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norskNorges fiskerihøgskole: Recent submissions
Now showing items 81-100 of 1734
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Trade-off between drag and catch performance when designing zooplankton trawls
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-05-10)The aquaculture sector is in pursuit of sustainable and cost-effective raw materials for feed, and the copepod Calanus finmarchicus is a marine zooplankton species of commercial interest because of its high abundance in northern areas. These copepods have the potential to meet the demand for vast quantities of marine raw materials. However, the lack of an energy- and catch-efficient trawl technology ... -
Atlantic salmon type I interferon genes revisited
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-06-12)Type I interferons (IFN–I) play a pivotal role in vertebrate innate immunity against viruses. This study is an analysis of IFN-I genes in an updated version of the Atlantic salmon genome published in 2021 (version Ssal_v3.1), revealing 47 IFN-I genes in the Atlantic salmon genome. The GH1 locus of chromosome (Chr) 3 harbors 9 IFNa genes, 5 IFNb genes, 6 IFNc genes, 11 IFNe genes and 1 IFNf gene. ... -
Walking sideways? Management of the Norwegian snow crab fishery
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-05-03)The snow crab (Chionoecetes opilio) in the Barents Sea is an invasive species, first discovered in 1997. Since 2012, a commercial fishery has developed, and various management measures have been implemented. Despite fishing gear restrictions, limits for the catch season and the implementation of a TAC-regime in 2017 onwards, the fishery struggles with substantial sustainability challenges. ... -
Biodiversity Baseline of the Norwegian Coastline Using eDNA Metabarcoding
(Master thesis; Mastergradsoppgave, 2024-06-21)Using eDNA metabarcoding on sea water samples collected along the entire Norwegian coastline in collaboration with FDIR, in the three governmental management plan regions of Barents Sea-Lofoten, Norwegian Sea and North Sea-Skagerrak -
Diving into the diet of sperm whales (Physeter macrocephalus) off the northern Norwegian coast: Insights from fecal DNA metabarcoding
(Master thesis; Mastergradsoppgave, 2024-05-15)Sperm whales are elusive creatures; they spend much of their time out of sight, deep in the oceans. This makes them difficult to study, and previously, studies of their diet have mainly been stomach content analyses of stranded or caught individuals. However, DNA metabarcoding has the potential for solving this problem. This thesis examines the diet of sperm whales in the Norwegian Sea, of which we ... -
Selective Isolation of Actinobacteria from Marine Invertebrates: A Bio-Prospective Search for New Producer Strains
(Master thesis; Mastergradsoppgave, 2024-05-15)Actinobacteria are spore-forming Gram-positive bacteria, with high G-C content in their genome. Their ability to metabolize complex compounds helps them survive different environmental conditions and form diverse associations with different organisms. These characteristics make Actinobacteria good producers of natural products with useful bioactivity. However, Actinobacteria are slow growers and ... -
Klimaanalyse av lakseoppdrett med hybride løsninger ved Alsaker Fjordbruk A/S
(Master thesis; Mastergradsoppgave, 2024-05-14)Denne masteroppgaven undersøker effekten av innføring av hybride løsninger i lakseoppdrett for et norsk oppdrettsselskap, med sikte på å få en forståelse av hvordan innføringen av hybride løsninger kan påvirke klimagassutslipp. Oppgaven fokuserte spesielt på Scope 1- og Scope 2 utslipp fra Alsaker Fjordbruks aktiviteter, inkludert direkte utslipp fra oppdrettsanlegg og indirekte utslipp fra ... -
To keep or not to keep track of time in eternal sunshine? Diel activity patterns of Svalbard arthropods during polar day
(Master thesis; Mastergradsoppgave, 2024-02-15)Organisms on Earth are exposed to cyclic changes in environmental variables due to Earth’s rotation around it’s axis. As a response, many organisms adapt their behaviour in a rhythmic manner, which is often cued by 24h light-dark cycles. However, in the Arctic, traditional 24h light- dark cycle cues do not exist for long periods at the time. Arthropods play an important role in the high latitude ... -
Hvilke erfaringer og refleksjoner gjør kvinner i fiskeriorganisasjonene seg om betydningen av kjønn for rekruttering og arbeid i organisasjonene? Hvordan er prosessene i fiskeriorganisasjonene kjønnede?
(Master thesis; Mastergradsoppgave, 2023-11-14)Tematikken i denne masteroppgaven handler om kvinners underrepresentasjon i de styrende organer i organisasjonene innenfor fiskerinæringen. Formålet har vært å få innsikt i hvordan kvinner opplever å være en minoritet i faglag og salgslag, organisasjoner som til all tid har vært dominert av menn. Jeg har valgt et teoretisk perspektiv basert på kjønn, noe som har bidratt til å utforme problemstillingen ... -
Taxonomic accuracy and complementarity between bulk and eDNA metabarcoding provides an alternative to morphology for biological assessment of freshwater macroinvertebrates
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-05-16)Determining biological status of freshwater ecosystems is critical for ensuring ecosystem health and maintaining associated services to such ecosystems. Freshwater macroinvertebrates respond predictably to environmental disturbances and are widely used in biomonitoring programs. However, many freshwater species are difficult to capture and sort from debris or substrate and morphological identification ... -
Declining calcium concentration drives shifts toward smaller and less nutritious zooplankton in northern lakes
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-03-03)Zooplankton community composition of northern lakes is changing due to the interactive effects of climate change and recovery from acidification, yet limited data are available to assess these changes combined. Here, we built a database using archives of temperature, water chemistry and zooplankton data from 60 Scandinavian lakes that represent broad spatial and temporal gradients in key parameters: ... -
3D imaging shows nano- and microparticles are internalized by salmon skin and corneal epithelial cells
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-07-18)The rising problem of plastic pollution is becoming one of the major environmental issues for the world. In the ocean, plastics undergo degradation into smaller microplastics (MPs) and nanoplastics (NPs). Wild fish and farmed salmon would likely be exposed to these NPs and MPs both through skin and through skin wounds. Keratocyte cells, located in the skin epithelial layer, are scavenger cells which ... -
Exploring land use conflicts arising from economic activities andtheir impacts on local communities in the European Arctic
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-07-30)The European Arctic is commonly thought of as a pristine and homogeneous area. In reality, it is a diverse region experiencing growth relying on natural resource extraction. Despite local communities being primarily affected by industry activities, most socioeconomic impact assessments are conducted at the macro level. This study addresses this gap by examining the impacts of economic activities ... -
Insights into the nature of ichthyotoxins from the Chrysochromulina leadbeateri blooms in Northern Norwegian fjords
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-06-20)In May–June 2019, the microalga Chrysochromulina leadbeateri caused a massive fish-killing event in several fjords in Northern Norway, resulting in the largest direct impact ever on aquaculture in northern Europe due to toxic algae. Motivated by the fact that no algal toxins have previously been described from C. leadbeateri, we set out to investigate the chemical nature and toxicity of secondary ... -
Soundscape characteristics of RAS tanks holding Atlantic salmon (Salmo salar) during feeding and feed withdrawal
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-07-03)Behavioural monitoring can provide crucial information on welfare and feeding in aquaculture. Passive acoustic monitoring of behaviour can be particularly useful in recirculating aquaculture systems (RAS), as they often have turbid water that impairs visual monitoring. Currently, little is known about the sounds that make up the soundscapes in RAS tanks holding Atlantic salmon (Salmo salar). ... -
Inflammatory responses in Atlantic lumpfish (Cyclopterus lumpus L.) after intraperitoneal injection of a vaccine against Aeromonas salmonicida and Vibrio salmonicida at different water temperatures
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-07-16)Studying inflammatory responses induced by vaccination can contribute to a more detailed understanding of underlying immune mechanisms in lumpfish (Cyclopterus lumpus). Tissue samples from lumpfish intraperitoneally immunized with a divalent oil-adjuvanted vaccine (Aeromonas salmonicida and Vibrio salmonicida) at water temperatures of 5, 10, and 15°C were collected at 630 day degrees and 18 weeks ... -
Hack it with EDUCHIC! educational hackathons and interdisciplinary challenges—Definitions, principles, and pedagogical guidelines
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-04-17)Whereas hackathons are widespread within and outside academia and have been argued to be a valid pedagogical method for teaching interdisciplinarity, no detailed frameworks or methods are available for conceptualizing and organizing educational hackathons, i.e., hackathons dedicated to best achieving pedagogic objectives. This paper is dedicated to introducing EDUCational Hackathons for learning ... -
Effect on catch efficiency and bycatch by introducing an Excluder device in the trawl fishery for lesser sandeel (Ammodytes marinus)
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-07-31)Sampling of the North Sea trawl fishery for lesser sandeel (Ammodytes marinus) showed that 96% of the catch weight consisted of the target species, and experimental sea trials demonstrated that the observed small bycatch percentages of haddock (Melanogrammus aeglefinus), mackerel (Scomber scombrus) and grey gurnard (Eutrigla gurnardus) could be significantly lowered by inserting a netting-based ... -
Virus-specific antibody secreting cells reside in the peritoneal cavity and systemic immune sites of Atlantic salmon (Salmo salar) challenged intraperitoneally with salmonid alphavirus
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-05-08)The development and persistence of antibody secreting cells (ASC) after antigenic challenge remain inadequately understood in teleosts. In this study, intraperitoneal (ip) injection of Atlantic salmon (Salmo salar) with salmonid alphavirus (WtSAV3) increased the total ASC response, peaking 3–6 weeks post injection (wpi) locally in the peritoneal cavity (PerC) and in systemic lymphoid tissues, ... -
Observing fish behavior in towed fishing gear—is there an influence of artificial light?
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-08-29)Fish behavior is important to consider when developing selective fishing gear. In studies designed to investigate the size selective properties of towed fishing gears such as trawls, fish behavior is mainly documented by underwater video recordings. Because fishing gear can be operated at great depths or in other low light environments, artificial light is often required for underwater recordings. ...
