitude region, ice melting optically influences the ocean color products. In this study, we assessed optical properties in fjord around Svalbard Arctic sea, and estimated distribution of chlorophyll-a and suspended sediment by using high resolution satellite data, Landsat-8 Operational Land Imager (OLI). To estimate chlorophyll-a and suspended sediment concentrations, various regression models were tested with different band ratio. The regression models were not shown high correlation because of temporal difference between satellite data and in-situ data. However, model-derived distribution of ocean color products from OLI showed a possibility that fjord and coastal areas around Arctic Sea can be monitored with high resolution satellite data. To understand climate change pattern around Arctic Sea, we need to understand ice meting influences on marine ecosystem change. Results of this study will be used to high resolution monitoring of ice melting and its influences on the marine ecosystem change at high latitude. KOPRI (Korea Polar Research Institute) has been operated the Dasan station on Svalbard since 2002, and study was conducted using Arctic station.

Warmer and wetter winters: characteristics and implications of an extreme weather event in the High Arctic

One predicted consequence of global warming is an increased frequency of extreme weather events, such as heat waves, droughts, or heavy rainfalls. In parts of the Arctic, extreme warm spells and heavy rain-on-snow (ROS) events in winter are already more frequent. How these weather events impact snow-pack and permafrost characteristics is rarely documented empirically, and the implications for wildlife and society are hence far from understood. Here we characterize and document the effects of an extreme warm spell and ROS event that occurred in High Arctic Svalbard in January–February 2012, during the polar night. In this normally cold semi-desert environment, we recorded above-zero temperatures (up to 7 °C) across the entire archipelago and record-breaking precipitation, with up to 98 mm rainfall in one day (return period of >500 years prior to this event) and 272 mm over the two-week long warm spell. These precipitation amounts are equivalent to 25 and 70% respectively of the mean annual total precipitation. The extreme event caused significant increase in permafrost temperatures down to at least 5 m depth, induced slush avalanches with resultant damage to infrastructure, and left a significant ground-ice cover (∼5–20 cm thick basal ice). The ground-ice not only affected inhabitants by closing roads and airports as well as reducing mobility and thereby tourism income, but it also led to high starvation-induced mortality in all monitored populations of the wild reindeer by blocking access to the winter food source. Based on empirical-statistical downscaling of global climate models run under the moderate RCP4.5 emission scenario, we predict strong future warming with average mid-winter temperatures even approaching 0 °C, suggesting increased frequency of ROS. This will have far-reaching implications for Arctic ecosystems and societies through the changes in snow-pack and permafrost properties.

A molecular survey of freshwater microeukaryotes in an Arctic reservoir (Svalbard, 79°N) in summer by using next-generation sequencing

The molecular diversity of freshwater microeukaryotes, particularly phytoplankton, in the Arctic Svalbard, has been relatively unexplored. Freshwater algae are considered biological indicators of environmental change and can be useful in assessing the impact of global climate change and increased environmental pollution. In this study, freshwater microeukaryotes in an Arctic reservoir at Ny-Ǻlesund (Svalbard, Norway) were studied using the hypervariable V1–V3 small subunit rRNA and 454 pyrosequencing. On the basis of 8,956 reads, we revealed high genetic diversity in eukaryotes, representing all known eukaryotic supergroups, except Excavata. “Chromalveolata” (previously supergroup Chromalveolata) and Archaeplastida were the most and least abundant supergroups, respectively. After data mining, 57 phylotypes were detected from 7,398 pyrosequences. They were dominated by stramenopiles (84 %) and Dinoflagellata (13 %), with minor contributions from Cryptophyta, Chlorophyta, and Telonemida. The detection of algae belonging to the orders Mamiellales and Monomastigales provides a window into a fraction of the ‘rare biosphere’ that had previously been undetected in such environments. Interestingly, no haptophytes were recorded. Stramenopiles and Dinoflagellata mainly comprised taxa belonging to the families Chrysophyceae, Synurophyceae, and Dinophyceae. On the basis of the proportion of operational taxonomic units, the dominant phylotypes were found to include Ochromonas spp., Mallomonas spp., and Uroglena americana. These results demonstrate the significance of a chrysophyte-dominated microeukaryotic community, which is of great potential for future studies in terms of reconstruction of past climate trends and monitoring of environmental change in the Arctic.

Temperature preference of juvenile Arctic charr originating from different thermal environments

Temperature preference of juvenile (age 1+) Arctic charr (Salvelinus alpinus L.) originating from four arctic and sub-arctic populations (Svalbard and mainland northern Norway), representing a range of habitats with different temperature conditions, was studied by use of a shuttle-box system which allowed individual fish to control their environmental temperature. Based on the assumption that adaptations to long-lasting differences in thermal environments would affect temperature preference, we expected that Arctic charr from the high arctic Svalbard would prefer a lower temperature than the charr from two well-studied sub-arctic mainland lakes (i.e. one anadromous charr population from Storvatn, Hammerfest and two sympatric resident charr morphs from Fjellfrosvatn, Malselv). There were, however, no significant differences in temperature preference among the four populations after 24 h exposure to the shuttle-box system, although the charr from the omnivore upper-water sympatric morph of Fjellfrosvatn used significantly longer time to reach a stable thermal preferendum than the fish of the other populations. The average temperature preference at the end of the trials ranged between 10.9 and 11.6 °C among the populations. The lack of population differences suggests that temperature preference is not a polymorphic trait under strong selection in Arctic charr.

Seasonal differences in jump performance in the Svalbard rock ptarmigan (Lagopus muta hyperborea)

ABSTRACTFat storage is essential to the survival of many bird species, providing energy reserves, but can have an effect on locomotor performance with an associated potential increase in predation risk. In particular, the ability to initiate flight through jumping is critical to predator avoidance and may be influenced by changes in body mass (Mb). Here we investigate seasonal differences in the jump take-off performance of high Arctic Svalbard rock ptarmigan (Lagopus muta hyperborea) resulting from around a 50% increase in Mb during winter as a result of fat deposition. Using force-plate data and videography, we reveal that, in the absence of alterations to take-off angle, winter Svalbard rock ptarmigan are unable to increase hind-limb power output during jumping to compensate for their increased Mb. As a result, peak take-off velocity is reduced by 42% and jump duration is also extended during winter. The consequences of reduced jumping performance upon Svalbard ptarmigan during winter may be relatively small given their low risk of predation during this season. It may be, however, that the observed reduction in jumping performance when fat may contribute to the sub-maximal pattern of fat acquisition observed in other bird species.

A Multirelational Approach for Understanding Consumer Experiences Within Tourism

This article presents and discusses a conceptual understanding of consumer experiences as multirelational. Based on consumer research, tourism research, and the being-in-the-world ontology, we propose a multirelational approach using four core concepts wherein consumers are situated ontologically in and across (a) time, (b) context, (c) body, and (d) interaction. We explore and propose how this multirelational approach can be applied to research by discussing the conceptual and practical consequences of this approach for understanding tourists’ dynamic experiences and meaning. Consequently, the article presents an alternative approach that contributes to a broader understanding of consumer experience within tourism. This approach is illustrated with examples from consumer experiences in the arctic Svalbard.

Real-time in situ detection and quantification of bacteria in the Arctic environment

At present, there are no methods that determine the total microbial load on an abiotic substrate in real time. The utility of such a capability ranges from sterilization and medical diagnostics to the search for new microorganisms in the environment and study of their ecological niches. We report the development of a hand-held, fluorescence detection device and demonstrate its applicability to the field detection of Arctic bacteria. This technology is based on the early pioneering work of Britton Chance which elucidated the intrinsic fluorescence of a number of metabolites and protein cofactors in cells, including reduced pyridine nucleotides, cytochromes and flavins. A PDA controls the device (fluorescence excitation and data collection) and processes the multiwavelength signals to yield bacterial cell counts, including estimates of live cells, dead cells and endospores. Unlike existing methods for cell counting, this method requires no sample contact or addition of reagents. The use of this technology is demonstrated with in situ measurements of two sub-glacial microbial communities at sites in Palander and colonized surface rocks in the Bockfjord Volcanic Complex during AMASE 2008 (Arctic Mars Analog Svalbard Expedition). The total bacterial load on the interrogated sample surfaces ranged from < 20 cells/cm2 to > 109 cells/cm2.

Enterobacter cloacae with a novel variant of ACT AmpC beta-lactamase originating from glaucous gull (Larus hyperboreus) in Svalbard

We aimed at Escherichia coli and Enterobacter cloacae isolates resistant to cephalosporins and fluoroquinolones and Salmonella isolates in wild birds in Arctic Svalbard, Norway. Cloacal swabs of little auks (Alle alle, n=215) and samples of faeces of glaucous gulls (Larus hyperboreus, n=15) were examined. Inducible production of AmpC enzyme was detected in E. cloacae KW218 isolate. Sequence analysis of the 1146bp PCR product of the ampC gene from this isolate revealed 99% sequence homology with the blaACT-14 and blaACT-5 AmpC beta-lactamase genes. Four, respectively six of the identified single nucleotide polymorphisms generated amino acid substitutions in the amino acid chain. As the ampC sequence polymorphism in the investigated E. cloacae strain was identified as unique, we revealed a novel variant of the ampC beta-lactamase gene blaACT-23.