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DTU Aqua har undersøgt bestanden af sort hummer i Limfjorden og kommer nu med anbefalinger til, hvordan fiskeriet kan forvaltes.

Nøglefiskerprojektet (2020-2022), der er finansieret af fiskeplejen, er et samarbejde mellem Dansk Amatørfiskerforening (DAFF), Dansk Fritidsfiskerforbund (DFF) og DTU Aqua. Det en det syvende projekt i træk. Disse treårige projekter har eksisteret siden 2002 og er baseret på en stor og værdifuld frivillig indsats af fritidsfiskere. Formålet med disse projekter er at registrere fiskefangsterne og derigennem få dokumenteret fiskeforekomster langs de danske kyster over en årrække. Sammenlagt repræsenterer disse syv treårige projekter den største, længstvarende og mest sammenhængende indsats der dokumenterer og registrerer fangster i garn og ruser langs de danske kyster. Projekterne bidrager, som de eneste, med en tidsseriedata om de kystnære fiskeforekomster i Danmark, da ingen officiel overvågning finder sted i de danske kystzoner. At denne registrering hviler på frivillig arbejdskraft, er en kæmpe præstation og afspejler fritidsfiskernes interesse i at følge og bevare de naturlige fiskebestande i fjorde, bugter og langs de åbne kyster. Med nøglefiskerprojektet er der blevet skabt tidsseriedata, der dækker 17 år med garn og 20 år med ruser. Redskaberne, der anvendes, er ens for alle deltagerne, positionerne er fastsatte, fiskeriet forgår efter fælles retningslinjer, og der er tilstrækkelige gentagelser over året i de fleste områder. Dette gør datasættet helt unikt, da det tillader en rumlig og tidslig sammenligning samt muligheden for at følge udviklingen af de enkelte fiskearter over tid. I og med at nøglefiskerprojektet er baseret på frivilligt arbejde fra engagerede fritidsfiskere, er det også muligt at indsamle ’prøver’ af det kystnære fiskesamfund, når der nøglefiskes. Det betyder, at der kan indsamles prøver op til tre gange om måneden adskillige steder (50-61 positioner) i indre danske farvande, langs kysterne eller inde i fjordene med garn og/eller ruser. Denne rapport præsenterer resultater for perioden 2020-2022 og sammenligner me

The small GTPase Ras plays an important role in connecting external and internal signalling cues to cell fate in eukaryotic cells. As such, the loss of RAS regulation, localisation, or expression level can drive changes in cell behaviour and fate. Post-translational modifications and expression levels are crucial to ensure Ras localisation, regulation, function, and cell fate, exemplified by RAS mutations and gene duplications that are common in many cancers. Here, we reveal that excessive production of yeast Ras2, in which the phosphorylation-regulated serine at position 225 is replaced with alanine or glutamate, leads to its mislocalisation and constitutive activation. Rather than inducing cell death, as has been widely reported to be a consequence of constitutive Ras2 signalling in yeast, the overexpression of RAS2S225A or RAS2S225E alleles leads to slow growth, a loss of respiration, reduced stress response, and a state of quiescence. These effects are mediated via cAMP/PKA signalling and transcriptional changes, suggesting that quiescence is promoted by an uncoupling of cell-cycle regulation from metabolic homeostasis. The quiescent cell fate induced by the overexpression of RAS2S225A or RAS2S225E could be rescued by the deletion of CUP9, a suppressor of the dipeptide transporter Ptr2, or the addition of peptone, implying that a loss of metabolic control, or a failure to pass a metabolic checkpoint, is central to this altered cell fate. Our data suggest that the combination of an increased RAS2 copy number and a dominant active mutation that leads to its mislocalisation can result in growth arrest and add weight to the possibility that approaches to retarget RAS signalling could be employed to develop new therapies.

A system concept for online alignment verification of millimeter-wave, corneal reflectometry is presented. The system utilizes beam scanning to generate magnitude-only reflectivity maps of the cornea at 650 GHz and compares these images to a precomputed/measured template map to confirm/reject sufficient alignment. A system utilizing five off-axis parabolic mirrors, a thin film beam splitter, and two-axis galvanometric mirror was designed, simulated, and evaluated with geometric and physical optics. Simulation results informed the construction of a demonstrator system which was tested with a reference reflector. Similarity metrics computed with the aligned template and 26 misaligned positions, distributed on a 0.5 mm x 0.5 mm x 0.5 mm mesh, demonstrated sufficient misalignment detection sensitivity in 23 out of 26 positions. The results show that positional accuracy on the order of 0.5 mm is possible using 0.462 mm wavelength radiation due to the perturbation of coupling efficiency via beam distortion and beam walk-off., Tera-Hertz Sensing

The implementation of ecosystem-based fisheries management requires knowledge on the ecological impact of fishing activities on species and their habitats – those both targeted and not targeted by fisheries. To identify whichecological impacts are key and what is known about them, SEAwise consulted stakeholders through European Advisory Councils and conducted a systematic review of the scientific literature to map the available knowledge and evidence. Specific reference was given to the bycatch of Protected, Endangered and Threatened (PET) species, benthic habitats, food webs and biodiversity, and impact from fisheries-related litter and ghost nets. At the stakeholder consultations, sharks and/or elasmobranchs, turtles, species interactions, and seals or marine mammals were identified as top ranked in at least three out of the five regions. Other terms identified by at least two Case Study regions were: seabirds, sensitive species, benthic habitats, litter, PET species, invasive species and species interactions.Relevant data were extracted from 549 retained papers. The majority of studies were conducted in the Mediterranean Sea, whereas only few papers reported on fishing impacts in the Baltic Sea (see figure below). Bony fish (teleosts) and benthos were the most studied ecosystem components in all Case Study regions, whereas marine mammals and cartilaginous fish were often studied in relation to bycatch of PET species. Out of the 549 papers, most of them were related to fishing impacts on food webs and biodiversity and benthic habitats, followed bybycatch of PET species and other fishing impact studies (not related to any task). Fewest studies were related to the impact of fisheries-related litter and ghost nets. Demersal trawls were by far the most studied gear in studies on commercial fishing impacts. For recreational fisheries, hooks and lines, in particular angling, was the most studied fishing activity. Among the items identified by the stakeholders, marine ma

An ecosystem approach to fisheries management requires the consideration of commercial species as components of an ecosystem and the acknowledgement of the links between their productivity and the surrounding environment. To provide a knowledge base for such links, SEAwise consulted stakeholders throughout Europe and conducted a systematic review of the scientific literature. The systematic review resulted in 2050 articles from the literature search that were screened for their tile and abstract. 516 of them were retained for data extraction. The majority of studies were conducted in the Baltic Sea and the North Sea, followed by the Western Waters, and with only a few dozen papers in the Mediterranean Sea. Cod and herring were the most studied species, temperature and more generally climate and hydrodynamics indicators were the main drivers investigated, and reproduction was the main productivity-related process. The output of the systematic review is a database of scientific articles organised by regions, species, environmental drivers and productivity-associated processes and where outcomes, but also spatial and time scales, analytical methods etc. are described in a standardised fashion. This database will be analysed in the coming months and used in the downstream tasks of WP3. The most frequently driver identified by stakeholders across regions was climate change followed by species interactions, cod, pollution, commercial fish/shellfish and plankton. Climate change effects on stocks through temperature and salinity are relatively well covered in the literature as are effects of plankton and species interaction. Studies of the effects of pollution do not occur frequently and as a consequence require a dedicated effort is made in SEAwise to remedy this. Species reported frequently by the stakeholders included cod, seabass, sardine, sole, crabs, flatfish, Norway lobster, octopus, shrimps, herring, sprat, anchovy, hake, new species (species increasing in abundance

This report describes the SEAwise data procedures and guidelines with the aim to increase the awareness about the data collected, processed and stored in the project, to ensure that all relevant data collected and used in the project is available in a well-documented, discoverable, standardised and easily accessible form, to give information on data quality and sampling protocols and, to clearly state the usage rights on the different data and to ensure use and handling of data is in accordance with Regulation 2016/679 of the European Parliament and of the Council on the protection of natural persons with regard to the processing of personal data and on the free movement of such data (General Data Protection Regulation, GDPR). Sharing research knowledge and data is integral to the SEAwise project and this is attained through implementing the FAIR principles, employing dedicated quality assurance processes and carefully considering ethical aspects of knowledge and data storing and sharing.

Ved at anvende et farvestof håber Fiskeplejen, at det bliver muligt at mærke skrubbeyngel i stort tal og mere effektivt end i dag, inden fiskene udsættes i Limfjorden. Det vil give bedre mulighed for at undersøge effekten af udsætningerne.

Estuaries are complex environments, which provide important nursery areas for several fish species, but anthropogenic activities as well as low salinities may affect fish reproductive potential. This study investigated spawning migrations of turbot (Scophthalmus maximus) and European flounder (Platichthys flesus) in the estuary Roskilde Fjord using acoustic telemetry. For turbot, migratory behaviour was coupled with salinity measurements to estimate likelihood of successful spawning. Turbot in the Roskilde Fjord are stocked fish, whereas the European flounder represents a naturally occurring population. Data suggested that the two species exhibited different migration behaviours towards the spawning season. The migratory behaviour of turbot indicate that turbot remained in the southern parts of the Roskilde Fjord where successful development of turbot eggs and larvae may be limited by low salinity. In contrast, the majority of European flounder migrated towards more marine waters prior to the spawning season, and only a minority of the fish remained inside the Roskilde Fjord during the spawning season. Consistent with previous studies, the present results indicate that European flounder perform partial spawning migration. Thus, European flounder may utilize a diversity of spawning areas, including the brackish waters in the Roskilde Fjord estuary as well as more marine waters with elevated salinities. Our results are important for future management of spawning areas, recruitment dynamics and selection of suitable turbot populations for stocking.

Background: West coast of Denmark used to be an important fishing area in previous decades. Fishers in the area have reported declines in local fish populations and fishing vessels have been reduced in numbers. Fishing is taking place further North, in Skagerrak, or further offshore. Such observations were also confirmed by previous scientific projects in the area. Nevertheless, stocks in the North Sea have been rebuilding and there is a question if the coastal areas will also see an increase in population sizes of important commercial species. Aims of the project: Given the situation in the area, the Vesterhavsfisk project has as a main goal to investigate important species distribution changes and evaluate potential fishing opportunities in the area. The aims of the project are to i) collate existing knowledge from previous studies in the area, ii) gather new information from 2 scientific surveys along 3 transects off the Danish west coast and one transect in Skagerrak, iii) recruit commercial fishers to conduct experimental fishing using commercial style gillnets along the same transects, iv) collect stomach contents from plaice and benthic samples to investigate feeding preferences of the species along the different transects and, v) evaluate the potential of re-establishing the area as commercially and biologically sustainable fishing grounds. Results: Commercial species were caught during the Havfisken survey, but the sizes indicate that the coastal area is mostly used by juvenile populations that are not interesting commercially. The number of fish caught during the gillnet experimental fishing were too low confirming that the area is not a viable fishing area. Stomach and benthic analyses for plaice showed differences in the feeding behaviour of the species and the faunal biodiversity from North to South. Changes in environmental conditions, like increasing temperatures closer to the shore have caused important commerci

An ecosystem approach to fisheries management requires the consideration of spatially explicit management measures and other impacts on species and the links between the distribution of fished species, their surrounding environment and productivity. Quantification of the spatial aspects of fisheries and ecology of commercially fished stocks may improve the accuracy of the predicted changes in fish productivity, fisheries yield and costs, benefits and selectivity. To provide a knowledge base for spatially explicit considerations, SEAwise consulted stakeholders throughout Europe and conducted a systematic review of the scientific literature. As a first step, engagement with relevant stakeholder groups in each Case Study identified key issues of relevance to spatial management. The input from this stakeholder consultation was supplemented by a systematic literature review with careful consideration of the objectives, search terms, inclusion/exclusion criteria, the method for data/knowledge extraction and ultimately how these data and knowledge will be used. The purpose of the task was to quantify the key drivers and pressures behind the changes occurring in commercial fish stocks and fisheries distribution that have a spatially explicit content, map the relevant existing scientific knowledge and provide input to the subsequent SEAwise tasks. The words identified by the stakeholders consulted focused on factors causing changes to the distribution of commercial fish/shellfish (climate change, MPAs, species interactions, pollution, habitats and invasive species) and fisheries (windfarms, MPAs, Marine spatial planning) as well as the other human impacts. The systematic review extracted data from 331 papers. The most frequently studied topic was the distribution of fish and the region with most papers was the North Sea with about the twice the amount of papers in each of the other regions. The most frequently studied species in the literature were cod, hake and plaice and b