kotaroo

• dos Santos Schmidt, Thassya Christina; Slotte, Aril; Olafsdottir, Anna H.; Nøttestad, Leif; Jansen, Teunis & Jacobsen, Jan Arge [Show all 13 contributors for this article] (2023). Poleward spawning of Atlantic mackerel (Scomber scombrus) is facilitated by ocean warming but triggered by energetic constraints. ICES Journal of Marine Science. ISSN 1054-3139. 81(3), p. 600–615. doi: 10.1093/icesjms/fsad098. Full text in Research Archive
• Ma, Shuyang; Huse, Geir; Ono, Kotaro; Nash, Richard David Marriott; Sandø, Anne Britt & Nedreaas, Kjell Harald [Show all 11 contributors for this article] (2023). Recruitment regime shifts and nonstationarity are widespread phenomena in harvestable stocks experiencing pronounced climate fluctuations. Fish and Fisheries. ISSN 1467-2960. doi: 10.1111/faf.12810. Full text in Research Archive Show summary

  Methods to reliably identify jump discontinuities in biological time series and to assess the specific contribution of various covariates are rapidly progressing. Here, we took advantage of these statistical improvements as well as those seen in complementary, down-scaled climate and biogeochemical models to investigate causes of the substantial interannual variability observed in recruitment strength in hindcast analyses. This systematic meta-analysis included 23 data-rich, commercially valuable, warm- and cold-temperate stocks in the North, Norwegian and Barents Seas. Since this study focuses on recruitment strength variability, we have used the term “recruitment regime shift” to distinguish from the concept of ecosystem regime shift. The breakpoint analysis revealed that the former criterion applied to more than half of the time series, mainly with respect to North Sea stocks but also to those in the Norwegian Sea. The exploratory analysis using vcGAM indicated that 1–3 shifts per stock were real, when using five drivers spanning spawning stock biomass to large-scale climatic processes. Thus, non-stationary relationships were extensively prevalent, indicating that each stock is uniquely adapted to its locally varying conditions. Outputs from the stationary GAM resembled those from the vcGAM but not after the threshold year. In-depth case studies showed that the proxy of a given driver for the process which was to be included should be critically considered in a spatiotemporal context. Furthermore, the stock-specific uncertainty associated with the given recruitment figures as such should also be an in-built component of the model construct and thereby in the evaluation of the output.

• Durant, Joël; Holt, Rebecca Emma; Ono, Kotaro & Langangen, Øystein Ole Gahr (2023). Predatory walls may impair climate warming-associated population expansion. Ecology. ISSN 0012-9658. 104(9), p. 1–8. doi: 10.1002/ecy.4130. Full text in Research Archive Show summary

  Climate change has a profound impact on species distribution and abundanceglobally, as well as local diversity, which affects ecosystem functioning. In par-ticular, changes in population distribution and abundance may lead tochanges in trophic interactions. Although species can often shift their spatialdistribution when suitable habitats are available, it has been suggested thatpredator presence can be a constraint on climate-related distribution shifts.We test this using two well-studied and data-rich marine environments.Focusing on a pair of sympatric fishes, Atlantic haddock Melanogrammus aeglefinus and cod Gadus morhua, we study the effect of the presence andabundance of the latter on the former distribution. We found that the distribu-tion of cod and increased abundance may limit the expansion of haddock tonew areas and could consequently buffer ecosystem changes due to climatechange. Though marine species may track the rate and direction of climateshifts, our results demonstrate that the presence of predators may limit theirexpansion to thermally suitable habitats. By integrating climatic and ecologicaldata at scales that can resolve predator–prey relationships, this analysis dem-onstrates the usefulness of considering trophic interactions to gain a morecomprehensive understanding and to mitigate the effects of climate change onspecies distributions.

• Clegg, Thomas L; Fuglebakk, Edvin & Ono, Kotaro (2023). Evaluating assumptions behind design-based estimators for unreported catches. Fisheries Research. ISSN 0165-7836. 263. doi: 10.1016/j.fishres.2023.106686. Full text in Research Archive Show summary

  Understanding a fishery’s impact on the marine ecosystem requires a quantification of total catches, which include unreported catches. For recent years in Norwegian waters, unreported catches have been estimated using data collected by the Norwegian Reference Fleet, a fisher self-sampling programme that regularly gathers data on catches of all species (including unwanted bycatches and discards). In this study, we focused on the use of design-based estimators for total catches in offshore fisheries, which have previously been used to estimate discards in the Norwegian coastal gillnet fisheries. After adapting the current methodology to the data available in offshore fisheries, we explored the assumptions behind both unit- and ratio-based estimators, and the effect of ignoring the cluster sampling design. Using a jack-knife resampling method to estimate the true bias in estimates of total catches and associated variability, we found that ignoring the cluster sampling design tended to underestimate the variability, which lead to occurrences where unreported catches were statistically detected when in fact there was too much uncertainty to make such a conclusion. Further validations suggested the cluster unit estimator is not unbiased as theoretically expected due to the sampling design favouring the selection of more active vessels. We therefore concluded that the unit and ratio cluster estimators are applied and compared, as per best practices.

• Anderson, Sean C.; Bacheler, Nate; Barnett, Lewis; Berg, Casper Willestofte; Blackhart, Kristan & Bolser, Derek [Show all 47 contributors for this article] (2023). WORKSHOP ON UNAVOIDABLE SURVEY EFFORT REDUCTION 2 (WKUSER2). ICES Scientific Reports. ISSN 2618-1371. 5(13). doi: 10.17895/ices.pub.22086845.
• Ono, Kotaro; Slotte, Aril; Hølleland, Sondre Nedreås; Mackinson, Steven; Jónsson, Sigurður Þór & Jacobsen, Jan Arge [Show all 7 contributors for this article] (2022). Space-time recapture dynamics of PIT-tagged Northeast Atlantic mackerel (Scomber scombrus) reveal size-dependent migratory behaviour. Frontiers in Marine Science. ISSN 2296-7745. 9. doi: 10.3389/fmars.2022.983962. Full text in Research Archive
• Langangen, Øystein Ole Gahr; Ohlberger, Jan Philipp; Stige, Leif Christian; Patin, Rémi; Buttay, Lucie & Stenseth, Nils Christian [Show all 8 contributors for this article] (2022). Effects of early life mass mortality events on fish populations. Fish and Fisheries. ISSN 1467-2960. 24(1), p. 176–186. doi: 10.1111/faf.12718. Full text in Research Archive
• Durant, Joël; Ono, Kotaro & Langangen, Øystein Ole Gahr (2022). Empirical evidence of nonlinearity in bottom up effect in a marine predator-prey system. Biology Letters. ISSN 1744-9561. 18(11). doi: 10.1098/rsbl.2022.0309. Full text in Research Archive Show summary

  Strength of species interaction may have profound effects on population dynamics. Empirical estimates of interaction strength is often based on the assumption that the interaction strengths are constant. Barents Sea cod and capelin are two fish populations for which such interaction has been acknowledged and used, under the assumption of constant interaction strength, when studying their population dynamics. However, species interaction can often be non-linear in marine ecosystems and might profoundly change our understanding of food chains. Analysing 37 years long survey time series in the Arcto-Boreal Barents Sea with a state-space modelling framework, we demonstrate that the effect of capelin on cod is not linear but shifts depending on capelin abundance: while capelin is beneficial for cod population at high abundance, below the threshold, it becomes less important for cod. Our analysis therefore shows the importance of investigating non-linearity in species interaction and may contribute to an improved understanding on species assemblages.

• Berg, Hilde Sofie Fantoft; Clegg, Tom; Blom, Geir; Kolding, Jeppe; Ono, Kotaro & Nedreaas, Kjell Harald (2022). Discards of cod (Gadus morhua) in the Norwegian coastal fisheries: Improving past and future estimates. ICES Journal of Marine Science. ISSN 1054-3139. 79(5), p. 1548–1560. doi: 10.1093/icesjms/fsac081. Full text in Research Archive
• Kleiven, Alf Ring; Espeland, Sigurd Heiberg; Stiansen, Stian; Ono, Kotaro; Zimmermann, Fabian & Olsen, Esben Moland (2022). Technological creep masks continued decline in a lobster (Homarus gammarus) fishery over a century. Scientific Reports. ISSN 2045-2322. 12. doi: 10.1038/s41598-022-07293-2. Full text in Research Archive Show summary

  Fishery-dependent data are frequently used to inform management decisions. However, inferences about stock development based on commercial data such as Catch-Per-Unit-Effort (CPUE) can be severely biased due to a phenomenon known as technological creep, where fishing technology improves over time. Here we show how trap improvement over nine decades has driven technological creep in a European lobster (Homarus gammarus) fishery. We combined fishing data, experimental fishing with contemporary and older trap types, and information on depletion effects during fishing seasons. The resulting standardized CPUE time series indicates a 92% decline in lobster abundance between 1928 and 2019 compared to 70% if technological creep is not corrected for. Differences are most pronounced within the last 40 years when the most substantial shift in gear technology occurred: an uncorrected CPUE index suggests an 8% increase in lobster abundance during this period, while the corrected CPUE index declined by 57%. We conclude that technological creep has masked a continuous stock decline, particularly in recent decades and largely driven by the shift from one- to two-chambered traps, as well as the ability of newer trap designs to capture larger lobsters. Our study confirms the importance of adequate standardization, including technological development, when using fishery dependent CPUE for monitoring and management of data-limited fisheries.

• Ono, Kotaro; Gundersen, Sofie; Reecht, Yves & Nedreaas, Kjell Harald (2021). Estimating the status of coastal cod (Gadus morhua) north of 62˚N (ICES Subarea 2) using CPUE data from the Norwegian coastal reference fleet . In Howell, Daniel (Eds.), Arctic Fisheries Working Group (AFWG). ICES Scientific Reports 3:58. . ICES. p. 637–649.
• Ono, Kotaro; Gundersen, Sofie & Nedreaas, Kjell Harald (2021). Estimating the status of anglerfish (Lophius piscatorius) in the north of 62˚N management unit (ICES Subareas 1 and 2) using life-history ratios, length compositions, and CPUE data. In Howell, Daniel (Eds.), Arctic Fisheries Working Group (AFWG). ICES Scientific Reports 3:58. . ICES. p. 753–775.
• Berg, Casper Willestofte; Beukhof, Esther; Börjesson, Patrik; Costas, Gersom; Cunningham, Curry & Jaworski, Andrzj [Show all 16 contributors for this article] (2021). . Working group on improving survey data for analysis and advice (WGISDAA; outputs from 2020 meeting). ICES Scientific Reports. ISSN 2618-1371. doi: 10.17895/ices.pub.8250.
• Howell, Daniel; Berg, Erik; Bernreuther, Matthias; Bogstad, Bjarte; Breivik, Olav Nikolai & Chetyrkin, Anatoly [Show all 24 contributors for this article] (2021). Benchmark workshop for Barents Sea and Faroese stocks (WKBARFAR 2021). ICES Scientific Reports. ISSN 2618-1371. 3(21). doi: 10.17895/ices.pub.7920. Show summary

  WKBARFAR 2021 met online to revise the advice basis of three stocks: Northeast Arctic (NEA) cod, Norwegian coastal cod north of 62 degrees, and Faroese ling. During the course of the meeting, it was decided to split the Norwegian coastal cod into two separate stocks: a data-rich stock north of 67 degrees north, and a data-poor stock between 62 and 67 degrees north. The NEA cod received a revision to the existing Category 1 SAM (State-space Assessment Model) model, Norwegian coastal cod south will receive advice based on the “3-over-2” rule, while both Norwegian coastal cod north and Faroese ling move from Category 3 to Category 1 stocks with SAM assessments. NEA cod: A revised version of the Category 1 SAM assessment was approved for the advice basis for NEA cod. Given the use of density-dependence in estimating reference points, the benchmark was not able to revise these estimates. Tests were conducted indicating the biomass limit (Blim) remained appropriate, that the existing Harvest Control Rule (HCR) remained precautionary, and that the performance of the HCR is not expected to be substantially impacted by the revision in the assessment model. Reference points will be fully re-evaluated at a forthcoming HCR evaluation, likely in 2022. Faroese Ling: This stock will now be assessed with a Category 1 SAM model, previously the stock was Category 3 with no analytic assessment. Full reference points are estimated, although the actual management is currently based on days at sea controls. Norwegian coastal cod north of 67°N: Category 1 SAM model, the first accepted analytic assessment for this stock. Evaluation of the Spawning–stock biomass (SSB) to recruit plot indicated a continued increase in recruitment across the range of SSBs observed during the model period. Consequently, Blim is provisionally set to the highest observed SSB, with a strong recommendation to conduct further investigations and put in place a recovery plan for this stock. Without evidence of recruitment performance above Blim, no reliable estimates could be provided for F reference points. Norwegian coastal cod between 62 and 67°N: Advice for this stock will be using Category 3, with a “3-over-2” rule based on the Catch Per Unit of Effort (CPUE) index from the reference fleet, with a Length-Based Spawners Per Recruit (LBSPR) model used to indicate if a precautionary buffer is required. It is likely that a SPiCT (Production model in Continuous Time) model may be a viable future assessment method, once the reference fleet CPUE time-series has been extended sufficiently.

• Clegg, Tom; Fuglebakk, Edvin; Ono, Kotaro; Vølstad, Jon Helge & Nedreaas, Kjell Harald (2021). A simulation approach to assessing bias in a fisheries self-sampling programme. ICES Journal of Marine Science. ISSN 1054-3139. 79(1), p. 76–87. doi: 10.1093/icesjms/fsab242. Full text in Research Archive Show summary

  The hierarchical structure and non-probabilistic sampling in fisher self-sampling programmes makes it difficult to evaluate biases in total catch estimates. While so, it is possible to evaluate bias in the reported component of catches, which can then be used to infer likely bias in total catches. We assessed bias in the reported component of catches for 18 species in the Barents Sea trawl and longline fisheries by simulating 2000 realizations of the Norwegian Reference Fleet sampling programme using the mandatory catch reporting system, then for each realization we estimated fleet-wide catches using simple design-based estimators and quantified bias. We then inserted variations (e.g. simple random and systematic sampling) at different levels of the sampling design (sampling frame, vessel, and operation) to identify important factors and trends affecting bias in reported catches. We found that whilst current sampling procedures for fishing operations were not biased, non-probabilistic vessel sampling resulted in bias for some species. However, we concluded this was typically within the bounds of expected variation from probabilistic sampling. Our results highlight the risk of applying these simple estimators to all species. We recommend that future estimates of total catches consider alternative estimators and more conservative estimates of uncertainty where necessary.

• Goto, Daisuke; Devine, Jennifer Ann; Umar, Ibrahim; Fischer, Simon; Oliveira, Jose & Howell, Daniel [Show all 9 contributors for this article] (2021). Shaping sustainable harvest boundaries for marine populations despite estimation bias. Ecosphere. ISSN 2150-8925. 13(2). doi: 10.1002/ecs2.3923. Full text in Research Archive
• Lu, Yonglong; Wang, Pei; Wang, Chenchen; Zhang, Meng; Cao, Xianghui & Chen, Chunci [Show all 34 contributors for this article] (2021). Multiple pollutants stress the coastal ecosystem with climate and anthropogenic drivers. Journal of Hazardous Materials. ISSN 0304-3894. p. 1–10. doi: 10.1016/j.jhazmat.2021.127570.
• Durant, Joel Marcel; Ono, Kotaro; Stenseth, Nils Christian & Langangen, Øystein (2020). Nonlinearity in interspecific interactions in response to climate change: Cod and haddock as an example. Global Change Biology. ISSN 1354-1013. 26(10), p. 5554–5563. doi: 10.1111/gcb.15264. Full text in Research Archive
• Ono, Kotaro; Langangen, Øystein & Stenseth, Nils Christian (2019). Improving risk assessments in conservation ecology. Nature Communications. ISSN 2041-1723. 10, p. 1–7. doi: 10.1038/s41467-019-10700-4. Full text in Research Archive
• Ono, Kotaro; Knutsen, Halvor; Olsen, Esben M; Ruus, Anders; Hjermann, Dag Ø & Stenseth, Nils Chr (2019). Possible adverse impact of contaminants on Atlantic cod population dynamics in coastal ecosystems. Proceedings of the Royal Society of London. Biological Sciences. ISSN 0962-8452. 286(1908), p. 1–9. doi: 10.1098/rspb.2019.1167. Full text in Research Archive Show summary

  While many in-laboratory ecotoxicological studies have shown the adverse impact of pollutants to the fitness of an individual, direct evidence from the field on the population dynamics of wildlife animals has been lacking. Here, we provide empirical support for a negative effect of pollution on Atlantic cod (Gadus morhua) population dynamics in coastal waters of Norway by combining unique time series of juvenile cod abundance, body size, environmental concentration of toxic contaminants and a spatially structured population dynamics model. The study shows that mercury concentration might have decreased the reproductive potential of cod in the region despite the general decline in the environmental concentration of mercury, cadmium and hexachlorobenzene since the implementation of national environmental laws. However, some cod populations appeared to be more resistant to mercury pollution than others, and the strength and shape of mercury effect on cod reproductive potential was fjord-specific. Additionally, cod growth rate changed at scales smaller than fjords with a gradient related to the exposure to the open ocean and offshore cod. These spatial differences in life-history traits emphasize the importance of local adaptation in shaping the dynamics of local wildlife populations. Finally, this study highlights the possibility to mitigate pollution effects on natural populations by reducing the overall pollution level, but also reveals that pollution reduction alone is not enough to rebuild local cod populations. Cod population recovery probably requires complementary efforts on fishing regulation and habitat restoration.

• Stige, Leif Christian; Eriksen, Elena; Dalpadado, Padmini & Ono, Kotaro (2019). Direct and indirect effects of sea ice cover on major zooplankton groups and planktivorous fishes in the Barents Sea. ICES Journal of Marine Science. ISSN 1054-3139. 76, p. i24–i36. doi: 10.1093/icesjms/fsz063. Full text in Research Archive
• Kotwicki, Stan & Ono, Kotaro (2019). The effect of random and density-dependent variation in sampling efficiency on variance of abundance estimates from fishery surveys. Fish and Fisheries. ISSN 1467-2960. 20, p. 760–774. doi: 10.1111/faf.12375.
• Ono, Kotaro; Haynie, Alan C.; Hollowed, Anne Babcock; Ianelli, James N; McGilliard, Carey R & Punt, André E. (2018). Management strategy analysis for multispecies fisheries including technical interactions and human behavior in modeling management decisions and fishing. Canadian Journal of Fisheries and Aquatic Sciences. ISSN 0706-652X. 75(8), p. 1185–1202. doi: 10.1139/cjfas-2017-0135. Show summary

  A multispecies fishery management strategy evaluation (MSE) framework based on the example of the groundfish fishery in the Bering Sea and Aleutian Islands region of Alaska was used to examine the interplay between a bycatch species and three groundfish species. The study introduces a framework for a realistic multispecies fishery MSE by accounting for fleet dynamics, multispecies fishery quota allocation, and the temporal dynamics of technical interactions. The quota allocation and the fleet dynamics models were implemented using linear programming, and regression approaches were used to realistically project future users’ behavioral response to changes in the fishery. Models were calibrated and then validated using historical and out-of-sample data, respectively. The results highlight the importance of accounting for technical interactions and their inter-annual dynamics for both quota allocation and fleet dynamics to design a realistic multispecies fishery MSE (without them, the amount of lost yield increased). Particular attention should therefore be paid to understanding human behavior as well as its uncertainty and to refining approaches to incorporate this information into a multispecies fishery management strategy analysis

• Ono, Kotaro; Kotwicki, Stan; Dingsør, Gjert Endre & Johnsen, Espen (2018). Multispecies acoustic dead-zone correction and bias ratio estimates between acoustic and bottom-trawl data. ICES Journal of Marine Science. ISSN 1054-3139. 75(1), p. 361–373. doi: 10.1093/icesjms/fsx115. Show summary

  In this study, we extended the original work of Kotwicki et al. (2013. Combining bottom trawl and acoustic data to model acoustic dead zone correction and bottom trawl efficiency parameters for semipelagic species. Canadian Journal of Fisheries and Aquatic Sciences 70: 208–219) to jointly estimate the acoustic dead-zone correction, the bias ratio, and the gear efficiency for multiple species by using simultaneously collected acoustic and bottom-trawl data. The model was applied to cod (Gadus morhua) and haddock (Melanogrammus aeglefinus) in the Barents Sea and demonstrated a better or similar performance compared with a single species approach. The vertical distribution of cod and haddock was highly variable and was influenced by light level, water temperature, salinity, and depth. Temperature and sunlight were the most influential factors in this study. Increase in temperature resulted in decreasing catch and fish density in the acoustic dead zone (ADZ), while increasing sun altitude (surrogate for light level) increased the catch and fish density in the ADZ. The catch and density of haddock in the ADZ also increased at the lowest sun altitude level (shortly after midnight). Generally, the density of cod and haddock changed more rapidly in the ADZ than in the catch (from bottom to the effective fishing height) indicating the importance of modelling fish density in the ADZ. Finally, the uncorrelated variability in the annual residual variance of cod and haddock further strengthen the conclusion that species vertical distribution changes frequently and that there are probably many other unobserved environmental variables that affect them independently.

• Ono, Kotaro; Ianelli, James N; McGilliard, Carey R & Punt, André E. (2017). Integrating data from multiple surveys and accounting for spatio-temporal correlation to index the abundance of juvenile Pacific halibut in Alaska. ICES Journal of Marine Science. ISSN 1054-3139. 75(2), p. 572–584. doi: 10.1093/icesjms/fsx174. Show summary

  Survey indices of abundance are one of the main sources of information used in fish stock assessment. Many regions around the world, including the United States and Europe, develop survey protocols to aid in creating these indices. As ecosystems function as a continuum across borders, there is a need to develop a standardized framework for combining information across surveys. Such methods could help resolve differences in timing, spatial coverage, catchability, and selectivity among surveys. We present a method that uses survey data by length class. These data come from several regional surveys each with differing sampling designs, spatial and temporal coverage, and sampling gear. The method accounts for the spatio-temporal correlation structure in length-specific catch rates and occurrence, and allows for differences in catchability and selectivity among regions. The approach was applied to Pacific halibut (Hippoglossus stenolepis) in Alaska, a broadly distributed species for which there is considerable uncertainty in recent recruitment estimates. Results confirm the major recruitment event of 1987 recorded in the most recent stock assessment and also detected recruitment peaks in more recent years (1998 and 2004–2005). The signal seems to be mostly related to the Eastern Bering Sea shelf survey data. The approach introduced in this study is general and could be expanded to other regions and species where standardized survey data are collected that include extensive length and/or age measurements.

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• Ma, Shuyang; Huse, Geir; Clegg, Tom; Sandø, Anne Britt; Hjøllo, Solfrid Sætre & Ono, Kotaro [Show all 10 contributors for this article] (2023). Bridging climate, biophysical and statistical models to identify key drivers of recruitment variability of fish stocks inhabiting different North-East Atlantic ecoregions.
• Durant, Joël; Ono, Kotaro & Langangen, Øystein Ole Gahr (2023). Empirical evidence of non-linearity in the interaction between fish stocks in the Barents Sea. Show summary

  The strength of species interactions can have a significant impact on population dynamics. Empirical estimates of interaction strength are often based on the assumption that the interaction strength is constant. Several fish species interact in the Barents Sea and their population dynamics are typically modelled under the assumption of constant interaction strength. However, interactions between species are often non-linear in marine ecosystems and this could fundamentally change our understanding of food webs’ functioning. Here, we present two examples of such nonlinear interactions in the Barents Sea, between cod Gadus morhua and capelin Mallotus villosus, and between cod and haddock Melanogrammus aeglefinus. Analysis of long survey time series in the Arcto-boreal Barents Sea within a state-space modelling framework showed that the effect of capelin on cod is not linear but varies with capelin abundance. Similarly, interactions between cod and haddock have changed over the past two decades due to rising ocean temperatures, altering the equilibrium abundances and the dynamics of the system. Our analyses demonstrate that long-term climate change in the Arcto-boreal system leads to differences in equilibrium conditions for species communities and demonstrates the importance of investigating nonlinearities in species interactions, leading to a better understanding of species communities and species assemblages.

• Christensen-Dalsgaard, Signe; Layton-Matthews, Kate; Ono, Kotaro; Strøm, Hallvard; Tarroux, Arnaud & Bærum, Kim Magnus (2022). Toward a sustainable fishery in the North: The impacts of seabird bycatch on the population dynamics of threatened seabirds.
• Homrum, Eydna í; Óskarsson, Guðmundur J.; Ono, Kotaro; Hølleland, Sondre Nedreås & Slotte, Aril (2022). Changes towards stable good somatic condition and increased gonad investment of Norwegian spring-spawning herring (Clupea harengus) after 2005 are linked to extended feeding period. Frontiers in Marine Science. ISSN 2296-7745. 9. doi: 10.3389/fmars.2022.803171.
• Deininger, Anne; Martin, Angela Helen; Pardo, Juan; Berg, Paul Ragnar; Bhardwaj, Jyotirmoy & de Oliveira Catarino, Diana Sofia [Show all 15 contributors for this article] (2021). Coastal Research Seen Through an Early Career Lens—A Perspective on Barriers to Interdisciplinarity in Norway. Frontiers in Marine Science. ISSN 2296-7745. 8. doi: 10.3389/fmars.2021.634999. Full text in Research Archive
• Fall, Johanna Jennifer Elisabeth; Nedreaas, Kjell Harald; Ono, Kotaro; Otterå, Håkon Magne & Gundersen, Sofie (2024). Kartlegging av menneskelig aktivitet på utvalgte gytefelt for kysttorsk nord for 62°N. Havforskningsinstituttet. ISSN 1893-4536. Full text in Research Archive Show summary

  Formålet med denne rapporten er kartlegging av fiskeriaktivitet og annen menneskelig aktivitet på og rundt høyt verdisatte gytefelt for kysttorsk for å identifisere områder som kan egne seg som verneområder. Rapporten svarer delvis opp bestillinger vedrørende kysttorsk i tildelingsbrevet 2023 til Havforskningsinstitutet, og vil fungere som kunnskapsgrunnlag i videre arbeid med gytefeltvern i samarbeid med Fiskeridirektoratet. Hovedfokus i rapporten er kartlegging av kommersiell fiskeriaktivitet i tid og rom på lokasjonsnivå og innenfor gytefeltene, samt akvakultur og turistfiskebedrifter. Landingsdata fra kommersielle fiskerier har blitt koblet til sporingsdata så langt mulig for å kartlegge fiskeriaktivitet på selve gytefeltene. Vi gir råd om reduksjon av fiske og/eller begrensning av annen menneskelig aktivitet på selve gytefeltet og/eller på lokasjonsnivå, der datagrunnlaget tilsier dette. I de fleste lokasjoner som omtales er torskefisket konsentrert i gytetiden, og mesteparten av torsken fiskes med garn fra fartøy < 11m. Områder med størst torskefangst i gyteområdene er Kvænangen, Smørfjorden (Porsanger), Sør-Vikna, Grytøya-Vikafjorden (Vandve-Dønna), samt Revsbotn og Repparfjorden i Finnmark. Områder med størst andel torskefangst på gytfeltet (i forhold til lokasjonen som helhelt) er Borgundfjorden, Revsbotn og Repparfjorden, Kvænangen, Baljsfjorden, og Vandve-Dønna. Det er stor oppdrettsaktivitet i flere av de utvalgte områdene, og noen områder har i lang tid vært utsatt for utslipp fra industrivirksomhet (f.eks. gytefeltet Hemnes i Ranfjorden). Ved eventuelt vern av gytefelt er det viktig å vurdere tidsperiode og areal i forhold til gytevandring og gyteperiode, for å unngå at torsken fiskes på vei inn til gytefeltet.

• Glemarec, Gildas; Bærum, Kim Magnus; Kingston, Allen; Campbell, Neil; Clark, Bethany L. & Hornborg, Sara [Show all 12 contributors for this article] (2024). Workshop on seabird bycatch monitoring in the NEAFC regulatory areas (WKBB). International Council for the Exploration of the Sea (ICES). ISSN 2618-1371. 5(78). Full text in Research Archive
• Olafsdottir, Anna H.; Planque, Benjamin; Anker-Nilssen, Tycho; Arneberg, Per; Bas, Lucas Johannes & Berset, Are [Show all 40 contributors for this article] (2023). Working group on the integrated assessments of the Norwegian Sea (WGINOR, outputs from 2022 meeting). International Council for the Exploration of the Sea (ICES). ISSN 2618-1371. 5(15).
• Howell, Daniel; Nielsen, Anders; Stock, Brian; Ono, Kotaro; Clain, Laura & Fossheim, Maria [Show all 45 contributors for this article] (2023). Advice on fishing opportunities for Barents Sea capelin in 2024 — ICES subareas 1 and 2 excluding Division 2.a west of 5°W. Havforskningsinstituttet. ISSN 1502-8828. Full text in Research Archive
• Clegg, Thomas L; Blom, Geir; Ono, Kotaro & Nedreaas, Kjell Harald (2021). Estimating the size distribution of reported catches on-board factory vessels – Issues with using data from the production process. Fiskeridirektoratet. ISSN 9788292075098.
• Olsen, Erik Joel Steinar; Aanes, Sondre; Aldrin, Magne Tommy; Breivik, Olav Nikolai; Fuglebakk, Edvin & Goto, Daisuke [Show all 21 contributors for this article] (2021). Final report for the REDUS project - Reduced Uncertainty in Stock Assessment. Havforskningsinstituttet. ISSN 1893-4536. Full text in Research Archive Show summary

  The REDUS project (2016-2020) has been a strategic project at the Institute of Marine Research (IMR) aimed at quantifying and reducing the uncertainty in data-rich and age-structured stock assessments (e.g., cod, herring, haddock, capelin). Work was organized in four topical work-packages: Fisheries-dependent (catch) surveys and assessment modeling (WP1), Fishery-independent (scientific) surveys (WP2), Evaluating and testing of long-term management strategies (WP3), and Communication of uncertainty, dissemination of project results and capacity building (WP4). The Norwegian Computing Center (NR) was contracted in as a strategic partner in statistical modeling and analysis, contributing mainly to WP1 and WP2, but found the research of fundamental interest therefore also allocating internal (NR) funding to develop the statistical science base of several of the methods.

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