Polar Biology

, Volume 36, Issue 10, pp 1537–1542 | Cite as

The nucleus of the lapillar otolith discriminates the early life stages of Boreogadus saida and Arctogadus glacialis

  • Caroline BouchardEmail author
  • Dominique Robert
  • R. John Nelson
  • Louis Fortier
Short Note


Polar cod (Boreogadus saida) and ice cod (Arctogadus glacialis) are sympatric on continental shelves of the Arctic Ocean. The larvae and early juveniles of the two species are similar, and discrimination based on morphology and pigmentation is uncertain. We present a discrimination criterion based on the difference in lapillus nucleus size between genetically identified B. saida (n = 441, 4.2–55.0 mm standard length) and A. glacialis (n = 82, 8.6–45.5 mm). The product of the shortest and longest diameters of the nucleus (SN × LN) was 58 % larger in A. glacialis than in B. saida. The logistic regression (Ln[p/(1 − p)] = 0.02687SN × LN − 17.5466), where p is the probability that the fish is A. glacialis, correctly reassigned 501 of the 523 fishes (96 %) used to build the model to their genetically determined species (99 % of B. saida and 80 % of A. glacialis). The same regression correctly classified 97 % of 189 fish sampled in 2002 and 2003 and not used in building the model (99 % of B. saida and 89 % of A. glacialis).


Arctic gadids Ice cod Polar cod Otolith microstructure Species identification 



We thank the numerous colleagues who contributed to field sampling, as well as the crew of the research icebreaker CCGS Amundsen. H. Cloutier, S. Puckett, and E. Rondeau provided technical assistance. S. L. Talbot at the Alaska Science Center, U.S. Geological Survey, Anchorage, Alaska, USA, designed the primers used in the amplification of Cytb. This study is a contribution to the programs of Québec-Océan at Université Laval, the Network of Centres of Excellence ArcticNet, and the Canada Research Chair on the response of marine arctic ecosystems to climate warming.

Supplementary material

300_2013_1371_MOESM1_ESM.pdf (394 kb)
Supplementary material 1 (PDF 394 kb)


  1. Belkhir K, Borsa P, Chikhi L, Raufaste N, Bonhomme F (2004) GENETIX 4.05, logiciel sous Windows TM pour la génétique des populations. Laboratoire Génome, Populations, Interactions, CNRS UMR 5171, Université de Montpellier II, MontpellierGoogle Scholar
  2. Bouchard C, Fortier L (2008) Effects of polynyas on the hatching season, early growth and survival of polar cod Boreogadus saida in the Laptev Sea. Mar Ecol Prog Ser 355:247–256CrossRefGoogle Scholar
  3. Bouchard C, Fortier L (2011) Circum-arctic comparison of the hatching season of polar cod Boreogadus saida: a test of the freshwater winter refuge hypothesis. Prog Oceanogr 90:105–116CrossRefGoogle Scholar
  4. Campana SE, Neilson JD (1985) Microstructure of fish otoliths. Can J Fish Aquat Sci 42:1014–1032CrossRefGoogle Scholar
  5. D’Alessandro E, Sponaugle S, Cowen R (2013) Selective mortality during the larval and juvenile stages of snappers (Lutjanidae) and great barracuda Sphyraena barracuda. Mar Ecol Prog Ser 474:227–242CrossRefGoogle Scholar
  6. Fortier L, Sirois P, Michaud J, Barber D (2006) Survival of Arctic cod larvae (Boreogadus saida) in relation to sea ice and temperature in the Northeast Water Polynya (Greenland Sea). Can J Fish Aquat Sci 63:1608–1616CrossRefGoogle Scholar
  7. Høie H, Folkvord A, Johannessen A (1999) Maternal, paternal and temperature effects on otolith size of young herring (Clupea harengus L.) larvae. J Exp Mar Biol Ecol 234:167–184CrossRefGoogle Scholar
  8. Madsen M, Fevolden S-E, Christiansen J (2009) A simple molecular approach to distinguish between two Arctic gadoid fishes Arctogadus glacialis (Peters, 1874) and Boreogadus saida (Lepechin, 1774). Polar Biol 32:937–939CrossRefGoogle Scholar
  9. Maneja R, Frommel A, Geffen A, Folkvord A, Piatkowski U, Chang M, Clemmesen C (2013) Effects of ocean acidification on the calcification of otoliths of larval Atlantic cod Gadus morhua. Mar Ecol Prog Ser 477:251–258CrossRefGoogle Scholar
  10. Michaud J, Fortier L, Rowe P, Ramseier R (1996) Feeding success and survivorship of Arctic cod larvae, Boreogadus saida, in the Northeast Water Polynya (Greenland Sea). Fish Oceanogr 5:120–135CrossRefGoogle Scholar
  11. Nelson RJ, Bouchard C, Madsen M, Praebel K, Rondeau E, Schalburg K, Leong J, Jantzen S, Sandwith Z, Puckett S, Messmer A, Fevolden S-E, Koop B (2013) Microsatellite loci for genetic analysis of the arctic gadids Boreogadus saida and Arctogadus glacialis. Conserv Genet Resour 5:445–448CrossRefGoogle Scholar
  12. Raventos N, Macpherson E (2005) Effect of pelagic larval growth and size-at-hatching on post-settlement survivorship in two temperate labrid fish of the genus Symphodus. Mar Ecol Prog Ser 285:205–211CrossRefGoogle Scholar
  13. Scherrer B (2009) Biostatistique, 2e édn, vol 2. Gaëtan Morin, 592 ppGoogle Scholar
  14. Sekerak AD (1982) Young-of-the-year cod (Boreogadus) in Lancaster Sound and western Baffin Bay. Arctic 35:75–97Google Scholar
  15. Suzuki KW (2013) Identification guide to Arctic ichthyoplankton.
  16. Thanassekos S, Fortier L (2012) An individual based model of Arctic cod (Boreogadus saida) early life in Arctic polynyas: I. Simulated growth in relation to hatch date in the northeast water (Greenland Sea) and the north water (Baffin Bay). J Mar Syst 93:25–38CrossRefGoogle Scholar
  17. Thanassekos S, Robert D, Fortier L (2012) An individual based model of Arctic cod (Boreogadus saida) early life in Arctic polynyas: II. Length-dependent and growth-dependent mortality. J Mar Syst 93:39–46CrossRefGoogle Scholar
  18. Vigliola V, Meekan MG (2002) Size at hatching and planktonic growth determine post-settlement survivorship of a coral reef fish. Oecologia 131:89–93CrossRefGoogle Scholar
  19. Walkusz W, Paulic JE, Williams WJ, Kwasniewski S, Papst MH (2011) Distribution and diet of larval and juvenile Arctic cod (Boreogadus saida) in the shallow Canadian Beaufort Sea. J Mar Syst 84:78–84CrossRefGoogle Scholar
  20. Welch HE, Bergmann MA, Siferd TD, Martin KA, Curtis MF, Crawford RE, Conover RJ, Hop H (1992) Energy flow through the marine ecosystem of the Lancaster Sound region, Arctic Canada. Arctic 45:343–357Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Caroline Bouchard
    • 1
    Email author
  • Dominique Robert
    • 1
    • 3
  • R. John Nelson
    • 2
  • Louis Fortier
    • 1
  1. 1.Département de Biologie, Québec-OcéanUniversité LavalQuébecCanada
  2. 2.Department of BiologyUniversity of VictoriaVictoriaCanada
  3. 3.Centre for Fisheries Ecosystems Research, Fisheries and Marine InstituteMemorial UniversitySt. John’sCanada

Personalised recommendations