morthel

• Rømo, Grim; Åkesson, Caroline Piercey; Reiertsen, Tone Kristin; Fosse, Johanna Hol; Bøe, Cathrine Arnason & Austbø, Lars [Vis alle 16 forfattere av denne artikkelen] (2026). Highly Pathogenic Avian Influenza A (H5N1) Caused Mass Death Among Black-Legged Kittiwakes (Rissa tridactyla) in Norway, 2023. Transboundary and Emerging Diseases. ISSN 1865-1674. 2026(1). doi: 10.1155/tbed/2963364. Fulltekst i vitenarkiv
• Molværsmyr, Sindre; Arnberg, Mie Prik; Helberg, Morten; Breistøl, Arild; Christensen-Dalsgaard, Signe & Moe, Børge [Vis alle 10 forfattere av denne artikkelen] (2026). A novel non-permanent attachment method for bird-borne tracking devices using 3D-printed clamps. Journal of Ornithology. ISSN 2193-7192. 167, s. 919–930. doi: 10.1007/s10336-025-02353-6. Fulltekst i vitenarkiv Vis sammendrag

  Collecting GPS positions on bird movements requires secure and efficient attachment methods that maintain animal welfare. For seabirds, one of the most threatened bird groups globally, non-permanent attachment methods are often preferred in short-term studies due to their lower risk of injury, feather damage, or long-term behavioral disruption. However, most available non-permanent solutions, such as tape or temporary adhesives, fail to stay attached for extended periods, often resulting in device loss within days or weeks. Here, we present a novel 3D-printed clamp design for attaching small solar-powered GPS devices to seabirds. The clamp and device were attached to the bird's feathers using only glue, with the clamp specifically designed to interlock with the device. This interlocking mechanism effectively sandwiches the feathers between the clamp and the device, ensuring a secure connection through the use of glue. The clamps were designed to maximize solar panel exposure and minimize premature detachment. We deployed 86 GPS devices on six seabird species across seven locations in Norway from 2023 to 2024, using device-specific clamp variants for attachment to mantle or tail feathers. Devices remained attached for an average of 39 days on mantle feathers (77 birds) and 77 days on tail feathers (four birds), providing sufficient deployment durations to monitor key life stages, such as incubation and chick-rearing. The weight of the clamp structure ranged from 0.5 to 3.2 g, depending on the variant, and emphasis was placed on keeping the total attachment weight as low as possible. The clamps were low-cost, easy to produce using standard 3D printers, and allowed adjustments during application. Our method offers a practical alternative to conventional glue or tape mounts, enabling longer device retention, optimal solar charging, and improved data recovery without resorting to permanent attachment methods such as harnesses. It is particularly well suited for short-term tracking applications over a few weeks to months, such as studying foraging behavior, molt timing, or seasonal movements. Overall, the clamp-based attachment system offers a practical and reliable method for short-term seabird tracking, improving data quality while minimizing impact on the birds.

• Critchley, Emma Jane; Nilsson, Anna Lisa Kristina; Helberg, Morten & May, Roelof Frans (2025). Life-cycle impact assessment of offshore wind energy development on migrating bird diversity in the North Sea. Journal of Applied Ecology. ISSN 0021-8901. 62(7), s. 1597–1610. doi: 10.1111/1365-2664.70087. Fulltekst i vitenarkiv Vis sammendrag

  1.As offshore wind energy development increases, it is vital to rapidly assess the cumulative impacts to biodiversity, particularly for migratory species that could be impacted across multiple sites. Life-cycle assessments (LCAs) are a useful tool for assessing and comparing cumulative effects over a large scale and are frequently used for decision-making in industry. We have adapted the LCA methodology to assess collision, disturbance and barrier impacts of offshore wind energy developments in the North Sea on migrating birds from Norway by 2030. 2.The potentially disappeared fraction of species (PDF)—a measure of the potential loss of species richness in an area—for collision, disturbance and barrier impacts was calculated for birds on migration within migration groups, relative to wind farm energy production in GWh. Distributions were modelled based on ring recoveries from countries surrounding the North Sea Basin, using a Brownian bridge approach. 3.Wind farm developments in the North Sea were found to have the greatest impact on migrating waterbirds and soaring birds. For most groups, potential impacts from disturbance and barrier effects were higher than impacts caused by collision. Maps highlight where cumulative PDF values for combined collision, disturbance and barrier effects are expected to be highest, both by group and for all migratory species combined. 4.Synthesis and applications: Our findings stress the potential cumulative impacts to migrating birds from large-scale offshore wind energy development in the North Sea by 2030 relative to wind farm energy production. The combination of long-term bird ringing data and LCAs, which are already widely used by industry in other contexts, could be a useful tool for comparing potential impacts across proposed wind farm sites for environmental impact assessments and national strategic environmental assessments. The LCA methodology presented here could be adapted further to rapidly assess impacts of other types of energy developments on a wide range of migratory species.

• Clegg, Thomas L; Christensen-Dalsgaard, Signe; Bråthen, Vegard Sandøy; Tarroux, Arnaud; Danielsen, Jóhannis & Descamps, Sebastien [Vis alle 17 forfattere av denne artikkelen] (2024). Bycatch of northern fulmar (Fulmarus glacialis) in Norwegian longline fisheries: Assessing spatiotemporal variations in scale and risk to improve management. Global Ecology and Conservation. 56. doi: 10.1016/j.gecco.2024.e03350. Fulltekst i vitenarkiv Vis sammendrag

  Seabirds are vulnerable to bycatch in longline fisheries but for most species the impacts are largely unknown. To address this knowledge gap, studies can estimate bycatch directly using observations or calculate the theoretical risk of bycatch using overlap indexes. Here we quantify the scale and risk of bycatch of northern fulmar (Fulmarus glacialis) in the Norwegian offshore longline fishery using a ten-year time series of bycatch observations from a reference fleet programme, and large-scale datasets of fishing activity and northern fulmar distribution. We estimated an average of 0.01 (95 % CI: 0.008–0.03) northern fulmars bycaught per 1000 hooks, which results in a highly varying estimated annual bycatch of between 51 and 16242 (95 % CI) northern fulmars per year, with the largest hotspot in the Norwegian Sea during June-August. We compared these estimates with overlap indexes calculated for northern fulmars and the same fishing activity. This pinpointed the highest risk of bycatch within the breeding season, where fishing activity increased in the waters around the largest cluster of breeding colonies in the northeast Atlantic. Strong correlations between estimated bycatch and calculated overlap indexes validate overlap indexes as an indirect evaluation of risk and strengthen evidence for management decisions based on the spatial and temporal trends identified in our analyses.

• Bøe, Cathrine Arnason; Fiskebeck, Eve Marie Louise Zeyl; Reiten, Malin Rokseth; Åkerstedt, Johan; Saghafian, Maryam & Tønnessen, Ragnhild [Vis alle 15 forfattere av denne artikkelen] (2024). Emergence of highly pathogenic avian influenza viruses H5N1 and H5N5 in white-tailed eagles, 2021–2023. Journal of General Virology. ISSN 0022-1317. 105(11). doi: 10.1099/jgv.0.002035. Fulltekst i vitenarkiv Vis sammendrag

  Highly pathogenic avian influenza (HPAI) poses a substantial threat to several raptors. Between 2021 and 2023, HPAI viruses (HPAIVs) of the Goose/Guangdong lineage H5 clade 2.3.4.4b became widespread in wild birds in Norway, and H5N1 and H5N5 viruses were detected in 31 white-tailed eagles (Haliaeetus albicilla, WTEs). Post-mortem examinations of four WTEs revealed no macroscopic pathological findings. Microscopic examinations showed the presence of myocardial and splenic necroses and a few lesions in the brain. In situ hybridization revealed the presence of the virus in several organs, suggesting a multisystemic infection. The detection of HPAIV H5N5 in a WTE in February 2022 marked the first recorded occurrence of this subtype in Norway. Since then, the virus has persisted, sporadically being detected in WTEs and other wild bird species. Phylogenetic analyses reveal that at least two distinct incursions of HPAIV H5N1 Eurasian (EA) genotype C affected WTEs, likely introduced by migratory birds from Eurasia and seabirds entering from Western and Central Europe. Some WTE isolates from 2021 to 2022 clustered with those from Canada and Ireland, aligning with the transatlantic spread of H5N1. Others were related to the 2021mass mortality of great skuas in the UK or outbreaks in seabird populations, including gannets, gulls and terns, during 2022 in the North Sea region. This suggests that the WTEs were likely preying on the affected birds. Our study highlights that WTEs can act as sentinels for some HPAIV strains, but the absence of several known circulating genotypes in WTEs suggests varying pathogenic effects on this species

• Tørresen, Ole K.; Kersten, Oliver Sven; Garmann-Aarhus, Benedicte; Helberg, Morten; Tooming-Klunderud, Ave & Skage, Morten [Vis alle 8 forfattere av denne artikkelen] (2024). A chromosome-level genome assembly of the common eider, Somateria mollissima (Linnaeus, 1758). Journal of Heredity. ISSN 0022-1503. doi: 10.1093/jhered/esae042. Fulltekst i vitenarkiv Vis sammendrag

  The common eider, Somateria mollissima mollissima (Chordata; Aves; Anseriformes; Anatidae), is a large sea duck with a circumpolar distribution. We here describe a chromosome-level genome assembly from an individual female. The haplotype-resolved assembly contains one pseudo-haplotype spanning 1,205 megabases (with both Z and W sex chromosomes) and one pseudo-haplotype spanning 1,080 megabases. Most of these two assemblies (91.13% and 93.18%, respectively) are scaffolded into 32 autosomal chromosomal pseudomolecules plus Z and W for pseudo-haplotype one. The BUSCO completeness scores are 94.0% and 89.9%, respectively, and gene annotations of the assemblies identified 17,479 and 16,315 protein coding genes. Annotation of repetitive sequences classify 17.84% and 14.62% of pseudo-haplotype one and two, respectively, as repeats. The genome of the common eider will be a useful resource for the widely distributed northern species in light of climate change and anthropogenic threats.

• Brides, Kane; Thorstensen, Sverrir; Einarsson, Ólafur; Boiko, Dmitrijs; Petersen, Ævar & Auhage, Svenja N.V. [Vis alle 21 forfattere av denne artikkelen] (2023). Interchange of individuals between two Whooper Swan Cygnus cygnus populations, and its effect on population size estimates. Ringing & Migration. ISSN 0307-8698. doi: 10.1080/03078698.2022.2161004. Fulltekst i vitenarkiv
• Clark, Bethany L.; Carneiro, Ana P. B.; Pearmain, Elizabeth J.; Rouyer, Marie-Morgane; Clay, Thomas A. & Cowger, Win [Vis alle 56 forfattere av denne artikkelen] (2023). Global assessment of marine plastic exposure risk for oceanic birds. Nature Communications. 14(1). doi: 10.1038/s41467-023-38900-z. Fulltekst i vitenarkiv Vis sammendrag

  Plastic pollution is distributed patchily around the world’s oceans. Likewise, marine organisms that are vulnerable to plastic ingestion or entanglement have uneven distributions. Understanding where wildlife encounters plastic is crucial for targeting research and mitigation. Oceanic seabirds, particularly petrels, frequently ingest plastic, are highly threatened, and cover vast distances during foraging and migration. However, the spatial overlap between petrels and plastics is poorly understood. Here we combine marine plastic density estimates with individual movement data for 7137 birds of 77 petrel species to estimate relative exposure risk. We identify high exposure risk areas in the Mediterranean and Black seas, and the northeast Pacific, northwest Pacific, South Atlantic and southwest Indian oceans. Plastic exposure risk varies greatly among species and populations, and between breeding and non-breeding seasons. Exposure risk is disproportionately high for Threatened species. Outside the Mediterranean and Black seas, exposure risk is highest in the high seas and Exclusive Economic Zones (EEZs) of the USA, Japan, and the UK. Birds generally had higher plastic exposure risk outside the EEZ of the country where they breed. We identify conservation and research priorities, and highlight that international collaboration is key to addressing the impacts of marine plastic on wide-ranging species.

• Keilen, Ellen Kristine; Borgå, Katrine; Thorstensen, Helene Skjeie; Hylland, Ketil; Helberg, Morten & Warner, Nicholas Alexander [Vis alle 9 forfattere av denne artikkelen] (2022). Differences in Trophic Level, Contaminant Load, and DNA Damage in an Urban and a Remote Herring Gull (Larus argentatus) Breeding Colony in Coastal Norway. Environmental Toxicology and Chemistry. ISSN 0730-7268. 41(10), s. 2466–2478. doi: 10.1002/etc.5441. Fulltekst i vitenarkiv Vis sammendrag

  Herring gulls (Larus argentatus) are opportunistic feeders, resulting in contaminant exposure depending on area and habitat. We compared contaminant concentrations and dietary markers between two herring gull breeding colonies with different distances to extensive human activity and presumed contaminant exposure from the local marine diet. Furthermore, we investigated the integrity of DNA in white blood cells and sensitivity to oxidative stress. We analyzed blood from 15 herring gulls from each colony—the urban Oslofjord near the Norwegian capital Oslo in the temperate region and the remote Hornøya island in northern Norway, on the Barents Sea coast. Based on d13C and d34S, the dietary sources of urban gulls differed, with some individuals having a marine and others a more terrestrial dietary signal. All remote gulls had a marine dietary signal and higher relative trophic level than the urban marine feeding gulls. Concentrations (mean ± standard deviation [SD]) of most persistent organic pollutants, such as polychlorinated biphenyl ethers (PCBs) and perfluorooctane sulfonic acid (PFOS), were higher in urban marine (PCB153 17 ± 17 ng/g wet weight, PFOS 25 ± 21 ng/g wet wt) than urban terrestrial feeders (PCB153 3.7 ± 2.4 ng/g wet wt, PFOS 6.7 ± 10 ng/g wet wt). Despite feeding at a higher trophic level (d15N), the remote gulls (PCB153 17 ± 1221 ng/g wet wt, PFOS 19 ± 1421 ng/g wet wt) were similar to the urban marine feeders. Cyclic volatile methyl siloxanes were detected in only a few gulls, except for decamethylcyclopentasiloxane in the urban colony, which was found in 12 of 13 gulls. Only hexachlorobenzene was present in higher concentrations in the remote (2.6 ± 0.42 ng/g wet wt) compared with the urban colony (0.34 ± 0.33 ng/g wet wt). Baseline and induced DNA damage (doublestreak breaks) was higher in urban than in remote gulls for both terrestrial and marine feeders.

• Dietz, Rune; Fort, Jérôme; Sonne, Christian; Albert, Céline; Bustnes, Jan Ove & Christensen, Thomas Kjær [Vis alle 40 forfattere av denne artikkelen] (2021). A risk assessment of the effects of mercury on Baltic Sea, Greater North Sea and North Atlantic wildlife, fish and bivalves. Environment International. ISSN 0160-4120. 146. doi: 10.1016/j.envint.2020.106178. Fulltekst i vitenarkiv Vis sammendrag

  A wide range of species, including marine mammals, seabirds, birds of prey, fish and bivalves, were investigated for potential population health risks resulting from contemporary (post 2000) mercury (Hg) exposure, using novel risk thresholds based on literature and de novo contamination data. The main geographic focus is on the Baltic Sea, while data from the same species in adjacent waters, such as the Greater North Sea and North Atlantic, were included for comparative purposes. For marine mammals, 23% of the groups, each composing individuals of a specific sex and maturity from the same species in a specific study region, showed Hg-concentrations within the High Risk Category (HRC) and Severe Risk Category (SRC). The corresponding percentages for seabirds, fish and bivalves were 2.7%, 25% and 8.0%, respectively, although fish and bivalves were not represented in the SRC.

• Dupuis, Benjamin; Amelineau, Francoise; Tarroux, Arnaud; Bjørnstad, Oskar; Bråthen, Vegard Sandøy & Danielsen, Jóhannis [Vis alle 18 forfattere av denne artikkelen] (2021). Light-level geolocators reveal spatial variations in interactions between northern fulmars and fisheries. Marine Ecology Progress Series. ISSN 0171-8630. 676, s. 159–172. doi: 10.3354/meps13673. Fulltekst i vitenarkiv Vis sammendrag

  Seabird-fishery interactions are a common phenomenon of conservation concern. Here, we highlight how light-level geolocators provide promising opportunities to study these interactions. By examining raw light data, it is possible to detect encounters with artificial lights at night, while conductivity data give insight on seabird behaviour during encounters. We used geolocator data from 336 northern fulmars Fulmarus glacialis tracked from 12 colonies in the North-East Atlantic and Barents Sea during the non-breeding season to (1) confirm that detections of artificial lights correspond to encounters with fishing vessels by comparing overlap between fishing effort and both the position of detections and the activity of birds during encounters, (2) assess spatial differences in the number of encounters among wintering areas and (3) test whether some individuals forage around fishing vessels more often than others. Most (88.1%) of the tracks encountered artificial light at least once, with 9.5 ± 0.4 (SE) detections on average per 6 mo non-breeding season. Encounters occurred more frequently where fishing effort was high, and birds from some colonies had higher probabilities of encountering lights at night. During encounters, fulmars spent more time foraging and less time resting, strongly suggesting that artificial lights reflect the activity of birds around fishing vessels. Inter-individual variability in the probability of encountering light was high (range: 0-68 encounters per 6 mo non-breeding season), meaning that some individuals were more often associated with fishing vessels than others, independently of their colony of origin. Our study highlights the potential of geolocators to study seabird-fishery interactions at a large scale and a low cost.

• Amelineau, Francoise; Merkel, Benjamin; Tarroux, Arnaud; Descamps, Sebastien; Anker-Nilssen, Tycho & Bjørnstad, Oskar Kenneth [Vis alle 41 forfattere av denne artikkelen] (2021). Six pelagic seabird species of the North Atlantic engage in a fly-and-forage strategy during their migratory movements. Marine Ecology Progress Series. ISSN 0171-8630. 676, s. 127–144. doi: 10.3354/meps13872. Fulltekst i vitenarkiv Vis sammendrag

  Bird migration is commonly defined as a seasonal movement between breeding and non-breeding grounds. It generally involves relatively straight and directed large-scale movements, with a latitudinal change, and specific daily activity patterns comprising less or no foraging and more traveling time. Our main objective was to describe how this general definition applies to seabirds. We investigated migration characteristics of 6 pelagic seabird species (little auk Alle alle, Atlantic puffin Fratercula arctica, common guillemot Uria aalge, Brünnich’s guillemot U. lomvia, black-legged kittiwake Rissa tridactyla and northern fulmars Fulmarus glacialis). We analysed an extensive geolocator positional and saltwater immersion dataset from 29 colonies in the North-East Atlantic and across several years (2008-2019). We used a novel method to identify active migration periods based on segmentation of time series of track characteristics (latitude, longitude, net-squared displacement). Additionally, we used the saltwater immersion data of geolocators to infer bird activity. We found that the 6 species had, on average, 3 to 4 migration periods and 2 to 3 distinct stationary areas during the non-breeding season. On average, seabirds spent the winter at lower latitudes than their breeding colonies and followed specific migration routes rather than non-directionally dispersing from their colonies. Differences in daily activity patterns were small between migratory and stationary periods, suggesting that all species continued to forage and rest while migrating, engaging in a ‘fly-and-forage’ migratory strategy. We thereby demonstrate the importance of habitats visited during seabird migrations as those that are not just flown over, but which may be important for re-fuelling.

• Fauchald, Per; Tarroux, Arnaud; Amelineau, Francoise; Bråthen, Vegard Sandøy; Descamps, Sebastien & Ekker, Morten [Vis alle 40 forfattere av denne artikkelen] (2021). Year-round distribution of Northeast Atlantic seabird populations: applications for population management and marine spatial planning. Marine Ecology Progress Series. ISSN 0171-8630. 676, s. 255–276. doi: 10.3354/meps13854. Fulltekst i vitenarkiv Vis sammendrag

  Site fidelity is driven by predictable resource distributions in time and space. However, intrinsic factors related to an individual’s physiology and life-history traits can contribute to consistent foraging behaviour and movement patterns. Using 11 yr of continuous geolocation tracking data (fall 2008 to spring 2019), we investigated spatiotemporal consistency in non-breeding movements in a pelagic seabird population of black-legged kittiwakes Rissa tridactyla breeding in the High Arctic (Svalbard). Our objective was to assess the relative importance of spatial versus temporal repeatability behind inter-annual movement consistency during winter. Most kittiwakes used pelagic regions of the western North Atlantic. Winter site fidelity was high both within and across individuals and at meso (100-1000 km) and macro scales (>1000 km). Spatial consistency in non-breeding movement was higher within than among individuals, suggesting that site fidelity might emerge from individuals’ memory to return to locations with predictable resource availability. Consistency was also stronger in space than in time, suggesting that it was driven by consistent resource pulses that may vary in time more so than in space. Nonetheless, some individuals displayed more flexibility by adopting a strategy of itinerancy during winter, and the causes of this flexibility are unclear. Specialization for key wintering areas can indicate vulnerability to environmental perturbations, with winter survival and carry-over effects arising from winter conditions as potential drivers of population dynamics. Spatial distribution · Individual consistency · Migration · Repeatability · Nearest neighbor distance · Biologging · Global Location Sensors · GLS

• Knudtzon, Nina C; Thorstensen, Helene; Ruus, Anders; Helberg, Morten; Bæk, Kine & Enge, Ellen Katrin [Vis alle 7 forfattere av denne artikkelen] (2021). Maternal transfer and occurrence of siloxanes, chlorinated paraffins, metals, PFAS and legacy POPs in herring gulls (Larus argentatus) of different urban influence. Environment International. ISSN 0160-4120. 152. doi: 10.1016/j.envint.2021.106478. Fulltekst i vitenarkiv Vis sammendrag

  Urban herring gulls (Larus argentatus) are exposed to contaminants from aquatic, terrestrial and anthropogenic sources. We aim to assess if differences in urbanisation affect ecological niche and contaminant concentrations in female herring gulls. Furthermore, we investigated maternal transfer from mothers to eggs for all the target compounds, including chlorinated paraffins (CPs) and cyclic volatile methyl siloxane (cVMSs), which to our knowledge have not been assessed in herring gulls previously. We compare concentrations of legacy and emerging contaminants and metals in blood and eggs between two herring gull colonies located 51 km apart, in the urban influenced Norwegian Oslofjord. While both colonies are within an urbanised area, the inner fjord is more so, as it is surrounded by Oslo, the capital and largest city in Norway Stable isotopes of carbon and nitrogen indicated a more marine ecological niche in the outer than the inner fjord colony, although with overlap. Persistent organic pollutant (POP) concentrations were similar in the inner and outer fjord colonies, while the short-chained chlorinated paraffins (SCCP), which are recently added to the Stockholm convention and contaminants of emerging concern (CECs) varied, with higher concentrations of SCCP and the cVMS decamethylcyclopentasiloxane (D5) in females and eggs of the inner fjord colony. Per- and polyfluorinated substances (PFAS) concentrations were higher in the outer fjord colony, likely linked to releases from a point-source (airport and waste management facility with open access to food waste). In blood, chlorinated paraffins contributed most the total lipophilic contaminants (inner: 78%, outer: 56%), while polychlorinated biphenyls (PCBs) were the most abundant lipophilic contaminants in eggs (inner: 62%, outer: 46%). Dechloranes and brominated flame retardants (BFRs) were detected in few samples. Maternal transfer, assessed by egg to blood ratios, of cVMSs were similar to the POPs with mean log ratio 0.39 (D5), while it was lower for SCCPs, with log ratios-0.77. Our results indicate comparable POP exposure of the herring gulls in the inner and outer Oslofjord, likely due to overlap in ecological niches between the colonies and wide distribution of POPs. The differences between the colonies in concentrations of PFAS, cVMS and CPs shows that point source exposures and urban influence may be more important than ecological niche for these compounds.

• Thorstensen, Helene; Ruus, Anders; Helberg, Morten; Bæk, Kine; Enge, Ellen Katrin & Borgå, Katrine (2020). Common Eider and Herring Gull as Contaminant Indicators of Different Ecological Niches of an Urban Fjord System. Integrated Environmental Assessment and Management (IEAM). ISSN 1551-3777. 17(2), s. 422–433. doi: 10.1002/ieam.4340. Fulltekst i vitenarkiv Vis sammendrag

  Seabirds like gulls are common indicators in contaminant monitoring. The herring gull (Larus argentatus) is a generalist with a broad range of dietary sources, possibly introducing a weakness in its representativeness of aquatic contamination. To investigate the herring gull as an indicator of contamination in an urban‐influenced fjord, the Norwegian Oslofjord, we compared concentrations of a range of lipophilic and protein‐associated organohalogen contaminants (OHCs), Hg, and dietary markers in blood (n = 15), and eggs (n = 15) between the herring gull and the strict marine‐feeding common eider (Somateria mollissima) in the breeding period of May 2017. Dietary markers showed that the herring gull was less representative of the marine food web than the common eider. We found higher concentrations of lipophilic OHCs (wet weight and lipid weight) and Hg (dry weight) in the blood of common eider (mean ± SE ∑PCB = 210 ± 126 ng/g ww, 60 600 ± 28 300 ng/g lw; mean Hg = 4.94 ± 0.438 ng/g dw) than of the herring gull (mean ± SE ∑PCB = 19.0 ± 15.6 ng/g ww, 1210 ± 1510 ng/g lw; mean Hg = 4.26 ± 0.438 ng/g dw). Eggs gave opposite results; higher wet weight and lipid weight OHC concentrations in the herring gull (mean ± SE ∑PCB = 257 ± 203 ng/g ww, 3240 ± 2610 ng/g lw) than the common eider (mean ± SE ∑PCB = 18.2 ± 20.8 ng/g ww, 101 ± 121 ng/g lw), resulting in higher OHC maternal transfer ratios in gulls than eiders. We suggest that the matrix differences are due to fasting during incubation in the common eider. We suggest that in urban areas, herring gull might not be representative as an indicator of marine contamination but rather urban contaminant exposure. The common eider is a better indicator of marine pollution in the Oslofjord. The results are influenced by the matrix choice, as breeding strategy affects lipid dynamics regarding the transfer of lipids and contaminants to eggs and remobilization of contaminants from lipids to blood during incubation, when blood is drawn from the mother. Our results illustrate the benefit of a multispecies approach for a thorough picture of contaminant status in urban marine ecosystems. Integr Environ Assess Manag 2020;00:1–12. © 2020 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC)

• Bustnes, Jan Ove; Bårdsen, Bård-Jørgen & Helberg, Morten (2020). Lesser Black-backed Gulls (Larus fuscus fuscus) were studied over 10 breeding seasons (2005-2014) to assess factors influencing nesting distribution among 7 subcolonies with two distinct habitats (open-rocky or vegetated) in an archipelago on the Norwegian Coast. The study was divided into an early (2005-2008) and late period (2009-2014), depending on a predatory event in 2008, where one subcolony suffered a complete reproductive failure. In the early period, three open-rocky subcolonies in the. Waterbirds (De Leon Springs, Fla.). ISSN 1524-4695. 43(2), s. 163–173. doi: 10.1675/063.043.0204. Fulltekst i vitenarkiv Vis sammendrag

  Lesser Black-backed Gulls (Larus fuscus fuscus) were studied over 10 breeding seasons (2005-2014) to assess factors influencing nesting distribution among 7 subcolonies with two distinct habitats (open-rocky or vegetated) in an archipelago on the Norwegian Coast. The study was divided into an early (2005-2008) and late period (2009-2014), depending on a predatory event in 2008, where one subcolony suffered a complete reproductive failure. In the early period, three open-rocky subcolonies in the periphery appeared to contain birds of higher quality (assessed by stability in number of pairs among years, reproductive timing, clutch size, and chick production) compared to a large vegetated subcolony. In the late period, the proportion of the population nesting in the large vegetated subcolony increased, as did the quality of individuals, a result of birds from the depredated subcolony settling there. In subcolonies not subject to complete reproductive failure, philopatry to natal subcolonies was high among juveniles (∼80%), and the rate of among-year change between subcolonies by adult breeders was as low as 0-3%, although the rate of change increased up to ∼15% following years of poor reproductive success. However, there was no evidence that either habitat consistently offered better nest protection and reproductive success than the other.

• Nilsson, Anna; Slagsvold, Tore; Røstad, Ole Wiggo; Knudsen, Endre; Jerstad, Kurt & Cadahia, Luis [Vis alle 10 forfattere av denne artikkelen] (2019). Territory location and quality, together with climate, affect the timing of breeding in the white-throated dipper. Scientific Reports. 9, s. 1–11. doi: 10.1038/s41598-019-43792-5. Fulltekst i vitenarkiv Vis sammendrag

  Recent climate change has led to advanced spring phenology in many temperate regions. The phenological response to variation in the local environment, such as the habitat characteristics of the territories birds occupy, is less clear. The aim of this study is to understand how ecological conditions affect breeding time, and its consequences for reproduction, in a white-throated dipper Cinclus cinclus population in a river system in Norway during 34 years (1978–2011). Hatching date advanced almost nine days, indicating a response to higher temperatures and the advanced phenology in the area. Earlier breeding was found in warm springs and at lower altitudes. High population density facilitated earlier breeding close to the coast. Furthermore, when population density was low, breeding was early at territories that were rarely occupied, while in years with high density, breeding was early at territories that were frequently occupied. Also, when population density was low, earlier breeding occurred at territories that on average produced more offspring than other territories, while there was no difference in breeding time in high population years. Selection for early breeding was dependent on spring temperatures and high spring temperatures contributed to higher breeding success during the study period. We found that breeding phenology may have strong effects on fitness in the white-throated dipper, and thus that breeding time is an important ecological factor in a species that feeds mainly on aquatic rather than terrestrial prey.

• Bustnes, Jan Ove; Moe, Børge; Helberg, Morten & Phillips, Richard A. (2013). Rapid long-distance migration in Norwegian Lesser Black-backed Gulls Larus fuscus fuscus along their eastern flyway. IBIS. ISSN 0019-1019. 155(2), s. 402–406. doi: 10.1111/ibi.12022. Fulltekst i vitenarkiv
• Helberg, Morten; Systad, Geir Helge; Birkeland, Ingve; Lorentzen, Nils H. & Bustnes, Jan Ove (2009). Migration patterns of adult and juvenile Lesser Black-backed Gulls Larus fuscus from northern Norway. Ardea. ISSN 0373-2266. 97(3), s. 281–286. Fulltekst i vitenarkiv
• Bustnes, Jan Ove; Fauchald, Per; Tveraa, Torkild; Helberg, Morten & Skåre, Janneche Utne (2008). The potential impact of environmental variation on the concentrations and ecological effects of pollutants in a marine avian top predator. Environment International. ISSN 0160-4120. 34, s. 193–201. Fulltekst i vitenarkiv Vis sammendrag

  Concentrations of organochlorine contaminants (OCs) and associations between OCs and fitness components were examined in great blackbacked gulls (Larus marinus) in three colonies along the coast of northern Norway. In one of the colonies, data were collected in two subsequent seasons. Concentrations of four OCs (HCB, oxychlordane, DDE and PCB) were measured in blood (n=260) and fitness components (reproductive variables and adult return rate between breeding seasons) were recorded. In the first year, in two of the colonies, body condition and reproductive performance among the gulls were poor compared to the third colony, suggesting spatial variation in environmental conditions, especially food availability. However, in the third colony, body condition and reproductive performance were even better in the second season; i.e. environmental conditions varied temporally. OC residues were higher in the colonies where environmental conditions were poor, but much of this variation was explained by differences in body condition among colonies. Moreover, concurrent with improved body condition from one season to the next, the concentrations of OCs were halved. In the two colonies where environmental conditions were poor, female OC residues were negatively related to egg-laying date, egg size and nesting success, and in the colony where the concentrations of OC were highest, gulls with elevated DDE residues had low probability of returning between breeding seasons. In comparison, in the colony where environmental conditions were better in the first year, other types of adverse relationships between OCs and fitness components were found; i.e. chicks from females with high OC concentrations were in poor condition at hatching, suggesting maternal transfer of OCs to the eggs, and males with high OC residues had poor nesting success and chick survival, suggesting OC-mediated behavioural changes. With improved environmental conditions and lower OC concentrations in the second season, no significant adverse relationships between OCs and fitness components were found. This study thus suggests that there are complex interrelationships between both concentrations and ecological effects of OCs, and the environment, indicating that effects of OCs in nature may only be assessed after considering environmental variation.

• Bustnes, JO; Kristiansen, Kai-Ove & Helberg, Morten (2007). Immune status, carotenoid coloration, and wing feather growth in relation to organochlorine pollutants in great black-backed gulls. Archives of Environmental Contamination and Toxicology. ISSN 0090-4341. 53. doi: 10.1007/s00244-005-0269-3. Fulltekst i vitenarkiv
• Kristiansen, Kai-Ove; Bustnes, JO; Folstad, Ivar & Helberg, Morten (2006). Carotenoid coloration in great black-backed gull Larus marinus reflects individual quality. Journal of Avian Biology. ISSN 0908-8857. 37. Fulltekst i vitenarkiv
• Bustnes, Jan Ove; Helberg, Morten; Strann, Karl-Birger & Skåre, Janneche Utne (2006). Environmental pollutants in endangered vs. increasing subspecies of the lesser black-backed gull on the Norwegian Coast. Environmental Pollution (1987). ISSN 0269-7491. 144, s. 893–901. Fulltekst i vitenarkiv
• Helberg, Morten; Bustnes, Jan Ove; Erikstad, K. E.; Kristiansen, Kai Ove & Skåre, Janneche Utne (2005). Relationships between reproductive performance and organochlorine contaminants in great black-backed gulls (Larus marinus). Environmental Pollution (1987). ISSN 0269-7491. 134(3), s. 475–483. Fulltekst i vitenarkiv

Se alle arbeider i NVA

• Braaten, Espen; Eikeseth, Unni; Helberg, Morten; Lesund, Brit Drøivoldsmo & Voll, Liv Oddrun (2021). Solaris naturfag 6. Aschehoug & Co. ISBN 9788203406607. 272 s. Fulltekst i vitenarkiv
• Svorkmo-Lundberg, Torkild; Bakken, Vidar; Helberg, Morten; Mork, Kjetil; Røer, Jan Erik & Sæbø, Solve (2006). Norsk VinterfuglAtlas : Fuglenes utbredelse, bestandsstørrelse og økologi vinterstid. Norsk Ornitologisk Forening. ISBN 9788278520734. 496 s. Fulltekst i vitenarkiv
• Svorkmo-Lundberg, Torkild; Bakken, Vidar; Helberg, Morten; Mork, Kjetil; Røer, Jan Erik & Sæbø, Solve (2006). Norsk VinterfuglAtlas : Fuglenes utbredelse, bestandsstørrelse og økologi vinterstid. Norsk Ornitologisk Forening. ISBN 9788278520734. 496 s. Fulltekst i vitenarkiv

Se alle arbeider i NVA

• Rømo, Grim; Åkesson, Caroline Piercey; Reiertsen, Tone Kristin; Fosse, Johanna Hol; Arnason_Bøe, Cathrine & Austbø, Lars [Vis alle 16 forfattere av denne artikkelen] (2025). Mass Mortality Caused by Highly Pathogenic Avian Influenza H5N1 in Black-legged Kittiwakes in Norway during Breeding Season 2023. Fulltekst i vitenarkiv
• Critchley, Emma Jane; Nilsson, Anna Lisa Kristina; Helberg, Morten & May, Roelof Frans (2024). Life-cycle impact assessment of offshore wind energy development on migrating seabird diversity in the North Sea. Fulltekst i vitenarkiv
• Tarroux, Arnaud; Amelineau, Francoise; Anker-Nilssen, Tycho; Bjørnstad, Oskar; Bringsvor, Ingar Støyle & Bråthen, Vegard Sandøy [Vis alle 44 forfattere av denne artikkelen] (2021). Year-round exposure of pelagic Arctic-breeding seabirds to fisheries and other anthropogenic stressors in the Northeast Atlantic. Fulltekst i vitenarkiv
• Gudmundsson, Sveinn H; Madslien, Knut Ivar Engesæter; Rømo, Grim; Gjerset, Britt; Moldal, Torfinn & Follestad, Arne [Vis alle 8 forfattere av denne artikkelen] (2021). Høypatogen fugleinfluensa påvist i Norge. Norsk veterinærtidsskrift. ISSN 0332-5741. s. 140–142. Fulltekst i vitenarkiv Vis sammendrag

  Russland og etter hvert flere andre europeiske land (bl.a. Danmark og Storbritannia) hadde i løpet av høsten 2020 meldt om tilfeller av høypatogen fugleinfluensa (HPAI) av typen H5N8 og i november ble denne virusvarianten også påvist i Norge. Det er første gang høypatogen fugleinfluensa (HPAI) blir påvist her til lands. I denne artikkelen blir tiltakene som ble iverksatt beskrevet i tillegg til historien rundt den første påvisningen.

• Knudtzon, Nina Cathrine; Thorstensen, Helene; Ruus, Anders; Helberg, Morten; Bæk, Kine & Enge, Ellen Katrin [Vis alle 7 forfattere av denne artikkelen] (2021). Maternal Transfer and Occurrence of Siloxanes, Chlorinated Paraffins and Legacy POPs in Herring Gulls (Larus argentatus) of Different Urban Influence. Fulltekst i vitenarkiv
• Thorstensen, H. S.; Ruus, Anders; Helberg, Morten; Bæk, Kine; Enge, Ellen Katrin & Borgå, Katrine (2020). Herring gull and common eider as indicators of contaminants in an urban fjord. Fulltekst i vitenarkiv
• Ruus, Anders; Helberg, Morten; Knudtzon, Nina Cathrine; Bæk, Kine; Enge, Ellen Katrin & Borgå, Katrine (2020). Emerging and legacy contaminants in two urban herring gull colonies. Fulltekst i vitenarkiv
• Ruus, Anders; Helberg, Morten; Bæk, Kine; Enge, Ellen Katrin & Borgå, Katrine (2020). Common eider and herring gull as indicators of contaminants in an urban fjord system. Fulltekst i vitenarkiv
• Båtvik, Jan Ingar Iversen & Helberg, Morten (2019). An der Eismeerküste – Norwegens frostiger Norden. [TV]. MareTV. Fulltekst i vitenarkiv Vis sammendrag

  TV-selskapet filmet en del av aktivitetene fra nordområdene også i Vardø og Kiberg havn i Øst-Finnmark. Her fanget Morten Helberg ei krykkje som ble ringmerket og vist fram for en skoleklasse i Vardø. Jan Ingar Båtvik fanget en stellerand i Kiberg for blodprøvetaking og ringmerking og hvor TV-selskapet var og filmet. De fikk en orientering om hva vi holdt på med, litt om stellerand og dens krav til tilværelsen før frislippet av denne.

• Widerøe, Ina Kirsten Sundal; Rasmussen, Adrian Kristinsønn; Aae, Rune; Braaten, Bjørn Espen Pontus; Båtvik, Jan Ingar Iversen & Halstvedt, Camilla Blikstad [Vis alle 9 forfattere av denne artikkelen] (2019). Naturfag i framtidens skole: Inn med teknologi, ut med uteskole? Fulltekst i vitenarkiv
• Baggott, Carl David & Helberg, Morten (2018). Breeding ‘Baltic Gulls’ from the Horsvær archipelago in Norway and the occurrence of such birds in Britain. British Birds. ISSN 0007-0335. 111, s. 499–511. Fulltekst i vitenarkiv
• Keilen, Ellen Kristine; Borgå, Katrine; Ruus, Anders; Helberg, Morten; Reiertsen, Tone & Warner, Nicholas Alexander [Vis alle 7 forfattere av denne artikkelen] (2017). Levels and effects of environmental contaminants in herring gull (Larus argentatus) from an urban and a rural colony in Norway. Fulltekst i vitenarkiv
• Helberg, Morten (2015). Do climate have an impact on survival in wintering Gulls? Fulltekst i vitenarkiv
• Helberg, Morten (2014). Dramatisk nedgang i måkebestanden - nå skal de finne ut hvorfor. Fulltekst i vitenarkiv
• Helberg, Morten (2013). Seabird survival in relation to climate change. Fulltekst i vitenarkiv
• Breistøl, Arild & Helberg, Morten (2012). Dystre tall for hettemåkebestanden i Norge. Vår Fuglefauna. ISSN 0332-5601. 35(4), s. 150–157. Fulltekst i vitenarkiv
• Helberg, Morten (2012). Is optimal seabird monitoring scale at colonial, regional or global level? An evaluation of the use of mark-sight-resight methods. Fulltekst i vitenarkiv
• Helberg, Morten (2011). Bymåkene skal under lupen. [Journal]. Stavanger Aftenblad. Fulltekst i vitenarkiv
• Helberg, Morten (2011). Vil forske på urbane måser. s. 6–6. Fulltekst i vitenarkiv
• Helberg, Morten; Breistøl, Arild & Lorentzen, Nils Helge (2011). Hvordan går det med hettemåkene i Norge? Vår Fuglefauna. ISSN 0332-5601. 34(1), s. 6–11. Fulltekst i vitenarkiv
• Ruus, Anders; Grung, Merete; Bæk, Kine; Rundberget, Thomas; Beylich, Bjørnar & Hanssen, Linda [Vis alle 8 forfattere av denne artikkelen] (2026). Environmental Contaminants in an Urban Fjord, 2025. Norsk institutt for vannforskning (NIVA). ISSN 9788257779498. Fulltekst i vitenarkiv Vis sammendrag

  This report presents data from the last year of a 5-year period of the Urban Fjord programme. The programme started in 2013 and has since been altered/advanced. In 2025 the programme covers sampling and analyses of sediment, polychaetes, krill, shrimps, blue mussels, herring, cod, eider, and herring gull from the Inner Oslofjord. A total of 230 single compounds/isomers were analysed, and frequent detection was found of specific PFAS compounds (e.g. PFOS) in most matrices, certain QACs in several matrices (ATAC-C22 in all matrices), specific benzothiazoles in eider blood, LCCPs in certain matrices, certain siloxanes in most matrices, metals in all matrices and PCBs in all matrices. Biomagnification was observed for 24 PCB congeners, LCCPs and D4 (siloxane; lipid wt. basis). Furthermore, biomagnification was observed for PFOSA, ATAC-C20 and ATAC-C22, as well as for the metals As and Hg (wet wt. basis).

• Granstad, Silje; Ytrehus, Bjørnar; Helberg, Morten; Gjerset, Britt; Arnason_Bøe, Cathrine & Ånestad, Lise Marie [Vis alle 13 forfattere av denne artikkelen] (2025). Statusrapport: Høypatogen aviær influensa - Veterinærinstituttet, oktober 2025. Veterinærinstituttet. Fulltekst i vitenarkiv Vis sammendrag

  Høypatogen aviær influensa (HPAI) H5N1 fortsatte å dominere i Europa fra april til oktober 2025. Blant villfugl var det flest påvisninger blant ender, gjess og måker, mens det blant fjørfe var flest utbrudd hos ender og høns i Ungarn og Polen.

• Granstad, Silje; Ytrehus, Bjørnar; Helberg, Morten; Åkerstedt, Johan; Gjerset, Britt & Arnason_Bøe, Cathrine [Vis alle 14 forfattere av denne artikkelen] (2025). Statusrapport: Høypatogen aviær influensa - Veterinærinstituttet, april 2025. Veterinærinstituttet. Fulltekst i vitenarkiv Vis sammendrag

  Antallet påvisninger hos fugl av fugleinfluensa i Europa fra oktober 2024 til april 2025, viste en liten oppgang sammenlignet med samme periode året før.

• Nilsson, Anna Lisa Kristina; Breistøl, Arild; Helberg, Morten & Molværsmyr, Sindre (2025). Fungerer vern og ferdselsrestriksjoner for sjøfuglene? Bestandsutvikling, hekkesuksess og rekruttering hos gråmåke i og utenfor sjøfuglreservatene. Norsk institutt for naturforskning (NINA). ISSN 9788242655141. Fulltekst i vitenarkiv Vis sammendrag

  Nilsson, A.L.K., Breistøl, A., Helberg, M. & Molværsmyr, S. 2025. Fungerer vern og ferdselsrestriksjoner for sjøfuglene? Bestandsutvikling, hekkesuksess og rekruttering hos gråmåke i og utenfor sjøfuglreservatene. NINA Rapport 2687. Norsk institutt for naturforskning. Nedgangene i sjøfuglbestandene er nå så omfattende at en tilsynelatende vanlig art som gråmåke Larus argentatus er blitt tatt med på den norske rødlisten over truede arter. Av alle årsaker som bidrar til bestandsnedgangene hos norske og internasjonale sjøfuglbestander er menneskelig forstyrrelse i hekketiden en årsak som ofte adresseres av forvaltningen med ferdselsrestriksjoner på hekkeplassene. Siden det er få, om noen, studier som kan påvise positiv effekt av dette tiltaket, er det stor usikkerhet om disse forvaltningstiltakene har den ønskede effekten. I dette arbeidet undersøkte vi effekten av ferdselsrestriksjonene gjennom å studere forskjell i utviklingen i kolonistørrelse og ungeproduksjon mellom vernede og ikke-vernede sjøfuglkolonier. I tillegg studerte vi rekrutteringen til og fra disse koloniene i et skjærgårdsområde på Sørlandet med mange vernede og ikke-vernede kolonier. Vi brukte tidsserier på kolonistørrelse og ungeproduksjon fra BirdLife Mandal og SEAPOP, og data fra fargeringmerkingsbasen ringmerking.no for rekrutteringsanalysene. Kolonier med ferdselsrestriksjoner var større og produserte flere unger per par enn kolonier uten. De lokale gråmåkebestandene minket kraftig, med nesten 30 par per tiår, og kolonier uten ferdselsrestriksjoner minket raskere enn vernede kolonier. Ungeproduksjonen sank betraktelig over tid i studieperioden, men ingen statistiske forskjeller i nedgang over tid mellom vernede og ikke-vernede kolonier ble registrert. Unger som var store nok til å få fargering, rekrutterte i likt omfang fra verne- og ikke-verneområde. Imidlertid rekrutterte ungene helst inn i kolonier med samme vernestatus som der de selv ble klekket. Siden gråmåken dermed viser en form for stedtrohet, er forholdene på hekkeplassene svært viktige. Som forvaltningstiltak kan ferdselsrestriksjoner på øyer med hekkende sjøfugl til en viss grad bidra til at fuglene kan hekke uforstyrret, noe som potensielt kan minske hastigheten på bestandsnedgangene. Dette tiltaket er imidlertid ikke nok til å forbedre bestandstrendene for norske gråmåker.

• Reiertsen, Tone Kristin; Breistøl, Arild; Hagestad, Sine; Helberg, Morten; Jacobsen, Karl-Otto & Molværsmyr, Sindre [Vis alle 7 forfattere av denne artikkelen] (2025). Sameksistens med urbane måker og terner – kunnskapsbaserte råd om tiltak og tilrettelegging. Norsk institutt for naturforskning (NINA). ISSN 9788242653956. Fulltekst i vitenarkiv
• Ruus, Anders; Grung, Merete; Jartun, Morten; Bæk, Kine; Rundberget, Thomas & Beylich, Bjørnar [Vis alle 10 forfattere av denne artikkelen] (2023). Environmental Contaminants in an Urban Fjord, 2022. Norsk institutt for vannforskning (NIVA). ISSN 9788257776091. Fulltekst i vitenarkiv Vis sammendrag

  This report presents data from the second year of a new 5-year period of the Urban Fjord programme. The programme started in 2013 and has since been altered/advanced. In 2022 the programme covers sampling and analyses of sediment, polychaetes, krill, shrimps, blue mussels, herring, cod, eider, and herring gull from the Inner Oslofjord. In addition, samples of Harbour seals from the Outer Oslofjord are analysed. A total of ~300 single compounds/isomers were analysed, and frequent detection was found of certain PFAS compounds (such as PFOS) in most matrices, certain QACs in sediment, MCCPs in most matrices (also SCCPs in birds and seals, as well as LCCPs in seals), D5 (siloxane) in all matrices, certain PBDEs (such as BDE 100) in most matrices, PCBs in all matrices, BCPS (phenolic) in seals and certain metals in all matrices. Biomagnification was observed for 28 PCB congeners and 6 PBDEs (lipid wt. basis). Furthermore, biomagnification was observed for 5 PFAS compounds, as well as for the metals As, Ag and Hg (wet wt. basis).

• Layton-Matthews, Kate; Buckingham, Lila; Critchley, Emma Jane; Nilsson, Anna Lisa Kristina; Ollus, Victoria Marja Sofia & Ballesteros, Manuel [Vis alle 16 forfattere av denne artikkelen] (2023). Development of a Cumulative Impact Assessment tool for birds in Norwegian Offshore Waters: Trollvind OWF as a case study. Norsk institutt for naturforskning (NINA). ISSN 9788242650931. Fulltekst i vitenarkiv Vis sammendrag

  - North Sea - Seabirds - Migratory birds - Impact assessment - Offshore wind - Climate change

• Helberg, Morten; Heggøy, Oddvar; Dahl, Espen; Fredriksson, Øyvind; Gunleifsen, Leif & Gunnersen, Jan Edvinn [Vis alle 14 forfattere av denne artikkelen] (2021). Intensiv overvåking av hubro i Norge i 2021. BirdLife Norge. ISSN 9788278521809. Fulltekst i vitenarkiv Vis sammendrag

  Intensiv overvåking av hubro Bubo bubo inngår som en del av oppfølgingen av den nasjonale handlingsplanen for arten, og ble startet opp av Norsk Ornitologisk Forening (NOF) i 2012. Overvåkingen har som mål å undersøke status for hubrotilhold, hekking og ungeproduksjon i et utvalg overvåkingsterritorier. For hvert overvåkingsområde er det lagt ut 15 territorier, hvor hubroenes aktivitet kartlegges med metoder som minimaliserer forstyrrelse for å påvirke fuglene minst mulig. Fire delområder inngikk i intensivovervåkingen t.o.m. 2019 (Telemark, Aust-Agder, Høg-Jæren og Øygarden). I tillegg har hubrobestanden i et område i Nordland (Helgelandskysten) blitt overvåket vha. en noe annerledes metodikk i perioden. Samtidig som overvåkingsmetodikken ble revidert og Statens naturoppsyn (SNO) overtok ansvaret for prosjektet, ble overvåkingen utvidet med et delområde nord i Østerdalen f.o.m. feltsesongen 2020. I 2021 fikk vi tilstrekkelige overvåkingsdata fra 74 av 75 territorier i Sør-Norge, og (for de fleste parametere) fra alle 51 territoriene på Helgeland. Vellykket hekking ble påvist i 13 av 74 territorier i Sør-Norge (18%), og her ble det produsert 23 hubrounger som hadde alder på minst 60 dager (flygedyktig alder). Om hubroungene vokser opp til flygedyktig alder eller ikke, påvises nå ved hjelp av lyttebokser, og denne metoden brukes også tidlig i sesongen, for å kartlegge roping som forteller oss om fuglene er til stede i territoriet. På Helgeland ble alle 51 overvåkingsterritoriene kontrollert, og vellykket hekking ble dokumentert i 15 av disse (29 %). På Helgeland ble det produsert minst 20 hubrounger ved flygedyktig alder, en nedgang fra hekkesesongen 2020, hvor minst 26 hubrounger ble påvist flygedyktige. Også for territoriene i Sør-Norge er det en nedgang fra 2020 til 2021, fra 34 hubrounger i 2020 til 23 i 2021.

• Molværsmyr, Sindre; Follestad, Arne & Helberg, Morten (2020). Fuglebevegelser til Norge med risiko for innføring av fugleinfluensa. Med fokus på måker og gjess. Norsk institutt for naturforskning (NINA). ISSN 9788242647122. Fulltekst i vitenarkiv Vis sammendrag

  Fugleinfluensa, fugletrekk, smittespredning, svartbak, gråmåke, kortnebbgås, grågås, hvitkinngås, tundragås, ringmerking, fargemerking, halsring, - Avian flu, bird migration, spread of infection, great black-backed gull, herring gull, pink-footed goose, greylag goose, barnacle goose, greater white-fronted goose, bird ringing, color ringing, neck bands

• Ruus, Anders; Bæk, Kine; Rundberget, Thomas; Allan, Ian; Beylich, Bjørnar & Vogelsang, Christian [Vis alle 10 forfattere av denne artikkelen] (2020). Environmental Contaminants in an Urban Fjord, 2019. Norsk institutt for vannforskning (NIVA). ISSN 9788257772901. Fulltekst i vitenarkiv Vis sammendrag

  This programme, “Environmental Contaminants in an Urban Fjord” has covered sampling and analyses of sediment and organisms in a marine food web of the Inner Oslofjord, in addition to samples of blood and eggs from herring gull. The programme also included inputs of pollutants via surface water (storm water), and effluent water and sludge from a sewage treatment plant. The bioaccumulation potential of the contaminants in the Oslo fjord food web was evaluated. The exposure to/accumulation of the contaminants was also assessed in birds. A vast number of chemical parameters have been quantified, in addition to some biological effect parameters in cod, and the report serves as a status description of the concentrations of these chemicals in different compartments of the Inner Oslofjord marine ecosystem.

• Ruus, Anders; Bæk, Kine; Rundberget, Thomas; Allan, Ian; Beylich, Bjørnar & Schlabach, Martin [Vis alle 10 forfattere av denne artikkelen] (2019). Environmental Contaminants in an Urban Fjord, 2018. Norsk institutt for vannforskning (NIVA). ISSN 9788257771454. Fulltekst i vitenarkiv Vis sammendrag

  This programme, “Environmental Contaminants in an Urban Fjord” has covered sampling and analyses of sediment and organisms in a marine food web of the Inner Oslofjord, in addition to samples of blood and eggs from herring gull and eider duck. The programme also included inputs of pollutants via surface water (storm water), and effluent water and sludge from a sewage treatment plant. The bioaccumulation potential of the contaminants in the Oslo fjord food web was evaluated. The exposure to/accumulation of the contaminants was also assessed in birds. A vast number of chemical parameters have been quantified, in addition to some biological effect parameters in cod, and the report serves as valuable documentation of the concentrations of these chemicals in different compartments of the Inner Oslofjord marine ecosystem.

• Molværsmyr, Sindre; Ergon, Torbjørn; Nilsson, Anna & Helberg, Morten (2019). Colony formation and breeding success in the rapidly declining Black-headed Gull. Universitetet i Oslo. Fulltekst i vitenarkiv Vis sammendrag

  Black-headed Gulls are in rapid decline in Norway and is categorized as VU (Vulnerable) on the national Red List. The Norwegian population has decreased from 30 000 pairs around 1990 to just 7000 pairs in 2011. In the study area, the inner Oslo Fjord, the total breeding population counted about 3000 pairs in 2018. This study aims to explain variations in nest and chick survival both within and between colonies, with respect to date of individual nest settlement or colonies establishment, as well as stress elements and colony defence. Multiple colonies were monitored with a combination of nest cameras and drone footage throughout the breeding cycle. From this, data regarding formation, as well as nest and chick survival, were analysed. Of 3050 Black-headed Gull nests monitored in this thesis, one in five produced chicks. Pairs settling early in the breeding season had a much higher nest survival probability than those that settled later. This was true both within and between colonies. Larger colonies had higher nest survival than smaller colonies. The most observable reason for nest and colony failures were predation from Crows, large Gulls, Red Foxes and Badgers. Colonies that failed completely were likely to have a weaker colony defence due to behavioural changes, which made the colony more accessible for predators. Low food availability and a combination of other stress factors are presumed to have made many pairs in the colonies invest less energy in current reproduction and rather focus on own survival and future breeding attempts. From a population perspective, this strategy is sustainable for a few years, but if breeding seasons with low reproduction success are too frequent, the species decline will continue, possible until extinction in Norway.

• Ruus, Anders; Bæk, Kine; Petersen, Karina; Allan, Ian; Beylich, Bjørnar & Schlabach, Martin [Vis alle 9 forfattere av denne artikkelen] (2018). Environmental Contaminants in an Urban Fjord, 2017. Norsk institutt for vannforskning (NIVA). ISSN 9788257771034. Fulltekst i vitenarkiv Vis sammendrag

  This programme, “Environmental Contaminants in an Urban Fjord” has covered sampling and analyses of sediment and organisms in a marine food web of the Inner Oslofjord, in addition to samples of blood and eggs from herring gull and eider duck. The programme also included inputs of pollutants via surface water (storm water), and effluent water and sludge from a sewage treatment plant. The bioaccumulation potential of the contaminants in the Oslo fjord food web was evaluated. The exposure to/accumulation of the contaminants was also assessed in birds. A vast number of chemical parameters have been quantified, in addition to some biological effect parameters in cod, and the report serves as valuable documentation of the concentrations of these chemicals in different compartments of the Inner Oslofjord marine ecosystem.

• Ruus, Anders; Bæk, Kine; Petersen, Karina; Allan, Ian; Beylich, Bjørnar & Schlabach, Martin [Vis alle 8 forfattere av denne artikkelen] (2016). Environmental Contaminants in an Urban Fjord, 2015. Norsk institutt for vannforskning (NIVA). ISSN 9788257768089. Fulltekst i vitenarkiv Vis sammendrag

  This programme, “Environmental Contaminants in an Urban Fjord” has covered sampling and analysis of sediment and organisms in a marine food web of the Inner Oslofjord, in addition to samples of blood and eggs from herring gull. The programme also included inputs of pollutants via surface water (storm water). The bioaccumulation potential of the contaminants in the Oslo fjord food web was evaluated. The exposure to/accumulation of the contaminants was also assessed in herring gull, as an indicator of an urban fjord inhabitant. A vast number of chemical parameters have been quantified, in addition to some biological effect parameters in cod, and the report serves as valuable documentation of the concentrations of these chemicals in different compartments of the Inner Oslofjord marine ecosystem. Furthermore, this report presents relationships between the contaminant concentrations and various biological variables.

• Ruus, Anders; Allan, Ian; Beylich, Bjørnar; Bæk, Kine; Schlabach, Martin & Helberg, Morten (2015). Environmental Contaminants in an Urban Fjord, 2014. Norsk institutt for vannforskning (NIVA). ISSN 9788257766191. Fulltekst i vitenarkiv Vis sammendrag

  This programme, “Environmental Contaminants in an Urban Fjord” has covered sampling and analysis of organisms in a marine food web of the Inner Oslofjord, in addition to samples of sediment, blue mussel and polychaetes at selected locations in the fjord. The programme also included inputs of pollutants via surface water (storm water). Results from other monitoring programmes such as "Contaminants in coastal areas" (MILKYS) and "Riverine inputs and direct discharges to Norwegian coastal waters" (RID), as well as results from other input measurements to the inner Oslofjord, and measurements of contaminants at Bekkelaget sewage treatment plant are referred and placed in context with the results of the present programme. A vast number of chemical parameters have been quantified, and the report serves as valuable documentation of the concentrations of these chemicals in different compartments of the Inner Oslofjord marine ecosystem. Furthermore, this report presents relationships between the contaminant concentrations and various biological variables.

• Ruus, Anders; Allan, Ian; Beylich, Bjørnar; Bæk, Kine; Schlabach, Martin & Helberg, Morten (2014). Environmental Contaminants in an Urban Fjord. Norsk institutt for vannforskning (NIVA). ISSN 9788257764494. Fulltekst i vitenarkiv Vis sammendrag

  This programme, “Environmental Contaminants in an Urban Fjord” has covered sampling and analysis of organisms in a marine food web of the Inner Oslofjord, in addition to samples of sediment, blue mussel and polychaetes at selected locations in the fjord. The programme also included inputs of pollutants via surface water (storm water). Results from other monitoring programmes such as "Contaminants in coastal areas" (MILKYS) and "Riverine inputs and direct discharges to Norwegian coastal waters" (RID), as well as results from other input measurements to the inner Oslofjord, and measurements of contaminants at Bekkelaget sewage treatment plant are referred and placed in context with the results of the present programme. A vast number of chemical parameters have been quantified, and the report serves as valuable documentation of the concentrations of these chemicals in different compartments of the Inner Oslofjord marine ecosystem. Furthermore, this report presents relationships between the contaminant concentrations and various biological variables.

• Helberg, Morten; Johnsen, Trond Vidar & Fauchald, Per (2005). Registrering av sjøfugl fra flytokt. Barentshavet øst, 8.februar 2005. Norsk institutt for naturforskning (NINA). ISSN 9788242615640. Fulltekst i vitenarkiv Vis sammendrag

  I forbindelse med prøveboring i Barentshavet utførte NINA på oppdrag for Norsk Hydro et flytokt for å gi en oversikt over fordelingen av sjøfugl i området rundt oljeriggen Eirik Raude. Flytoktet ble utført innenfor et stort område i Barentshavet i løpet av 4,5 timers flytid den 8. februar 2005. Oppdagbarheten av spesielt alkefugl fra fly er lav og svært sårbar for dårlige lys- og værforhold. Registrering fra fly gir derfor svært usikre estimater med hensyn til antall fugl. Flytellinger dekker imidlertid store områder på kort tid, og er derfor egnet til å gi et generelt øyeblikksbilde over fordelingen av fugl innenfor store område. Det ble ikke oppdaget noen store konsentrasjoner av sjøfugl i det undersøkte området. Havhest var den mest tallrike arten.

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