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Jon Egil Skjæraasen

Jon Egil Skjæraasen

Telefon: 995 33 850

Arbeider med

  • Population dynamics in Northeast Arctic gadoids
  • Skipped spawning and fecundity regulation
  • Mate choice and mating systems in broadcast spawners
  • Population structure and migration in Northeast Arctic gadoids

 

Curriculum Vitae

EDUCATION
10/2003 PhD (Dr scient) Marine Biology, University of Bergen, Norway
Thesis: ‘Implications of behaviour for maturation and spawning in cod’.
Advisors: Anne Gro Vea Salvanes & Trygve Nilsen
1996-1998 MSc (Cand scient) Marine Biology, The University of Technology and Science, Trondheim, Norway
Thesis: ‘Skater (Pisces: Rajidae) I Norskerenna og langs norsk kontinentalskråning: utbredelse, ernæring og biologi
Advisor: Odd Aksel Bergstad
1992-1997 BSc (Cand. mag) Biology/Chemistry. The University of Technology and Science, Trondheim, Norway (Examen philosophicum from the University of Oslo, 1989)

EMPLOYMENT
Research
05/2012 -> Researcher, Institute of Marine Research, Norway
Permanent position in the Research Group; Demersal fish
04/2009-04/2012 Researcher II, University of Bergen, Norway.
Working on the Norwegian Research Council project:
• ‘The occurrence of skipped spawning and its importance for population dynamics in Northeast Arctic gadoids’. 100%
01/2006-03/2009 Researcher II, University of Bergen, Norway.
Working on two projects funded by the Norwegian Research Council:
• ‘Interactions between wild and farmed cod: non-lethal impacts of escapees on wild populations’. 60%
• ‘Timing and determination of fecundity and skipped spawning: implications for stock recruitment theory of determinate spawners’. 40%
10/2003-12/2005 Post doctoral researcher. University of Bergen, Norway.
Employed on the project ‘Habitat choice and activity in relation to hypoxia and haemoglobin genotype in fish; comparisons across populations and species’ funded by the Norwegian Research council.
2000-2003 PhD student. University of Bergen, Norway
10/2002-01/2003 Guest PhD student, Dalhousie University, Canada
(with JA Hutchings)

PUBLICATIONS

43 Fraser TWK, Vindas MA, Fjelldal PG, Winberh S, Thörnquist P, Øverli Ø, Skjæraasen JE, Hansen T, Mayer I (2015) Increased reactivity and monoamine dysregulation following stress in triploid Atlantic salmon (Salmo salar). Comprative Biochemistry & Physiology A 185:125-131

42 Skjæraasen JE, Korsbrekke K, Nilsen T, Fonn M, Kjesbu OS, Dingsør GE, Nash RDM (2015) Skipped spawning in the northeast Arctic haddock Melanogrammus aeglefinus. Marine Ecology Progress Series 526:143-155

41 Fraser TWK, Hansen T, Mayer I, Skjæraasen JE, Glover KA, Sambraus F, Fjelldal PG (2014) The effect of triploidy on vaccine side-effects in Atlantic salmon. Aquaculture 433:481-490

40 Folkvord A, Jørgensen C, Korsbrekke K, Nash RDM, Nilsen T, Skjæraasen JE (2014) Trade-offs between growth and reproduction in wild Atlantic cod. Canadian Journal of Fisheries and Aquatic Science 71:1106-1112

39 Fraser TWK, Mayer I, Hansen T, Poppe TT, Skjæraasen JE, Koppang EO, Fjelldal PG (2015) Vaccination and triploidy increase relative heart weight in farmed Atlantic salmon (Salmo salar L.). Journal of Fish Diseases 38:151-160

38 Kjesbu OS, Opdal AF, Korsbrekke K, Devine JA, Skjæraasen JE (2014) Making use of Johan Hjort’s ‘unknown’ legacy: reconstruction 1 of a 150-year coastal time series on Northeast Arctic cod (Gadus morhua) liver data reveals long-term trends in energy allocation patterns. ICES Journal of Marine Science 71:2053-2063

37 Fraser TWK, Mayer I, Skjæraasen JE, Hansen T, Fjelldal PG (2014) The plasma physiological response to Finquel® (MS 222) and Aqui-S® 1 (Isoeugenol) anaesthesia in diploid and triploid Atlantic salmon (Salmo salar L.) post-smolts. Aquaculture International 22:1347-1359

36 Kjesbu OS, Bogstad B, Devine JA, Gjøsæter H, Howell D, Ingvaldsen R, Nash RDM, Skjæraasen JE (2014) Synergies between climate and management for Atlantic cod fisheries at high latitudes. Proceedings of the National Academy of Science USA 111:3478-3483

35 Fraser TWK, Hansen T, Skjæraasen JE, Mayer I, Sambraus F, Fjelldal PG (2013) The effect of triploidy on the culture performance, deformity prevalence, and heart morphology in Atlantic salmon. Aquaculture 416-417:255-264

34 Fraser TWK, Fjelldal PG, Skjæraasen JE, Hansen T, Mayer I (2012) Triploidy alters brain morphology in pre-smolt Atlantic salmon Salmo salar: possible implications for behaviour. Journal of Fish Biology 81:2199-2212

33 Meager JJ, Mayer I, Fernö A, Skjæraasen JE, Rodewald P, Winberg S, Järvi T, Sverdrup G (2012) Multidimensionality of behavioural phenotypes in Atlantic cod, Gadus morhua. Physiology & Behaviour 106:462-470

32 Skjæraasen JE, Nash RDM, Nilsen T, Korsbrekke K, Fonn M, Kennedy J, Thorsen A, Geffen AJ, Høie H, Nedreeas K, Witthames P, Kjesbu OS (2012) Frequent skipped spawning in the world’s largest cod stock. Proceedings of the National Academy of Science USA 109:8995-8999

31 Skjæraasen JE, Nilsen T, Korsbrekke K, Fonn M, Kjesbu OS, Nash RDM (2013) Size-, energy- and stage dependent fecundity and the occurrence of atresia in the Northeast Arctic Haddock Melanogrammus aeglefinus. Fisheries Research 138:120-127

30 Meager JJ, Skjæraasen JE, Karlsen Ø, Løkkeborg S, Mayer I, Michalsen K, Nilsen T, Fernö A (2012) Environmental regulation of individual depth on a cod spawning ground. Aquatic Biology 17:211-221

29 Skjæraasen JE, Meager JJ, Heino M (2012) Secondary sexual characteristics in codfishes (Gadidae) in relation to sound production, habitat use, and social behaviour. Marine Biology Research 8:201-209

28 Skjæraasen JE, Meager JJ, Karlsen Ø, Hutchings JA, Fernö A (2011) Extreme spawning site fidelity in Atlantic cod (Gadus morhua L.). ICES Journal of Marine Science 68:1472-1477

27 Mayer I, Meager JJ, Skjæraasen JE, Rodewald P, Sverdrup G, Fernö A (2011) Domestication causes rapid changes in heart and brain morphology in Atlantic cod (Gadus morhua). Environmental Biology of Fishes 92:181-186

26 Kennedy J, Skjæraasen JE, Nash RDM, Slotte A, Geffen AJ, Kjesbu OS (2011) Evaluation of the frequency of skipped spawning in Norwegian spring-spawning herring. Journal of Sea Research 65:327-332

25 Meager JJ, Rodewald P, Domenici P, Fernö A, Järvi T, Skjæraasen JE, Sverdrup GK (2011) Behavioural responses of hatchery-reared and wild cod (Gadus morhua L.) to mechano-acoustic predator signals. Journal of Fish Biology 78:1437-1450

24 Herbert NA, Skjæraasen JE, Nilsen T, Salvanes AGV, Steffensen JF (2011) The hypoxia avoidance behaviour of juvenile Atlantic cod (Gadus morhua L.) depends on the provision and magnitude of an O2 refuge. Marine Biology 158:737-746

23 Sverdrup GK, Meager JJ, Fernö A, Skjæraasen JE, Rodewald P, Salvanes AGV, Järvi T (2011) Territorial and agonistic interactions between escaped farmed and wild cod (Gadus morhua) Aquaculture Research 42:1539-1548

22 Skjæraasen JE, Meager JJ, Karlsen Ø, Mayer I,Rudolfsen G, Dahle G, Fernø A (2010) Mating competition between farmed and wild cod Gadus morhua. Marine Ecology Progress Series 412:247-258

21 Meager JJ, Skjæraasen JE, Løkkeborg S, Fernö A (2010) Reproductive interactions between farmed and wild cod (Gadus morhua L.) in the field. Canadian Journal of Fisheries and Aquatic Sciences 67:1221-1231

20 Skjæraasen JE, Meager JJ, Hutchings JA (2010) A cost of reproduction in male Atlantic cod (Gadus morhua) Canadian Journal of Zoology 88:595-600

19 Skjæraasen JE, Hutchings JA (2010) Shifting reproductive success in a shoal of Atlantic cod, Gadus morhua L. Environmental Biology of Fishes 88:311-318

18 Skjæraasen JE, Kennedy J, Thorsen A, Nash RDM, Nilsen T, Kjesbu OS (2010) Liver energy, atresia and oocyte stage influence fecundity regulation in Northeast Arctic cod. Marine Ecology Progress Series 404:173-183

17 Kennedy J, Skjæraasen JE, Nash RDM, Thorsen A, Slotte A, Hansen T, Kjesbu OS (2010) Do capital breeders like Atlantic herring (Clupea harengus L.) exhibit sensitive periods of nutritional control on ovary development and fecundity regulation Canadian Journal of Fisheries and Aquatic Science 67:16-27

16 Skjæraasen JE, Kennedy J, Thorsen A, Fonn M, Njøes-Strand B, Mayer I, Kjesbu OS (2009) Mechanisms regulating oocyte recruitment and skipped spawning in the Northeast Arctic cod (Gadus morhua L.). Canadian Journal of Fisheries and Aquatic Science 66:1582-1596

15 Skjæraasen JE, Mayer I, Meager JJ, Rudolfsen G, Haugland T, Karlsen Ø, Kleven O (2009) Sperm characteristics and competitive ability in farmed and wild cod. Marine Ecology Progress Series 375:219-228

14 Meager JJ, Skjæraasen JE, Fernö A, Karlsen Ø,Løkkeborg S, Michalsen K, Utskot SO (2009) Vertical dynamics and reproductive behaviour of farmed and wild cod Gadus morhua. Marine Ecology Progress Series 389:233-243

13 Skjæraasen JE, Meager JJ, Karlsen Ø (2008) Expression of secondary sexual characteristics in recruit and repeat spawning farmed and wild cod. ICES Journal of Marine Science 65:1710-1716

12 Skjæraasen JE, Nilsen T, Meager JJ, Moberg O, Tronci V, Herbert NA, Johansen T, Salvanes AGV (2008) Hypoxia avoidance behaviour in cod: the effect of temperature and hemoglobin genotype. Journal of Experimental Marine Biology and Ecology 358:70-77

11 Rowe S, Hutchings JA, Skjæraasen JE, de Mestral Bezanson L (2008) Phenotypic and behavioural correlates of individual variation in male Atlantic cod reproductive success. Marine Ecology Progress Series 354:267-276

10 Hardie D, Renaud CB, Ponomarenko VP, Mukhina NV, Yaragina NA, Skjæraasen JE, Hutchings JA. (2008) The Isolation of Atlantic cod, Gadus morhua (Gadiformes), populations in northern meromictic lakes - A recurrent arctic phenomenon. Journal of Ichthyology 48:230-240

9 Rowe S, Hutchings JA, Skjæraasen JE (2007) Non-random mating in a broadcast spawner: mate size influences reproductive success in Atlantic cod (Gadus morhua). Canadian Journal of Fisheries and Aquatic Sciences 64:219-226

8 Skjæraasen JE, Rowe S, Hutchings JA (2006) Sexual dimorphism in pelvic fin length of Atlantic cod. Canadian Journal of Zoology 84: 865–870

7 Skjæraasen JE, Nilsen T, Kjesbu OS (2006) Timing and determination of potential fecundity in Atlantic cod (Gadus morhua). Canadian Journal of Fisheries and Aquatic Sciences 63: 310-320

6 Lara M, Skjæraasen JE, Utne-Palm AC, Nilsen T (2005) Recovery from handling stress in juvenile cod. Journal of Fish Biology 67: 384-391

5 Skjæraasen JE, Salvanes AGV, Karlsen Ø, Dahle R, Nilsen T, Norberg B (2004) The effect of photoperiod on sexual maturation, appetite and growth in wild Atlantic cod (Gadus morhua L.) Fish Physiology and Biochemistry 30: 163-174

4 Salvanes AGV, Skjæraasen JE, Nilsen T (2004) Sub populations of cod with different behaviour and life history strategies. Marine Ecology Progress Series 267: 241-251

3 Skjæraasen JE, Bergstad OA (2001) Notes on Raja lintea, R. Hyperborea and Bathyraja spinicauda (Pisces: Rajiade) in the Deep northeastern North Sea and on the slope of the eastern Norwegian Sea. ICES Journal of Marine Science 58: 21-28

2 Skjæraasen JE, Bergstad OA (2000) Distribution and feeding ecology of starry ray, Raja radiata, in the northeastern North Sea and Skagerrak. ICES Journal of Marine Science 57:1249-1260

1 Bjelland O, Bergstad OA, Skjæraasen JE, Meland K (2000) Trophic Ecology of deep - water species associated with the continental slope of the eastern Norwegian Sea. Sarsia 85:101-107

>40 CONFERENCE ABSTRACTS AND PRESENTATIONS