Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2017
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Arctic charr and European whitefish are considered to be strong competitors in lakes, with the latter usually being the superior species. However, high niche plasticity and lake morphometry may suggestively facilitate resource partitioning and coexistence between charr and whitefish. Here, we explore the trophic niche utilization (diet and habitat use) of charr and whitefish co-occurring with brown trout in the deep and oligotrophic Lake Fyresvatnet, southern Norway (59°05’N, 8°10’E). Using CPUE, stomach contents and stable isotope analyses, a distinct resource partitioning was revealed between brown trout and the other two species. Brown trout typically occupied the littoral zone, feeding on benthic invertebrates, surface insects and small-sized whitefish. In contrast, charr and whitefish were predominantly zooplanktivorous, but diverged somewhat in habitat utilization as charr shifted seasonally between the profundal and the littoral zone, whereas whitefish were found in the upper water layers (littoral and pelagic habitats). Accordingly, the stable isotope values of carbon (δ13C) reflected a pelagic orientated prey resource use for both charr and whitefish, whereas brown trout had elevated carbon and nitrogen (δ15N) signatures that reflected their benthivore and piscivore diet, respectively. The findings suggest that charr may not rely upon the profundal zone as a feeding habitat but as a refuge area, and may coexist with whitefish if a third competitive and predatory species like brown trout co-occur in the lake. The study indicates that a general high habitat plasticity of Arctic charr may be essential in the presently observed coexistence with a competitively superior fish species like whitefish, and that a third fish species like brown trout may facilitate this particular fish community structure.
Sammendrag
В рамках международного проекта по мониторингу бурого медведя на территории трехстороннего парка «Пасвик-Инари» (Россия, Норвегия, Финляндия) проведен анализ численности и структуры популяции бурого медведя на российской сторо-не в 2015 г. В работе представлены данные, полученные в результате применения двух бесконтактных методов: анализа ДНК образцов шерсти и экскрементов и мето-да использования фотоловушек. Материал собирали с помощью пяти ловушек для сбора шерсти из колючей проволоки и пахучей приманки и четырех фотоловушек модели Boskon Guard. Помимо этого проводился сбор экскрементов, а также шер- сти с линии ИТС государственной границы представителями Пограничной службы России. Всего было собрано 54 образца шерсти и 10 образцов экскрементов. На основании полученных результатов рассчитана численность медведей на иссле-дуемой территории, которая составила 20 особей: 13 особей были установлены при помощи только анализа ДНК, остальные 7 – при помощи фотоловушек. Всего определено 9 самок и 7 самцов; 13 взрослых особей, 4 второгодка и 3 сеголетка. Социальная структура включала в себя три семейные группы и 10 одиночек, из кото- рых один – возможный самец-доминант. Плотность населения медведей на иссле- дуемой территории составила 1 особь на 1000 га. Совместное применение методов сбора шерсти и экскрементов, фотоловушек, а также ГИС показало себя взаимодо- полняющим при анализе численности и структуры популяции бурого медведя.
Forfattere
N.P. Havill J. Elkinton J.C. Andersen Snorre Hagen Hannah J. Broadley G.J. Boettner A. CacconeSammendrag
The European winter moth, Operophtera brumata, is a non-native pest in the Northeastern USA causing defoliation of forest trees and crops such as apples and blueberries. This species is known to hybridize with O. bruceata, the Bruce spanworm, a native species across North America, although it is not known if there are hybrid generations beyond F1. To study winter moth population genetics and hybridization with Bruce spanworm, we developed two sets of genetic markers, single nucleotide polymorphisms (SNPs) and microsatellites, using genomic approaches. Both types of markers were validated using samples from the two species and their hybrids. We identified 1216 SNPs and 24 variable microsatellite loci. From them we developed a subset of 95 species-diagnostic SNPs and ten microsatellite loci that could be used for hybrid identification. We further validated the ten microsatellite loci by screening field collected samples of both species and putative hybrids. In addition to confirming the presence of F1 hybrids reported in previous studies, we found evidence for multi-generation asymmetric hybridization, as suggested by the occurrence of hybrid backcrosses with the winter month, but not with the Bruce spanworm. Laboratory crosses between winter moth females and Bruce spanworm males resulted in a higher proportion of viable eggs than the reciprocal cross, supporting this pattern. We discuss the possible roles of population demographics, sex chromosome genetic incompatibility, and bacterial symbionts as causes of this asymmetrical hybridization and the utility of the developed markers for future studies.
Forfattere
Ólöf Dóra Bartels Jónsdóttir Julia Schregel Snorre Hagen Camilla Tobiassen Siv Aarnes Albert ImslandSammendrag
The original version of this article unfortunately contained an error where the figure caption for Figures 3 and 4 was mixed.
Forfattere
Ólöf Dóra Bartels Jónsdóttir Julia Schregel Snorre Hagen Camilla Tobiassen Siv Aarnes Albert ImslandSammendrag
The potential for genetic contamination of stocks arising from translocation and subsequent release or escape of translocated and/or genetically mixed stocks may be a significant risk to wild populations. In this context, we undertook a population genetic survey of stocks of lumpfish (Cyclopterus lumpus) along the Norwegian coast to establish the existing genetic population structure, which will aid the development of policy of the species’ use as cleaner fish in salmonid aquaculture. This was done by using 14 microsatellite loci and 287 specimens collected at five fishing grounds, covering most of the Norwegian coastline from south to north, with additional 18 samples of first-generation reared fish from a fish farm outside Tromsø (North Norway). Overall, there was no indication of significant spatial genetic structuring or of positive correlation between geographic and genetic distance among the wild lumpfish samples. These results suggest that, should translocated individuals escape from aquaculture in Norway, this will probably have little to no impact on the genetic composition of the local fish population.
Forfattere
Hana Šillerová Vladislav Chrastný Martina Vitková Anna Francová Jan Jehlička Marissa R. Gutsch Jana Kocourková Paul Eric Aspholm Lars Ola Nilsson Tore Flatlandsmo Berglen Henning K.B. Jensen Michael KomárekSammendrag
Det er ikke registrert sammendrag
Forfattere
Paul Eric Aspholm Christopher Brodersen Even Nilsen Nikolai Terentjev Nikolai Kashulin Natalia PolykarpovaSammendrag
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......
Forfattere
Vladislav Chrastný Hana Šillerová Martina Vitková Anna Francová Jan Jehlička Jana Kocourková Paul Eric Aspholm Lars Ola Nilsson Tore Flatlandsmo Berglen Henning K.B. Jensen Michael KomárekSammendrag
After the phasing out of leaded gasoline, Pb emissions to the atmosphere dramatically decreased, and other sources became more significant. The contribution of unleaded gasoline has not been sufficiently recognized; therefore, we evaluated the impact of Pb from unleaded gasoline in a relatively pristine area in Subarctic NE Norway. The influence of different endmembers (Ni slag and concentrate from the Nikel smelter in Russia, PM10 filters, and traffic) on the overall Pb emissions was determined using various environmental samples (snow, lichens, and topsoils) and Pb isotope tracing. We found a strong relationship between Pb in snow and the Ni smelter. However, lichen samples and most of the topsoils were contaminated by Pb originating from the current use of unleaded gasoline originating from Russia. Historical leaded and recent unleaded gasoline are fully distinguishable using Pb isotopes, as unleaded gasoline is characterized by a low radiogenic composition (206Pb/207Pb = 1.098 and 208Pb/206Pb = 2.060) and remains an unneglectable source of Pb in the region.
Forfattere
Paul Eric AspholmSammendrag
Neptunelva har vært sterkt regulert i omtrent 20 år. Demningen fanger alt vann i elva, så ved sterk tapping og frost-tapping vil man kunne tørrlegge elva i lavvannsperiodene på senvinter og sommer. Elva fra demningen og ned mot sjøen indikerer at det ikke er fisk i elva nedenfor demningen. Dagens biologiske samfunn i elva er tilpasset marginal vannføring og delvis ingen vannføring i deler av året. Det er dog interessante forekomster av ulike insekter i lokaliteten. Fortsatt tapping i samme regimer som i dag vurderes til å ha ikke særlige negative konsekvenser. Ved lengre fullstendig tørrlegginger sommerstid vil det ha negative konsekvenser for biologisk mangfold.