Eve Marie Jourdain

• Jourdain, Eve Marie; Karoliussen, Richard; Fordyce Martin, Sarah L.; Langangen, Øystein Ole Gahr; Robeck, Todd & Borgå, Katrine [Show all 8 contributors for this article] (2024). Social and genetic connectivity despite ecological variation in a killer whale network. Proceedings of the Royal Society of London. Biological Sciences. ISSN 0962-8452. 291(2021). doi: 10.1098/rspb.2024.0524.
• 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.

• Remili, Anaïs; Dietz, Rune; Sonne, Christian; Samarra, Filipa I. P.; Rikardsen, Audun H. & Kettemer, Lisa Elena [Show all 16 contributors for this article] (2023). Quantitative fatty acid signature analysis reveals a high level of dietary specialization in killer whales across the North Atlantic. Journal of Animal Ecology. ISSN 0021-8790. 92(6), p. 1216–1229. doi: 10.1111/1365-2656.13920. Full text in Research Archive Show summary

  Quantifying the diet composition of apex marine predators such as killer whales (Orcinus orca) is critical to assessing their food web impacts. Yet, with few exceptions, the feeding ecology of these apex predators remains poorly understood. Here, we use our newly validated quantitative fatty acid signature analysis (QFASA) approach on nearly 200 killer whales and over 900 potential prey to model their diets across the 5000 km span of the North Atlantic. Diet estimates show that killer whales mainly consume other whales in the western North Atlantic (Canadian Arctic, Eastern Canada), seals in the mid-North Atlantic (Greenland), and fish in the eastern North Atlantic (Iceland, Faroe Islands, Norway). Nonetheless, diet estimates also varied widely among individuals within most regions. This level of inter-individual feeding variation should be considered for future ecological studies focusing on killer whales in the North Atlantic and other oceans. These estimates reveal remarkable population- and individual-level variation in the trophic ecology of these killer whales, which can help to assess how their predation impacts community and ecosystem dynamics in changing North Atlantic marine ecosystems. This new approach provides researchers with an invaluable tool to study the feeding ecology of oceanic top predators.

• Jourdain, Eve Marie; Barrett-Lennard, Lance G.; Ellis, Graeme M.; Ford, John K. B.; Karoliussen, Richard & Towers, Jared R. [Show all 7 contributors for this article] (2021). Natural Entrapments of Killer Whales (Orcinus orca): A Review of Cases and Assessment of Intervention Techniques. Frontiers in Conservation Science. 2. doi: 10.3389/fcosc.2021.707616.
• Jourdain, Eve Marie; Goh, Tiffany; Kuningas, Sanna; Similä, Tiu; Vongraven, Dag & Karoliussen, Richard [Show all 8 contributors for this article] (2021). Killer whale (Orcinus orca) population dynamics in response to a period of rapid ecosystem change in the eastern North Atlantic. Ecology and Evolution. ISSN 2045-7758. 11, p. 17289–17306. doi: 10.1002/ece3.8364. Full text in Research Archive Show summary

  This study investigates survival and abundance of killer whales (Orcinus orca) in Norway in 1988–2019 using capture–recapture models of photo-identification data. We merged two datasets collected in a restricted fjord system in 1988–2008 (Period 1) with a third, collected after their preferred herring prey shifted its wintering grounds to more exposed coastal waters in 2012–2019 (Period 2), and investigated any differences between these two periods. The resulting dataset, spanning 32 years, comprised 3284 captures of 1236 whales, including 148 individuals seen in both periods. The best-supported models of survival included the effects of sex and time period, and the presence of transients (whales seen only once). Period 2 had a much larger percentage of transients compared to Period 1 (mean = 30% vs. 5%) and the identification of two groups of whales with different residency patterns revealed heterogeneity in recapture probabilities. This caused estimates of survival rates to be biased downward (females: 0.955 ± 0.027 SE, males: 0.864 ± 0.038 SE) compared to Period 1 (females: 0.998 ± 0.002 SE, males: 0.985 ± 0.009 SE). Accounting for this heterogeneity resulted in estimates of apparent survival close to unity for regularly seen whales in Period 2. A robust design model for Period 2 further supported random temporary emigration at an estimated annual probability of 0.148 (± 0.095 SE). This same model estimated a peak in annual abundance in 2015 at 1061 individuals (95% CI 999–1127), compared to a maximum of 731 (95% CI 505–1059) previously estimated in Period 1, and dropped to 513 (95% CI 488–540) in 2018. Our results indicate variations in the proportion of killer whales present of an undefined population (or populations) in a larger geographical region. Killer whales have adjusted their distribution to shifts in key prey resources, indicating potential to adapt to rapidly changing marine ecosystems.

• Jourdain, Eve Marie; Ugarte, Fernando; Víkingsson, Gísli A.; Samarra, Filipa; Ferguson, Steven H. & Lawson, Jack [Show all 8 contributors for this article] (2019). North Atlantic killer whale Orcinus orca populations: a review of current knowledge and threats to conservation. Mammal Review. ISSN 0305-1838. 49(4), p. 384–400. doi: 10.1111/mam.12168.
• Jourdain, Eve Marie; Vongraven, Dag; Bisther, Anna & Karoliussen, Richard (2017). First longitudinal study of seal-feeding killer whales (Orcinus orca) in Norwegian coastal waters. PLOS ONE. ISSN 1932-6203. 12(6). doi: 10.1371/journal.pone.0180099.
• Jourdain, Eve Marie & Vongraven, Dag (2017). Humpback whale (Megaptera novaeangliae) and killer whale (Orcinus orca) feeding aggregations for foraging on herring (Clupea harengus) in Northern Norway. Mammalian Biology. ISSN 1616-5047. 86, p. 27–32. doi: 10.1016/j.mambio.2017.03.006.

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• 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.

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