Clare Margaret Andvik

• Jourdain, Eve Marie; McKinney, Melissa A.; Remili, Anaïs; Andvik, Clare Margaret; Fagerlund, Carl Johan Ludwig & Karoliussen, Richard [Show all 8 contributors for this article] (2026). Advancing Amino Acid Isotope‐Inferred Trophic Ecology in an Apex Predator: Insights From a Data‐Rich Killer Whale Population. Ecology and Evolution. 16(8), p. 1–16. doi: 10.1002/ece3.74121. Full text in Research Archive Show summary

  Amino acid‐specific nitrogen isotope analysis (δ 15 N‐AA) is increasingly used to infer trophic ecology, yet remains poorly validated in marine predators. We analyzed bulk tissue δ 15 N ( 15 N/ 14 N) and δ 13 C ( 13 C/ 12 C), and δ 15 N‐AA in 105 skin samples collected from individually identified Norwegian killer whales between 2017 and 2023. Forty‐two individuals with best documented diets in 2010–2023, based on field observations and corroborated by mercury concentrations and bulk tissue δ 15 N values in skin, provided reference diet groups against which δ 15 N‐AA‐derived hypotheses were tested: Fish‐only (100% fish prey; n  = 15), Intermediate mixed diet (~10% mammalian prey in addition to fish; n  = 14), and Top mixed diet (~50% mammals, 50% fish prey; n  = 13). Univariate and multivariate approaches identified diet as the primary driver of δ 15 N variation across individual amino acids and multivariate isotopic space, whereas sex and life stage had little effect. However, substantial inter‐individual variation remained unexplained and appeared to reflect metabolic processes. Metrics δ 15 N ΣTrophic—ΣSource (δ 15 N difference between the sum of trophic amino acids and the sum of source amino acids) and isotopic difference between glutamic acid/glutamine (Glu) and phenylalanine (Phe) (δ 15 N Glu–Phe ) successfully identified Top mixed diet whales but lacked the sensitivity to identify Intermediate mixed diet individuals, whilst δ 15 N values of Threonine showed no relationship with trophic position. Proline (Pro) and Phe used as trophic‐source pair provided the first plausible δ 15 N‐AA‐derived trophic position estimates for killer whales and performed better than bulk isotope‐derived trophic position when a priori knowledge was not available. Multivariate clustering of δ 15 N‐AA data complemented trophic position estimates by resolving finer‐scale dietary variation occurring within trophic levels.

• Andvik, Clare Margaret; Fagerlund, Carl Johan Ludwig; Jourdain, Eve Marie; Yuan, Bo; Haddad-Weiser, Gabrielle & Lyche, Jan Ludvig [Show all 9 contributors for this article] (2026). Comparing polychlorinated n-alkane occurrence and biomagnification with legacy contaminants in a killer whale food web. Environmental Research. ISSN 0013-9351. 306. doi: 10.1016/j.envres.2026.125367. Full text in Research Archive Show summary

  Polychlorinated n-alkanes (PCAs), the largest component of the commercial product chlorinated paraffins, have been used globally in increasing amounts since the regulations of legacy contaminants, such as polychlorinated biphenyls (PCBs). The bioaccumulative potential of PCAs compared to legacy contaminants is inconclusive, with limited data available for PCAs with carbon chain length ≤9 and ≥18, particularly in food webs which include mammalian top predators. Here, we analysed and compared PCAs of different carbon chain length (very-short: PCAs-C6-9 [vSCCPs], short: PCAs-C10-13 [SCCPs], medium: PCAs-C14-17 [MCCPs], and long: PCAs-C18-24 [LCCPs]), 57 legacy contaminants, and total mercury (Hg) in killer whales (Orcinus orca) from northern Norway (n = 59) and a range of fish and marine mammals. We found that legacy organic contaminants dominated in concentration and pattern in marine mammals (54–87%), whereas PCAs and Hg dominated in fishes (58–98%). A species' physiology (poikilotherm or homeotherm) influenced the food web magnification of several contaminants, with estimated trophic magnification factors (TMFs) underestimated in PCAs, and overestimated in PCB-153, p.p’-DDE and Hg, if unaccounted for. PCAs-C6-9 and PCAs-C10-13 had similar and low TMFs for poikilotherms and homeotherms, and similar to PCB-28 (TMF range: 1.9–2.4 [95% confidence interval 0.9–5.7]). PCAs-C14-17 and PCAs-C18-24, had high TMFs in poikilotherms (4.8 [1.3–18] and 4.6 [1.2–18], respectively), and no significant trophic magnification in homeotherms (1.0 [0.5–2.3] and 1.0 [0.4–2.8], respectively), with the opposite pattern for PCB-153 and p.p’-DDE. Our results indicate higher PCA concentrations and biomagnification potential in poikilotherms than homeotherms, which is likely due to lower biotransformation and elimination ability.

• Dulgheriu, Daniela; Andvik, Clare Margaret; Jourdain, Eve Marie; Borgå, Katrine; Ruus, Anders & Haug, Tore [Show all 9 contributors for this article] (2026). A sensitive liquid chromatography–tandem mass spectrometry analytical method of steroid hormones in small blubber samples from four whale species. Conservation Physiology. 14(1). doi: 10.1093/conphys/coag023. Full text in Research Archive Show summary

  Steroid hormones can give an indication of stress, physiological health and reproductive status in whales; however, analysis is often limited by sample mass. We developed a sensitive analytical method using solid phase extraction–liquid chromatography–electrospray ionization–tandem mass spectrometry (LC–ESI–MS/MS) for the identification and quantification of eight steroid hormones (cortisol, cortisone, testosterone, androstenedione, progesterone, 11-deoxycortisol, 11-deoxycorticosterone and 17-hydroxyprogesterone) in small amounts of whale blubber (≤50 mg). Blubber biopsies were collected from stranded killer whales (Orcinus orca; n = 7), harbour porpoises (Phocoena phocoena; n = 3) and sperm whales (Physeter macrocephalus; n = 4), harvested common minke whales (n = 10; Balaenoptera acutorostrata) and free-living killer whales (n = 2) in Norway and the Barents Sea. Steroid hormones were separated using pentafluorophenyl propyl stationary phase and an optimized gradient programme with a total 20-min run. All samples (n = 26) were analysed at 50-mg sample mass, and a subset (n = 11) at 25 mg or lower. Low limit of detection and limit of quantification values resulted in high detection rates of hormones, and we found similar hormone concentrations between parallel samples and at the lowest tested sample mass (14 mg). Cortisol concentrations in sperm whales (4.3 ± 1.6 ng/g) were four times higher than stranded killer whales (1.1 ± 0.96 ng/g), which in turn were up to four times higher than free-living killer whales (0.23 ± 0.12 ng/g), harbour porpoise (0.64 ± 0.38 ng/g) and harvested minke whales (0.22 ± 0.13), possibly due to fatality type and duration of stress prior to death. We provide the first quantification of blubber steroid hormones in killer whale, minke whale, sperm whale and harbour porpoise, and in less than 50-mg sample mass. By minimizing sample mass without compromising precision or sensitivity, our method allows for steroid hormone analysis even on samples with limited availability, strengthening our ability to monitor and conserve marine mammal populations.

• Andvik, Clare Margaret; Jourdain, Eve Marie; Borgen, Anders; Lyche, Jan Ludvig; Karoliussen, Richard & Haug, Tore [Show all 7 contributors for this article] (2024). Intercorrelations of Chlorinated Paraffins, Dechloranes, and Legacy Persistent Organic Pollutants in 10 Species of Marine Mammals from Norway, in Light of Dietary Niche. Environmental Science and Technology. ISSN 0013-936X. 58(33), p. 14797–14811. doi: 10.1021/acs.est.4c02625. Full text in Research Archive Show summary

  Short-, medium-, and long-chain chlorinated paraffins (CPs) (SCCPs, MCCPs, and LCCPs) and dechloranes are chemicals of emerging concern; however, little is known of their bioaccumulative potential compared to legacy contaminants in marine mammals. Here, we analyzed SCCPs, MCCPs, LCCPs, 7 dechloranes, 4 emerging brominated flame retardants, and 64 legacy contaminants, including polychlorinated biphenyls (PCBs), in the blubber of 46 individual marine mammals, representing 10 species, from Norway. Dietary niche was modeled based on stable isotopes of nitrogen and carbon in the skin/muscle to assess the contaminant accumulation in relation to diet. SCCPs and dechlorane-602 were strongly positively correlated with legacy contaminants and highest in killer (Orcinus orca) and sperm (Physeter macrocephalus) whales (median SCCPs: 160 ng/g lw; 230 ng/g lw and median dechlorane-602: 3.8 ng/g lw; 2.0 ng/g lw, respectively). In contrast, MCCPs and LCCPs were only weakly correlated to recalcitrant legacy contaminants and were highest in common minke whales (Balaenoptera acutorostrata; median MCCPs: 480 ng/g lw and LCCPs: 240 ng/g lw). The total contaminant load in all species was dominated by PCBs and legacy chlorinated pesticides (63–98%), and MCCPs dominated the total CP load (42–68%, except 11% in the long-finned pilot whale Globicephala melas). Surprisingly, we found no relation between contaminant concentrations and dietary niche, suggesting that other large species differences may be masking effects of diet such as lifespan or biotransformation and elimination capacities. CP and dechlorane concentrations were higher than in other marine mammals from the (sub)Arctic, and they were present in a killer whale neonate, indicating bioaccumulative properties and a potential for maternal transfer in these predominantly unregulated chemicals.

• Andvik, Clare; Bories, Pierre; Harju, Mikael; Borgå, Katrine; Jourdain, Eve & Karoliussen, Richard [Show all 9 contributors for this article] (2023). Phthalate contamination in marine mammals off the Norwegian coast. Marine Pollution Bulletin. ISSN 0025-326X. 199. doi: 10.1016/j.marpolbul.2023.115936. Full text in Research Archive Show summary

  Phthalates are used in plastics, found throughout the marine environment and have the potential to cause adverse health effects. In the present study, we quantified blubber concentrations of 11 phthalates in 16 samples from stranded and/or free-living marine mammals from the Norwegian coast: the killer whale (Orcinus orca), sperm whale (Physeter macrocephalus), long-finned pilot whale (Globicephala melas), white-beaked dolphin (Lagenorhynchus albirostris), harbour porpoise (Phocoena phocoena), and harbour seal (Phoca vitulina). Five compounds were detected across all samples: benzyl butyl phthalate (BBP; in 50 % of samples), bis(2-ethylhexyl) phthalate (DEHP; 33 %), diisononyl phthalate (DiNP; 33 %), diisobutyl phthalate (DiBP; 19 %), and dioctyl phthalate (DOP; 13 %). Overall, the most contaminated individual was the white-beaked dolphin, whilst the lowest concentrations were measured in the killer whale, sperm whale and long-finned pilot whale. We found no phthalates in the neonate killer whale. The present study is important for future monitoring and management of these toxic compounds.

• Gormley, Kate; Hague, Emily; Andvik, Clare Margaret; DaCosta, Valentina; Davies, Abigail & Diz, Daniela [Show all 8 contributors for this article] (2023). First port of call: a horizon scanning workshop for sustainable Arctic marine infrastructure. The Polar Journal. ISSN 2154-896X. 13(1), p. 146–162. doi: 10.1080/2154896X.2023.2205243. Full text in Research Archive Show summary

  To support the predicted growth of shipping activities in the Arctic region in coming decades, port developments and associated shipping infrastructure will be required to be developed in both Arctic and sub-Arctic areas. Such large-scale development in unique and potentially vulnerable areas are likely to have wide-ranging effects and associated impacts. We therefore consider the future challenges, opportunities and knowledge gaps associated with the environmental impacts of developing Arctic and sub-Arctic port infrastructure. Here we present the outputs of an international, virtual workshop held in January 2022 exploring this theme. The workshop brought together Arctic, marine and port researchers, practitioners, non-governmental organisations, and local communities representing a range of geographies and disciplines. Based on pre-workshop consultation, five topics were considered: marine mammals and noise; discharges and pollution; ecosystem impacts and effects; environmental management and assessment; and infrastructure and geography. Dissemination of the workshop found five overriding themes that were common across each topic discussion: i) utilising best practice and governance; ii) community and Indigenous Peoples engagement and participation; iii) common vs. Arctic-specific challenges; iv) impact assessment including consideration of cumulative impacts and effects; and v) climate change. The workshop highlighted the requirement to continue to build and broaden discussion, for further collaborative work and research streams to be developed, to ensure any future Arctic and sub-Arctic port infrastructure, in support of Arctic shipping, is developed sustainably.

• Andvik, Clare Margaret; Haug, Tore; Lyche, Jan Ludvig & Borgå, Katrine (2023). Emerging and legacy contaminants in common minke whale from the Barents sea. Environmental Pollution. ISSN 1566-0745. 319. doi: 10.1016/j.envpol.2023.121001. Full text in Research Archive Show summary

  Persistent organic pollutants (POPs), including brominated flame retardants (BFRs), perfluoroalkyl substances (PFAS) and metals, can accumulate in marine mammals and be transferred to offspring. In this study, we analyzed 64 lipophilic POPs, including four emerging BFRs, in the blubber, liver and muscle of 17 adult common minke whales (Balaenoptera acutorostrata) from the Barents Sea to investigate occurrence and tissue partitioning. In addition, the placental transfer concentration ratios of 14 PFAS and 17 metals were quantified in the muscle of nine female-fetus pairs to investigate placental transfer. Legacy lipophilic POPs were the dominating compound group in every tissue, and we observed generally lower levels compared to previous studies from 1992 to 2001. We detected the emerging BFRs hexabromobenzene (HBB) and pentabromotoluene (PBT), but in low levels compared to the legacy POPs. We detected nine PFAS, and levels of perfluorooctane sulfonate (PFOS) were higher than detected from the same population in 2011, whilst levels of Hg were comparable to 2011. Levels of lipophilic contaminants were higher in blubber compared to muscle and liver on both a wet weight and lipid adjusted basis, but tissue partitioning of the emerging BFRs could not be determined due to the high number of samples below the limit of detection. The highest muscle ΣPFAS levels were quantified in fetuses (23 ± 8.7 ng/g ww), followed by adult males (7.2 ± 2.0 ng/gg ww) and adult females (4.5 ± 1.1 ng/g ww), showing substantial placental transfer from mother to fetus. In contrast, Hg levels in the fetus were lower than the mother. Levels were under thresholds for risk of health effects in the whales. This study is the first to report occurrence and placental transfer of emerging contaminants in common minke whales from the Barents Sea, contributing valuable new data on pollutant levels in Arctic wildlife.

• MacKenzie, Kirsteen M.; Lydersen, Christian; Haug, Tore; Routti, Heli Anna Irmeli; Aars, Jon & Andvik, Clare Margaret [Show all 13 contributors for this article] (2022). Niches of marine mammals in the European Arctic. Ecological Indicators. ISSN 1470-160X. 136. doi: 10.1016/j.ecolind.2022.108661. Full text in Research Archive Show summary

  The Arctic is warming rapidly, with concomitant sea ice losses and ecosystem changes. The animals most vulnerable to Arctic food web changes are long-lived and slow-growing such as marine mammals, which may not be able to adapt rapidly enough to respond to changes in their resource bases. To determine the current extent and sources of these resource bases, we examined isotopic and trophic niches for marine mammals in the European Arctic using skin carbon (δ13C) and nitrogen (δ 15N) stable isotope (SI) compositions from 10 species: blue, fin, humpback, minke, sperm and white whales, bearded and ringed seals, walruses and polar bears, and dietary fatty acids (FAs) in polar bears, walruses and most of the whale species listed here. SI values showed clear species separation by trophic behaviour and carbon sources. Bearded seals, walruses and white whales had the smallest isotopic niches; these species are all resident High Arctic species and are likely to be particularly vulnerable to changes in Arctic ecosystems. We found clear separation between FA groupings driven by pelagic, benthic and planktonic/algal sources: pelagic FAs in all whales, benthic FAs in walruses, and copepod/algae/dinoflagellate FAs in polar bears, with some polar bear compositions approaching those of the whales and walruses. There is strong niche partitioning between study species with minimal functional redundancy, which could impact Arctic ecosystem structure and connectivity if populations of these large nutrient vectors are reduced or lost.

• Andvik, Clare Margaret; Jourdain, Eve; Lyche, Jan Ludvig; Karoliussen, Richard & Borgå, Katrine (2021). High Levels of Legacy and Emerging Contaminants in Killer Whales (Orcinus orca) from Norway, 2015 to 2017. Environmental Toxicology and Chemistry. ISSN 0730-7268. 40(7), p. 1848–1858. doi: 10.1002/etc.5064. Full text in Research Archive Show summary

  Little is known of the movement or presence of unregulated, emerging contaminants in top predators. The aim of the present study was to conduct the first screening of legacy and emerging contaminants in multiple tissues of killer whales (Orcinus orca) from Norway and investigate tissue partitioning and maternal transfer. Blubber was collected from 8 killer whales in 2015 to 2017, in addition to muscle from 5 of the individuals, and kidney, liver, heart, and spleen from a neonate. We screened for 4 unregulated brominated flame retardants and found pentabromotoluene (PBT) and hexabromobenzene (HBB) at low levels in the blubber of all individuals (median PBT 0.091 ng/g lipid wt, median HBB 1.4 ng/g lipid wt). Levels of PBT and HBB (wet wt) were twice as high in the blubber than the muscle for each individual, confirming preferential accumulation in lipid-rich tissues. Perfluoroalkyl substances and total mercury levels were lower in the neonate than adults, suggesting less efficient maternal transfer of these substances. Polychlorinated biphenyl levels in blubber exceeded the threshold for onset of physiological effects (9 µg/g lipid wt) in 7 of the 8 whales, including the neonate. The presence of PBT and HBB in the neonate is the first evidence of maternal transfer of these unregulated contaminants in marine mammals. Our results are relevant for the continued environmental monitoring of contaminants in the Arctic. Environ Toxicol Chem 2021;40:1850–1860. © 2021 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

• Jourdain, Eve; Andvik, Clare; Karoliussen, Richard; Ruus, Anders; Vongraven, Dag & Borgå, Katrine (2020). Isotopic niche differs between seal and fish-eating killer whales (Orcinus orca) in northern Norway. Ecology and Evolution. 10(9), p. 4115–4127. doi: 10.1002/ece3.6182. Full text in Research Archive Show summary

  Ecological diversity has been reported for killer whales (Orcinus orca) throughout the North Atlantic but patterns of prey specialization have remained poorly understood. We quantify interindividual dietary variations in killer whales (n = 38) sampled throughout the year in 2017–2018 in northern Norway using stable isotopic nitrogen (δ15N: 15N/14N) and carbon (δ13C: 13C/12C) ratios. A Gaussian mixture model assigned sampled individuals to three differentiated clusters, characterized by disparate nonoverlapping isotopic niches, that were consistent with predatory field observations: seal‐eaters, herring‐eaters, and lumpfish‐eaters. Seal‐eaters showed higher δ15N values (mean ± SD: 12.6 ± 0.3‰, range = 12.3–13.2‰, n = 10) compared to herring‐eaters (mean ± SD: 11.7 ± 0.2‰, range = 11.4–11.9‰, n = 19) and lumpfish‐eaters (mean ± SD: 11.6 ± 0.2‰, range = 11.3–11.9, n = 9). Elevated δ15N values for seal‐eaters, regardless of sampling season, confirmed feeding at high trophic levels throughout the year. However, a wide isotopic niche and low measured δ15N values in the seal‐eaters, compared to that of whales that would eat solely seals (δN‐measured = 12.6 vs. δN‐expected = 15.5), indicated a diverse diet that includes both fish and mammal prey. A narrow niche for killer whales sampled at herring and lumpfish seasonal grounds supported seasonal prey specialization reflective of local peaks in prey abundance for the two fish‐eating groups. Our results, thus, show differences in prey specialization within this killer whale population in Norway and that the episodic observations of killer whales feeding on prey other than fish are a consistent behavior, as reflected in different isotopic niches between seal and fish‐eating individuals.

• Andvik, Clare Margaret; Jourdain, Eve; Ruus, Anders; Lyche, Jan Ludvig; Karoliussen, Richard & Borgå, Katrine (2020). Preying on seals pushes killer whales from Norway above pollution effects thresholds. Scientific Reports. 10. doi: 10.1038/s41598-020-68659-y. Full text in Research Archive Show summary

  Killer whales (Orcinus orca) are at risk from high levels of biomagnifying pollutants, such as polychlorinated biphenyls (PCBs) and mercury (Hg). Previous toxicological risk assessments for the Norwegian killer whale population have assumed fish as the primary prey source, and assessed the population as below established effect thresholds. However, some individuals have recently been identified to also feed on seals. This study is the first to quantify levels of pollutants in seal-eating killer whales from northern Norway, and to measure Hg levels in the skin of killer whales worldwide. We found higher levels of all pollutants in seal-eating than fish-eating killer whales, including the emerging brominated flame retardants pentabromoethylbenzene (PBEB), pentabromotoluene (PBT) and hexabromobenzene (HBB). Sum polychlorinated biphenyls (ΣPCBs) in the blubber of seal-eaters (n = 7, geometric mean = 46 µg/g l.w.) were four times higher than fish-eaters (n = 24, geometric mean = 11 µg/g l.w.), which pushed all seal-eating individuals above multiple thresholds for health effects. Total Hg levels in skin of seal-eaters (n = 10, arithmetic mean = 3.7 µg/g d.w.) were twice as high as in fish-eaters (n = 28, arithmetic mean = 1.8 µg/g d.w.). Our results indicate that by feeding on higher trophic prey, the Norwegian killer whale population is at higher risk of health effects from pollution than previously assumed.

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• su, Audrey; Jourdain, Eve Marie; Andvik, Clare Margaret; Rikardsen, Audun H.; Søderstrøm, Sofie & Blévin, Pierre [Show all 7 contributors for this article] (2025). Den forgiftede hvalen Elida. [Internet]. web, social media. doi: https:/akvaplan.no/no/video/2025-09-29/den-forgiftede-hvalen-elida-121104. Full text in Research Archive
• Andvik, Clare Margaret; Jourdain, Eve Marie; Borgen, Anders; Lyche, Jan Ludvig; Karoliussen, Richard & Haug, Tore [Show all 7 contributors for this article] (2025). Intercorrelations of short-, medium- and long-chain chlorinated paraffins, dechloranes and legacy POPs in 10 species of marine mammals from Norway, in light of dietary niche. Full text in Research Archive
• Milne, Stephanie; Andvik, Clare Margaret; Jourdain, Eve Marie; Karoliussen, Richard; Vongraven, Dag & Øien, Nils Inge [Show all 8 contributors for this article] (2024). Temporal trends of dietary patterns and mercury in Norwegian killer whales from contrasting ecosystem states. Full text in Research Archive
• Lee, Kiah Jane Oland; Jourdain, Eve Marie; Remili, Anaïs; Andvik, Clare Margaret; Fagerlund, Carl Johan Ludwig & McKinney, Melissa [Show all 8 contributors for this article] (2024). Profiling the diet of Norwegian killer whales through quantitative fatty acid signature analysis (QFASA) and mercury accumulation. Full text in Research Archive
• Andvik, Clare Margaret; Jourdain, Eve Marie; Dulgheriu, Daniela; Lyche, Jan Ludvig; Karoliussen, Richard & Ruus, Anders [Show all 7 contributors for this article] (2024). Blubber Cortisol Levels in Norwegian Killer Whales: Accounting for Individual Variation is Vital in Assessing Stress Responses to Whale Watching. Full text in Research Archive
• Jourdain, Eve Marie; Borgå, Katrine; Ruus, Anders & Andvik, Clare Margaret (2023). Spekkhoggerflokken trues av gammel gift. Forskerne følger dem tett. [Journal]. Titan.uio.no. Full text in Research Archive
• Fagerlund, Carl Johan Ludwig; Jourdain, Eve Marie; Andvik, Clare Margaret; Yuan, Bo; Ruus, Anders & Borgå, Katrine (2023). Understanding mercury and chlorinated paraffins biomagnification by identifying dietary patterns in killer whales in Norway. Full text in Research Archive
• Andvik, Clare Margaret; Jourdain, Eve Marie; Ruus, Anders & Borgå, Katrine (2023). Effect of multiple stressors on Norwegian killer whales (MULTIWHALE). Full text in Research Archive
• Andvik, Clare Margaret; Jourdain, Eve Marie; Borgen, Anders; Haug, Tore; Karoliussen, Richard & Borgå, Katrine (2023). Short, Medium and Long-chain Chlorinated Paraffins and Dechloranes in Marine Mammals from Norway. Full text in Research Archive
• Andvik, Clare Margaret; Jourdain, Eve Marie; Ruus, Anders & Borgå, Katrine (2023). Effect of multiple stressors on Norwegian killer whales (MULTIWHALE). Full text in Research Archive
• Andvik, Clare Margaret; Jourdain, Eve Marie; Lyche, Jan Ludvig; Enge, Ellen Katrin; Harju, Mikael & Haug, Tore [Show all 8 contributors for this article] (2022). High levels of emerging and legacy contaminants in whales from Norway. Full text in Research Archive
• Andvik, Clare Margaret; Jourdain, Eve Marie; Lyche, Jan Ludvig; Harju, Mikael; Haug, Tore & Enge, Ellen Katrin [Show all 8 contributors for this article] (2021). High levels of emerging and legacy contaminants in stranded marine mammals from Norway. Full text in Research Archive
• Andvik, Clare Margaret; Jourdain, Eve Marie; Ruus, Anders; Lyche, Jan Ludvig; Karoliussen, Richard & Borgå, Katrine (2020). At risk: Preying on seals pushes killer whales from Norway above pollution effects thresholds. Full text in Research Archive
• Jourdain, Eve Marie; Andvik, Clare Margaret; Karoliussen, Richard; Vongraven, Dag; Ruus, Anders & Borgå, Katrine (2019). Variations in ecological niche in Norwegian killer whales (Orcinus orca) inferred from dietary descriptors and observational evidence. Full text in Research Archive
• Andvik, Clare Margaret; Jourdain, Eve Marie; Ruus, Anders; Lyche, Jan Ludvig; Karoliussen, Richard & Borgå, Katrine (2019). Higher levels of organohalogen contaminant and mercury in seal-eating killer whales than fish-eating killer whales in northern Norway. Full text in Research Archive
• Andvik, Clare Margaret (2026). Multiple stressors in Norwegian killer whales: Integrating the effect of chemical pollution with other anthropogenic stressors. Universitetet i Oslo. Full text in Research Archive Show summary

  Stress is a natural part of life. However, whilst organisms have evolved mechanisms over millions of years to cope with natural stressors in their environment, humans have, in the space of a few decades, created a multitude of new stressors that threaten our natural world. This thesis assessed the effect of three stressors – chemical pollution, whale watching tourism, and nutritional stress – on an ecologically, economically and socially important species: the killer whale (Orcinus orca). We used a combination of field and laboratory studies, and developed new analytical techniques for multiple analyses in tiny tissue samples. We first established baseline pollutant and exposure data for Norwegian killer whales. We found that whilst long-regulated “legacy” pollutants dominated the pollutant load, unregulated “emerging” contaminants were an increasing risk, and could also biomagnify and be passed from mother to offspring. We then found potential effects of both pollutants and whale watching on hormone levels, and the expression of stress and immune-related genes. The effect of contaminants on cortisol was further amplified during high whale watching periods, with the strongest stress response in whales with better nutritional status. This thesis presents an interdisciplinary framework for assessing the effect of multiple stressors in a wild population, and emphasises the importance of assessing the effect of stressors in combination.

• MacKenzie, Kirsteen M.; Lydersen, Christian; Haug, Tore; Routti, Heli Anna Irmeli; Aars, Jon & Andvik, Clare Margaret [Show all 13 contributors for this article] (2022). Stable isotope (C&N) and dietary fatty acid compositions (>1%) for marine mammals in the European Arctic. Norwegian Polar Data Centre. Full text in Research Archive
• Andvik, Clare Margaret (2020). Migration of chemical additives from plastic products - A literature review. Miljødirektoratet. Full text in Research Archive

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