Sealworm (Pseudoterranova decipiens) infection in grey seals (Halichoerus grypus), cod (Gadus morhua) and shorthorn sculpin (Myoxocephalus scorpius) in the Baltic Sea

The anisakid nematode Pseudoterranova decipiens, known as the sealworm or cod worm, can infect the flesh of several fish species. The parasite causes cosmetic problems for the fish industry and can cause abdominal discomfort if consumed by humans. There are only scattered studies on the abundance or distribution of the sealworm in fish and seals in the Baltic Sea. To remedy this situation, the extent of sealworm infection was investigated in cod (Gadus morhua) and shorthorn sculpin (Myoxocephalus scorpius) collected along the Swedish coast. A relative presence of the sealworm was also investigated in samples from grey seal (Halichoerus grypus) stomachs. Up to 100 % of the fish were infected in some of the areas. Sculpin were generally worse infected than cod, both in abundance and prevalence of parasites. General linear models showed a significant correlation between the number of seals in an area and the prevalence of sealworms in cod. There was a sharp decrease of infected fish in areas with salinity lower than 7 aEuro degrees. Even though the northern Baltic proper and the southern Bothnian Sea have a high number of grey seals, only one sealworm was found in a sculpin in that region, and none in cod. In grey seal stomachs the sealworm was only found in samples from the central Baltic proper; further north, all anisakid nematodes identified in seals were Contracaecum osculatum. The results indicate that seal presence drives the distribution in the southern parts of the Baltic and that low salinity, or some other variable which correlates with salinity, limits the distribution in the northern part

Prey consumption rates and growth of piscivorous brown trout in a subarctic watercourse

This is the peer reviewed version of the following article: Jensen, H., Amundsen, P.-A., Elliott, J.M., Bøhn, T. & Aspholm, P.E. (2006). Prey consumption rates and growth of piscivorous brown trout in a subarctic watercourse. Journal of Fish Biology, 68(3), 838-848, which has been published in final form at https://doi.org/10.1111/j.0022-1112.2006.00972.x. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.Prey consumption rates of piscivorous brown trout Salmo trutta were studied in the Pasvik watercourse, which forms the border between Norway and Russia. Estimates of food consumption in the field were similar to or slightly less than maximum values from a bioenergetic model. The piscivore diet consisted mainly of vendace Coregonus albula with a smaller number of whitefish Coregonus lavaretus. Individual brown trout had an estimated mean daily intake of c. 1·5 vendace and 0·4 whitefish, and a rapid annual growth increment of 7–8 cm year−1. The total population of brown trout >25 cm total length was estimated as 8445 individuals (0·6 individuals ha−1), giving a mean ± s.e. annual consumption of 1553880 ± 405360 vendace and 439140 ± 287130 whitefish for the whole watercourse. The rapid growth in summer of brown trout >25 cm indicated a high prey consumption rate

The EDU-ARCTIC project: Interacting for STEM across countries and curricula

EDU-ARCTIC is an open-schooling project, funded by the EU for the years 2016-2019 and managed by scientists, nature educators and computer–technologists. The main aim is to attract young people (13- 20 years old) to the natural sciences. Further, to raise awareness of how everything in nature is connected, and that STEM education therefore in part must be interdisciplinary across normal school curricula. To achieve these goals, EDU-ARCTIC uses innovative online and freely accessible tools, combined with nature expeditions. Four main modules complement each other, but can also be used independently: 1) Webinars, during which scientists conduct online lessons about their own field of expertise. The lessons come as packages with worksheets and online games. The lessons bring youth close to scientists. They can ask questions about research and conditions of scientific works. It is also a valuable tool for teachers to brush up their STEM knowledge and get inspiration for their own teaching. 2) Polarpedia, which is an online encyclopedia of scientific terms used in the webinars. The science is kept easy-to-grasp, with the aim to stimulate the pupils’ curiosity to look for more information. 3) Monitoring system, which uses citizen science and the project’s own app to record observations of meteorology and phenology. Observations are open for everybody to use in their own teachings. 4) Arctic Competitions, which is the module that has engaged the pupils the most. They submit their idea for a science project in winter, work with the project over a few months and present it in spring as an essay, a poster or a video. Teachers come up with innovative ways to fit this work into the normal curricula. A few lucky winners get to join scientists on expeditions to polar research stations. After 2.5 years, EDU-ARCTIC has engaged more than 1100 teachers and educators from 58 countries. There is a language barrier for some teachers, and it is difficult to fit webinars into the school timetable. However, the challenges are minor compared to the interdisciplinary success of having teachers meet across countries and curricula. Here we illustrate this in detail by presenting a way of interdisciplinary teaching (“the beauty of poetry and maths”) developed by one of the teachers in the project, Mr. Francisco José Gómez Senent. Starting from a single poem published in Nature, it innovatively combines mathematics, literature, history and linguistic competences. The teacher originally used it to stimulate curiosity about the aesthetic criterion in science. Science is not only about facts! The approach can be generalized to cover a wide range of curricula, and different teachers can use it in a team effort across classes

Påvisning av bjørn og andre rovdyr i reinbeitedistrikt Beahceveai/Pasvik 5A/5C

-Ved bruk av 10 hårfeller ble det påvist 5 ulike bjørn i kalvingslandet til reinbeitedistrikt 5A/5C fra 15 april til slutten av juni 2015. Det ble også observert individer og sportegn av jerv, gaupe og kongeørn i kalvingslandet. Dataene fra radio-bjeller (Telespor) og e-bjeller (Findmysheep) som ble båret av henholdsvis 20 og 100 simler, indikerte hvordan reinen brukte området og det er også at det er mulig å tolke bevegelsesmønstre og bevegelseshastigheter hos simlene i relasjon til rovdyrene. Ingen av de fem bjørnene var kjent fra området tidligere år og på den andre siden ble det ikke påvist noen av bjørnene som var kjent fra området i 2013 og 2014

Påvisning av bjørn og andre rovdyr i reinbeitedistrikt Beahceveai/Pasvik 5A/5C

-Ved bruk av 10 hårfeller ble det påvist 5 ulike bjørn i kalvingslandet til reinbeitedistrikt 5A/5C fra 15 april til slutten av juni 2015. Det ble også observert individer og sportegn av jerv, gaupe og kongeørn i kalvingslandet. Dataene fra radio-bjeller (Telespor) og e-bjeller (Findmysheep) som ble båret av henholdsvis 20 og 100 simler, indikerte hvordan reinen brukte området og det er også at det er mulig å tolke bevegelsesmønstre og bevegelseshastigheter hos simlene i relasjon til rovdyrene. Ingen av de fem bjørnene var kjent fra området tidligere år og på den andre siden ble det ikke påvist noen av bjørnene som var kjent fra området i 2013 og 2014

The importance of Arctic driftwood for interdisciplinary global change research (Short Communication / Methodological note)

The Arctic is one of the regions most sensitive to global warming, for which climate and environmental proxy archives are largely insufficient. Arctic driftwood provides a unique resource for research into the circumpolar entanglements of terrestrial, coastal and marine factors and processes – past, present, future. Here, first dendrochronological and wood anatomical insights into 639 Arctic driftwood samples are presented. Samples were collected across northern Norway (n =430) and north-western Iceland (n =209) in 2022. The overall potentials and limitations of Arctic driftwood to improve tree-ring chronologies from the boreal forest, and to reconstruct changes in sea ice extent and ocean current dynamics are discussed. Finally, the role driftwood has possibly played for Arctic settlements in the past hundreds of years is examined

Undersøkelse av forekomst av elvemusling i Grense Jakobselv

Sensommeren 2014 ble det midtre partiet av Grense Jakobselv fra Elvheim til sørenden av Lasaruskulpen undersøkt for forekomst av elvemusling. De nedre delene av Grense Jakobselv og sideelver har vært undersøkt tidligere (2003 og 2005). I disse tidligere undersøkelsene har det ikke blitt påvist elvemusling eller skall av døde muslinger. Under undersøkelsen i 22. – 23. juli 2014 ble de første elvemuslingene funnet like oppstrøms Sandvasselva. Denne undersøkelsen omfattet i alt 12 forhåndsutvalgte transekter. Disse transektene utgjorde ca. 1330 m elveløp som ble sjekket med snorkling motstrøms. I gjennomsnitt var det 5,5 meter bredde som var habitat for elvemusling disse områdene på norsk side av elva. Estimatet for undersøkt areal er 7.360 m2. I alt (inkludert Lasaruskulpen) ble det påvist 25 levende elvemusling i undersøkelsen i 2014, samt funn av 3 skall av døde elvemusling. Gjennomsnittlig tetthet er ca. 0,0034 elvemusling pr m2. Estimatet for den norske siden av denne delen blir på 72 individer nedstrøms Lasaruskulpen. Under arbeidet på norsk side ble observert noen få (6) individer over på den russiske siden av elva. Elvemuslingene er fordelt som enkelt stående individer unntatt ved sørenden av Lasaruskulpen hvor individene var konsentrert på om lag 5 m2......publishedVersio

Benthic Microbial Communities in a Seasonally Ice-Covered Sub-Arctic River (Pasvik River, Norway) Are Shaped by Site-Specific Environmental Conditions

The Pasvik River experiences chemical, physical, and biological stressors due to the direct discharges of domestic sewage from settlements located within the catchment and runoff from smelter and mine wastes. Sediments, as a natural repository of organic matter and associated contaminants, are of global concern for the possible release of pollutants in the water column, with detrimental effects on aquatic organisms. The present study was aimed at characterizing the riverine benthic microbial community and evaluating its ecological role in relation to the contamination level. Sediments were sampled along the river during two contrasting environmental periods (i.e., beginning and ongoing phases of ice melting). Microbial enzymatic activities, cell abundance, and morphological traits were evaluated, along with the phylogenetic community composition. Amplified 16S rRNA genes from bacteria were sequenced using a next-generation approach. Sediments were also analyzed for a variety of chemical features, namely particulate material characteristics and concentration of polychlorobiphenyls, polycyclic aromatic hydrocarbons, and pesticides. Riverine and brackish sites did not affect the microbial community in terms of main phylogenetic diversity (at phylum level), morphometry, enzymatic activities, and abundance. Instead, bacterial diversity in the river sediments appeared to be influenced by the micro-niche conditions, with differences in the relative abundance of selected taxa. In particular, our results highlighted the occurrence of bacterial taxa directly involved in the C, Fe, and N cycles, as well as in the degradation of organic pollutants and toxic compounds.Benthic Microbial Communities in a Seasonally Ice-Covered Sub-Arctic River (Pasvik River, Norway) Are Shaped by Site-Specific Environmental ConditionspublishedVersio

Monitoring of the Pasvik-Inari-Pechenga brown bear population in 2007 and 2011 using hair-trapping

The trans-border brown bear population of Pasvik-Inari-Pechenga (Norway-Finland-Russia) has been monitored using genetic analyses of feces collection since 2005. In addition in 2007, hair traps were systematically placed out in the area to collect hairs for genetic analysis, to more precisely determine the minimum numbers of bears. In 2011, we repeated this hair trap study, using the exact same methodology as in 2007, to make a direct comparison of the results from the two years. Brown bear DNA was detected in 68 of 88 hair samples (77%) obtained from hair traps in 2011 and for 56 of these samples, a complete DNA profile could be determined. We identified 20 different bears in 2011, 12 females and 8 males. Only one bear was found in more than one country (Norway and Russia). We detected 11 bears in Norway, 7 bears in Finland and 3 bears in Russia in 2011. Four of these 20 bears were previously unknown, all four from Finland. A comparison of the results from 2007 and 2011 showed that we detected fewer bears in hair traps in 2011 (20 bears) than in 2007 (24 bears), but this modest difference may be coincidental. However, we observed a large drop in the yield of hair samples in the traps in 2011 compared to 2007 (88 versus 196 samples). This observation may be suggestive of some reduced activity of bears within the study area in 2011. In addition, only five (21%) of the bears caught in hair traps in 2007 were recaptured in 2011, which indicates a substantial turnover of individuals and may indicate that more frequent hair trapping monitoring would be beneficial to reliably track changes in the population. Additional samples (mainly scats) collected opportunistically in the field within the Russian and Finnish parts of the study area in 2011 detected four male bears in the Finnish part that had not been detected by hair traps. No additional samples from Norway were included to this study and any comparisons between the hair-trapping and opportunistic sampling at this point remains difficult. However, the results indicate that both methods combined are currently the most feasible methods to monitor brown bear numbers in an area.publishedVersio

Monitoring of the Pasvik-Inari-Pechenga brown bear population in 2015 using hair-trapping

The trans-border brown bear population of Pasvik-Inari-Pechenga (Norway-Finland-Russia) has been monitored using genetic analyses of feces collection since 2005. In addition, in 2007 and 2011, hair traps were systematically placed out in the area to collect hairs for genetic analysis, to more precisely determine the minimum numbers of bears in the area. In 2015, we repeated this hair trap study, using the exact same methodology as in 2007 and 2011, to make a direct comparison of the results from all the 3 study years. Brown bear DNA was detected in 158 of 209 hair samples (76%) obtained from hair traps in 2015 and for 136 of these samples, a complete DNA profile could be determined. We identified 26 different bears in 2015, 17 females and 9 males. We detected 16 bears in Norway, 5 bears in Finland and 9 bears in Russia. Thirteen of these 26 bears were previously unknown, 7 were detected in Norway, 2 in Finland and 4 in Russia. A comparison to the results from 2007 and 2011 showed that we detected more bears in hair traps in 2015 (26 bears) than in 2007 (24 bears) and 2011 (20 bears). We observed an increase in the total yield of hair samples in the traps in 2015 (209 samples) compared to 2007 (196 samples) and 2011 (88 samples). Four (16%) and seven (35%) of the bears caught in hair traps in 2007 and in 2011, respectively, were also recaptured in 2015. Additional samples (scats and hair) collected opportunistically in the field within the Russian and Finnish parts of the study area in 2015 detected 4 male bears and 1 female bear in the Russian part leading to a total of 14 bears identified in Russia, of which 8 bears were detected for the first time. Additional scat and hair samples from the field in Norway were not included in our study and comparisons between the systematic hair-trapping and opportunistic sampling in the field were not performed. However, the results indicate that both methods combined are currently the optimal approach to monitor brown bear numbers in an area