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Seleksjon i snurrevad - Forsøk med M/S Båragutt, mai 2024
Full text linkDenne studien undersøker seleksjonsprosessen i snurrevadfiske med fokus på torsk og hyse under ulike forhold. I perioden 9.-22. mai 2024 ble det gjennomført fiskeforsøk på Finnmarkskysten ombord på snurrevadfartøyet MS Båragutt, utstyrt med en snurrevad med konvensjonelle firkantmaskede fiskeposer og diamantmaskeforlengelse av polyetylen. Studien hadde som mål å vurdere størrelsesseleksjonen til fisk både på havbunnen, i innhiving (på vei til overflaten) og i overflaten, samt den totale seleksjonen som skjer i snurrevaden under hele fiskeprosessen. Tre forsøkstyper (oppsett) ble utført: kontrollhal med småmasket pose, standardhal uten utløsermekanisme, og forsøk med utløsermekanisme designet for å minimere overflateseleksjon ved å slippe fisk i en småmasket pose på rundt 30 meter. Det ble målt totalt 47 348 hyser og 7 563 torsk. For hyse var 80,8 % av fangsten under minstemålet på 40 cm i kontrollhal. Størrelsesseleksjon på havbunnen reduserte undermålsfisk til 55,0 %, mens overflateseleksjon reduserte det ytterligere til 38,5 %. Seleksjonsparametere (L50 og SR) for hyse ble beregnet, og avdekket en total L50 på 41,5 cm, på havbunn var L50 på 40,5 cm og i overflate 37,2 cm. For torsk var 86,2 % av fangsten undermålsfisk i kontrollhal. Størrelsesseleksjon på bunn reduserte undermålsfisktil 61,2 % og etter seleksjon i havoverflaten ble den redusert til ytterligere 29,7 %. Resultatene tyder på at bruk av sekkeforlengelser har betydelig innvirkning på størrelsesseleksjon, spesielt ved å øke retensjonen av småfisk. Denne studien gir viktig informasjon for å forbedre størrelsesselektiv fiskepraksis og gir innsikt i virkningen av forlengelse på fiskestørrelsessammensetningen i kommersielle tråloperasjoner.Seleksjon i snurrevad - Forsøk med M/S Båragutt, mai 2024publishedVersio
Protokoll: Krav til konsekvensutredning ved planlegging av vindkraftprosjekter for å hindre forurensning av drikkevann
No full textpublishedVersio
Side-Stream Based Marine Solubles From Atlantic Cod (Gadus morhua) Modulate Appetite and Dietary Nutrient Utilization in Atlantic Salmon (Salmo salar L.) and can Replace Fish Meal
Full text linkWhitefish fisheries’ side-stream biomass is an abundant underutilized resource that can be valorized to benefit future aquaculture sustainability. Four novel ingredients based on side-streams from Atlantic cod (Gadus morhua) fileting were produced. FM-hb, a fish meal (FM), and FPH-hb, a fish protein hydrolysate based on heads (h) and backbones (b); FM-hbg, a FM based on heads, backbones, and viscera/guts (g); and FPC-g, a fish protein concentrate based on viscera preserved in formic acid. Four diets were prepared containing one of the ingredients replacing 50% of the dietary FM protein, in addition to a positive (FM10) and a negative (FM5) control. The six diets were fed to triplicate tanks with Atlantic salmon (Salmo salar L.; 113Æ 1 g) over 8 weeks. Besides general performance, gut and brain gene expression for selected hormones and key neuropeptides involved in the control of appetite and digestive processes were studied during feeding and postprandial, and possible reference levels for Atlantic salmon were established. All side-stream-added diets performed well, with no significant differences in performance and biometrics between the treatments. Some gene expression differences were observed, but no well-defined patterns emerged supporting clear dietary effects related to digestive performance or appetite. However, in the brain, a short-time upregulation of agouti-related protein-1 (agrp1), corresponded to higher cumulative feed intake (FI) for the FM10 diet supporting notions that this may be a candidate biomarker for appetite in salmon. Expression of stomach ghrelin-1 (ghrl1) was higher than ghrelin-2 (ghrl2) and membrane-bound O-acyltransferase domaincontaining 4 (mboat4), and midgut peptide YYa-2 (pyya2) and glucagon-a (gcga) were higher than peptide YYb-1 (pyyb1). A comparison showed that midgut peptide YYa-1 (pyya1), pyya2, and gcga expressions were higher than in the hindgut, which is opposite of what is found in mammals. In conclusion, this study shows that sustainable side-stream raw materials with different characteristics can partly replace high-quality commercial FMs giving similar performance.publishedVersio
Recent Recovery and Future Prospects of the Northeast Atlantic Halibut Stock
No full textDataset for "Recent Recovery and Future Prospects of the Northeast Atlantic Halibut Stock", published in ICES Journal of Marine Science, an Oxford journal.
The information deposited consists of 4 files.
The input data for the stock index and stock assessment are provided, together with the script to run the SPiCT stock assessment model and the fitted SPiCT object. The available data files contain:
1. Raw data from IMR’s coastal ecosystem survey data used to estimate the stock index.
2. The estimated stock index used as input for the stock assessment.
3. Total landings time series used as input for the stock assessment.
4. SPiCT script and model object
Morphological evidence supports splitting of species in the North Atlantic Sebastes spp. complex
Full text linkThe redfishes (genus Sebastes) are long-lived, commercial species in the North Atlantic. Excessive harvest through decades has led to a decline in the mature population of golden redfish (Sebastes norvegicus) in Norwegian waters, which is currently considered severely depleted. Accumulating genetic evidence suggests a more complex structure within this genus in the North Atlantic, which has recently inspired the hypotheses of cryptic species within S. norvegicus. Despite apparent genetic divergence between two types, they have yet to be verified morphologically. The morphology of genetically assigned fishes from Norwegian and Greenland waters was investigated using traditional morphometric methods, applying Linear Discriminant Analysis and Random Forest classification procedures to identify and evaluate the performance of descriptive characters. Combined with non-parametric meristic analysis, the results show that features such as beak length and eye diameter provide sufficient discrimination between the proposed cryptic species as well as separating them from the sympatric species S. mentella and S. viviparus. These findings support the presence of an additional redfish species in the North Atlantic, distinguishable both by morphological and genetic characters. This needs to be taken into consideration in future monitoring and management strategies for North Atlantic redfish.publishedVersio
Hazard characterization of the mycotoxins enniatins and beauvericin to identify data gaps and improve risk assessment for human health
Full text linkEnniatins (ENNs) and beauvericin (BEA) are cyclic hexadepsipeptide fungal metabolites which have demonstrated antibiotic, antimycotic, and insecticidal activities. The substantial toxic potentials of these mycotoxins are associated with their ionophoric molecular properties and relatively high lipophilicities. ENNs occur extensively in grain and grain-derived products and are considered a food safety issue by the European Food Safety Authority (EFSA). The tolerable daily intake and maximum levels for ENNs in humans and animals remain unestablished due to key toxicological and toxicokinetic data gaps, preventing full risk assessment. Aiming to find critical data gaps impeding hazard characterization and risk evaluation, this review presents a comprehensive summary of the existing information from in vitro and in vivo studies on toxicokinetic characteristics and cytotoxic, genotoxic, immunotoxic, endocrine, reproductive and developmental effects of the most prevalent ENN analogues (ENN A, A1, B, B1) and BEA. The missing information identified showed that additional studies on ENNs and BEA have to be performed before sufficient data for an in-depth hazard characterisation of these mycotoxins become available.Hazard characterization of the mycotoxins enniatins and beauvericin to identify data gaps and improve risk assessment for human healthpublishedVersio
Revisjon av indikatorer for tilstandsvurdering av miljø og økosystem i norske havområder — Gruppen for overvåking av de marine økosystemene
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Multispecies management: Species interactions and trade-offs, environmental changes and multiple pressures — Proceedings of the 19th Norwegian-Russian Symposium, Digital Meeting 4-5 June 2024, Bergen/Moscow/Murmansk/Tromsø
Full text linkThe 19th Norwegian-Russian Symposium, entitled “Multispecies management: species interactions and trade-offs, environmental changes and multiple pressures”, was held as a fully remote digital meeting 4-5 June 2024. The Symposium had participation from several Russian and Norwegian institutions and was considered very successful. Multispecies management is a key concept in ecosystem-based fishery management, with consideration of ecological processes integrated so that management of a stock is seen in conjunction with other associated (or interacted) stocks. The concept was developed in the 1980s for the North and Barents Seas. Initially the focus was on understanding and quantifying interrelations between stocks and their relations to highly variable environmental conditions, and development of multispecies and ecosystem models. A related topic is management of mixed fisheries where different stocks are caught in the same fishery and where the effort on one stock practically affects the level of bycatch of other co-caught stocks. Trade-offs associated with setting optimal harvest levels for interacting stocks is another key aspect of multispecies management. More broadly the marine ecosystems are impacted by a range of different stressors, and a major challenge presently is understanding the cumulative effects of human pressures acting on harvested stocks and marine ecosystems under recent climatic changes. This again relates to management and trade-offs across economic sectors (such as fisheries, aquaculture, petroleum, etc.). The Symposium program included 4 theme sessions with 33 presentations. The theme sessions were coordinated by the nominees from the Russian and Norwegian parties: Session 1: Predation and competition. (Tore Haug / Andrey Dolgov) Session 2: Mixed fisheries and bycatch. (Bjarte Bogstad / Konstantin Sokolov) Session 3: Pressures on environment and ecosystems. (Harald Gjøsæter / Andrei Krovnin) Session 4: Multispecies and ecosystem modelling. (Elena Eriksen / Yury Kovalev) The Proceedings contain contributions in a mixture of formats. Some contributions were based on articles already published. For these, the submissions to Proceedings only include the abstract plus a link to the electronic version of the published article. Other contributions, based on new, unpublished data and meant for discussions at the Symposium, is included in the Proceedings in the format of a standard scientific article and contain totally up to 10 printed pages including text, figures and tables. In addition, good contributions based on new data and due to be published in scientific journals in the near future are represented with an extended abstract (1-2 pages) in the Proceedings. Bergen/Moscow/Murmansk/Tromsø, January 2025 The editorspublishedVersio
Escaped farmed and wild Atlantic salmon in the river Etneelva 2024 - Results from the fjord- and river laboratory in Etne
No full textHovudfokus ved Fjord- og elvelaboratoriet i Etne er å studere miljøeffektar av naturlege og menneskeskapte prosessar og aktivitetar, og undersøke korleis desse påverkar bestandsdynamikken til dei ville bestandane i elva. I 2024 vart fiskefella i Etneelva sett i drift 2. april og registreringa pågjekk til 31. oktober. Det var noko redusert fangseffektivitet i løpet av sesongen pga. høg vassføring. I til saman ti driftsdøgn (5 % av driftstida) var fangsten i fella redusert pga. høg vassføring. Tilsvarande reduksjon i fangsteffektivitet har vi også hatt i tidlegare år med 9 driftsdøgn (4 % av driftstida) i 2023, 12 driftsdøgn (6 %) i 2022. Fyrste villaks blei registrert i veke 18 og fyrste rømling kom også i veke 18. I alt vart 3116 fiskar handtert på fella i 2024, mot 2684 fiskar i 2023, 4063 i 2022, 3746 i 2021 og 5093 i 2020. Av dei registrerte fiskane var 1495 villaks,1590 sjøaure og 29 rømte oppdrettslaks. Det vart ikkje registrert pukkellaks i Etne i 2024. I 2024 hadde 50 % av villaksen vandra opp per veke 29, to veker tidlegare enn rømlingane. Som tidlegare år dominerte storlaksen tidleg i oppvandringa, medan terten dominerte i slutten av oppvandringsforløpet. For rømlingane registrert på fella varierte storleiken frå 1,19 kg til 7,04 kg, med ei overvekt av individ på 1,0 til 3,0 kg. Skjelkontrollen stadfesta oppdrettsbakgrunn 29 av dei 31 registrerte oppdrettslaksane. To individ vart feilbestemde i fella, der éin av dei truleg er ein hybrid mellom sjøaure og laks den andre var en flerigangsgytar med uvanleg mye pigmentering. Av dei 29 registrerte rømlingane på fella, var 31 % kjønnsmodne og 69 % umodne. Gjennom uttaksfisket om hausten nedstraums fella i sone 1 og 2, vart det fanga 11 oppdrettslaksar. Av dei vart 2 (18 %) klassifiserte som modne, 9 (82 %) vart klassifiserte som umodne. Frå sportsfisket blei det rapportert inn éin oppdrettslaks nedstraums fella. Den vart bekrefta på innlevert skjelprøve. I dei resterande skjelprøvane frå sportsfisket, blei det ikkje oppdaga fleire rømlingar. I skjelmaterialet av villaks teke i fiskefella er det heller ikkje funne fleire rømlingar. Basert på registreringane i fiskefella og rapporteringar av sportsfisket i Elveguiden, er delen rømt fisk i 2024 redusert frå 1,9 % til » 0 %. Rundt ti personar var i større eller mindre grad engasjerte på fella, og Havforskingsinstituttet sitt budsjett for drifta var ca. 4 mill. kroner med tillegg på 0,5 mill. kroner frå OURO. Feltstasjonen i Etneelva framstår no antakeleg som det mest nøyaktige målepunktet i Europa for rømt oppdrettsfisk, villaks og sjøaure. Med utgangspunkt i merksemda som feltstasjonen i Etneelva har fått i forskings- og forvaltingsmiljøa, er det etablert ei referansegruppe for Fjord- og elvelaboratoriet for å bidra til kunnskapsdeling og -utvikling og sikra best mogleg utnytting av data, materiale og ressursar.Rømt og vill fisk i Etneelva 2024 — Resultat frå Fjord- og elvelaboratoriet i EtneEscaped farmed and wild Atlantic salmon in the river Etneelva 2024 - Results from the fjord- and river laboratory in EtnepublishedVersio
Samanlikning av historiske kvoteråd for lodde i Barentshavet basert på original og oppdatert konfigurasjon av framskrivingsmodell
Full text linkThe quota advice for the Barents Sea capelin stock happens in two steps: first the stock size is estimated based on a Russian-Norwegian survey in September. After that, the estimated amount of maturing capelin is used as basis for a prognosis for the spawning stock 6 months ahead in time. As part of the 2022 capelin benchmark, the configuration of the model used for the prognosis, Bifrost, was updated. In the present document, we make a comparison of quota advice for the advice years 2005-2023 based on forecasts with the updated and original model configurations. The results show that the catch advice in general would have been higher with the updated configuration, but the years with a no-fishery-advice were the same with the updated and original configuration. The comparison further showed that the changes in parameter settings of the cod consumption module in addition to the parameters set for natural capelin mortality in the autumn (1 October to 1 January) had the greatest impact on the advice. It must be noted that the model configuration is partly adapted to the current ecosystem state, so the comparison is most relevant for the most recent years. Furthermore, some parameters including the natural capelin mortality in the autumn and the proportion of immature cod in the Svalbard area will be updated each year as part of the capelin assessment, so the results of a direct comparison with historical advice is expected to change each year.Historical Barents Sea capelin quota advices compared using original and updated (2023) forecast model configurationsSamanlikning av historiske kvoteråd for lodde i Barentshavet basert på original og oppdatert konfigurasjon av framskrivingsmodellpublishedVersio