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Moe, B.

Publications and source records attributed to Moe, B..

5 recordsLinked to original sources

Multiple Introductions of Highly Pathogenic Avian Influenza Viruses into the High Arctic: Svalbard and Jan Mayen, 2022 - 2025

Between 2022 and 2025, highly pathogenic avian influenza viruses (HPAIVs) of clade 2.3.4.4b, including four distinct H5 Eurasian (EA) genotypes, were detected in wild birds and mammals in the Svalbard Archipelago and on the island of Jan Mayen. We describe their epidemiology and genomic characteristics to improve understanding of HPAIV occurrence and transmission in the High Arctic. The initial cases in 2022 occurred during summer and involved a glaucous gull (Larus hyperboreus) and great skuas (Stercorarius skua) on Svalbard and Jan Mayen, representing the first detections of HPAIVs in the High Arctic. Three HPAIV genotypes were identified: EA-2020-C (H5N1), EA-2021-AB (H5N1), and EA-2021-I (H5N5). In 2023, HPAIVs were detected in a broader range of bird species, and retrospectively in an Atlantic walrus reported by another research group (Odobenus rosmarus rosmarus). Genotypes identified in 2023 were EA-2020-C (H5N1), EA-2021-I (H5N5), and EA-2022-BB (H5N1). No cases were reported in 2024. In 2025, EA-2021-I (H5N5) was detected in Arctic foxes (Vulpes lagopus) on Svalbard, without preceding detections in wild birds. The foxes exhibited neurological symptoms, and necropsy of one individual revealed the presence of feathers in its stomach. All sequenced viruses from the Arctic foxes uniquely carried the combination of PB2-E627K and PB1-H115Q, which is associated with mammalian adaptation. The detection of multiple genotypes indicates repeated and independent introductions of HPAIVs into these regions. The co-circulation of genetically distinct virus strains in areas of high bird density further suggests that Arctic breeding grounds may facilitate local viral amplification, reassortment, and subsequent dissemination along migratory flyways, including transcontinental spread. Data summaryThe authors confirm all supporting data, code and protocols have been provided within the article or through supplementary data files. Influenza A whole genome sequences generated through this study are available under the GISAID accession numbers found in Table 1. All genome sequences and associated metadata supporting the findings of this study can be accessed through the persistent digital object identifier https://doi.org/10.55876/gis8.260211rq. O_TBL View this table: org.highwire.dtl.DTLVardef@15e1921org.highwire.dtl.DTLVardef@c3e91borg.highwire.dtl.DTLVardef@1fcfe78org.highwire.dtl.DTLVardef@a69606org.highwire.dtl.DTLVardef@c36c74_HPS_FORMAT_FIGEXP M_TBL O_FLOATNOTable 1.C_FLOATNO O_TABLECAPTIONDetections of highly pathogenic avian influenza virus (HPAIV) in wild birds and mammals sampled in the Svalbard Archipelago and on Jan Mayen from January 1st, 2022, to August 31st, 2025. C_TABLECAPTION C_TBL

microbiology↗

Diel and seasonal rhythmicity in activity and corticosterone in an Arctic migratory herbivore: A multifaceted approach

Birds that migrate from temperate areas to the Arctic to breed lose their strongest Zeitgeber of circadian organization when they cross the Arctic circle in spring: the 24h light-dark cycle. Under continuous daylight, diverse behavioural and physiological patterns have been detected in both free-ranging and laboratory animals. To better understand the evolution of plasticity in circadian clocks, it is essential to study behavioural and physiological rhythmicity in the context of a species ecology. Employing a multifaceted approach, which included wildlife cameras, accelerometers, and non-invasive sampling of hormone metabolites, we investigated activity patterns and corticosterone rhythmicity in a migratory herbivore, the barnacle goose (Branta leucopsis), during its Arctic breeding season in Svalbard. We found that females showed a combination of both ultradian and diel rhythmicity in nest recesses and sleep during incubation. In both parents, these rhythms in activity continued also during the gosling rearing period. During moult, many geese aligned activity with the tidal rhythm. Barnacle geese showed weak diel rhythmicity in excreted corticosterone metabolites. This suggests that while Arctic geese may adopt an alternative Zeitgeber during the Arctic summer to maintain a diel rhythm, ultradian rhythmicity remains essential, allowing the geese to flexibly adjust their rhythms to environmental conditions.

ecology↗

Wintering, rather than breeding, oceanic conditions contribute to declining survival in a long-distance migratory seabird

Steep declines in Arctic skua populations in the southern extent of their breeding range have been reported during the last half of the 20th century. We used 24 years of ringing and re-encounter data from the Faroe Islands, North Atlantic, to investigate if patterns in survival probabilities can be explained by large scale climatic events. Having first determined the migratory phenology and wintering regions, we estimated the effects on survival of the North Atlantic Oscillation (NAO) index during breeding and Oceanic Nino index (ONI) during the non-breeding period within a capture-mark-recapture framework. Temporal trends, and direct and time-lagged effects of the environment on annual survival were modelled. We found support for a substantial decrease in adult annual survival, from ca. 0.93 in 1985 to ca. 0.77 in 2008, and weak support for a decrease in young (1st year) survival over the duration of the study period. Furthermore, models indicated increased young survival following an El Nino winter. We suggest this time-lagged effect reflects downstream propagation of environmental conditions, particularly food availability, or a potential carry-over effect of El Nino conditions positively impacting the performance of the parents in the subsequent breeding season, leading to improved young survival prospects. While adult mortality cannot be attributed to the oceanic climate oscillations tested here; the negative trend in survival may account for the substantial population declines observed over the last decades.

ecology↗

Cross population comparison of complex migration strategies in a declining oceanic seabird

Human-driven change is impacting ecosystems globally, with consequential declines in biodiversity. Long-distance migrants are particularly susceptible as they depend on conditions over large geographical scales and are more likely to experience a greater range of pressures. One long-distance migrant that has experienced substantial declines across the North-East Atlantic is the Arctic Skua Stercorarius parasiticus however, little is known about their migratory behaviour or the routes they undertake. We used geolocators with salt-water switches to track Arctic Skuas from four breeding populations. To investigate migration strategies, we developed a Hidden Markov Model approach that used saltwater immersion data to classify stopovers and transit flights. We found that the skuas used several discrete staging areas during their south and northbound migrations with an area of apparent high marine productivity in the mid-North Atlantic being of high importance. Extensive overlap of individuals from different breeding populations occurred in staging areas, resulting in weak spatial connectivity between breeding and staging areas, further emphasizing their importance. At the population-level, variation in migration strategies was driven by individuals from Svalbard, which is declining less than the other populations tracked. Relative location of wintering areas also influenced migration strategies, with individuals migrating further spending a smaller proportion of their migration at stopovers compared to those wintering closer, and instead employed a fly-and-forage strategy. Identifying the complex non-breeding distribution, weak migratory connectivity and highly conserved migration strategies of Arctic Skuas is a vital step to link how conditions experienced during migration influences population dynamics and to prioritise future research and conservation actions.

ecology↗

Ocean-scale variation in migration schedules of a long-distance migratory seabird is fully compensated upon return to the breeding site

BackgroundMigratory birds generally have tightly scheduled annual cycles, in which delays can have carry-over effects on the timing of later events, ultimately impacting reproductive output. Whether temporal carry-over effects are more pronounced among migrations over larger distances, with tighter schedules, is a largely unexplored question. MethodsWe tracked individual Arctic Skuas Stercorarius parasiticus, a long-distance migratory seabird, from eight breeding populations between Greenland and Siberia using light-level geolocators. We tested whether migration schedules among breeding populations differ as a function of their use of seven widely divergent wintering areas across the Atlantic Ocean, Mediterranean Sea and Indian Ocean. ResultsBreeding at higher latitudes led not only to later reproduction and migration, but also faster spring migration and shorter time between return to the breeding area and clutch initiation. Wintering area was consistent within individuals among years; and more distant areas were associated with more time spent on migration and less time in the wintering areas. Skuas adjusted the period spent in the wintering area, regardless of migration distance, which buffered the variation in timing of autumn migration. Choice of wintering area had only minor effects on timing of return at the breeding area and timing of breeding and these effects were not consistent between breeding populations. ConclusionThe lack of a consistent effect of wintering area on timing of return between breeding areas indicates that individuals synchronize their arrival with others in their population despite extensive individual differences in migration strategies.

ecology↗