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Marine Biology

, Volume 150, Issue 6, pp 1253–1263 | Cite as

Vertical distribution and mortality of Calanus finmarchicus during overwintering in oceanic waters southwest of Iceland

  • Astthor GislasonEmail author
  • Ketil Eiane
  • Pall Reynisson
Research Article

Abstract

The seasonal vertical distribution and the predatory regime encountered by Calanus finmarchicus were studied along a transect across the Reykjanes Ridge in the oceanic area southwest of Iceland from data collected during four cruises between November 1996 and June 1997. The mortality for the overwintering period was estimated using linear regressions of density estimates from November 1996 to April 1997. In addition, we also estimated the mortality of the oldest population stages (C4 and older) in April and June by applying the vertical table method. During winter (November/December–January/February), the animals mainly resided at a depth of ∼300–1,500 m in the water of Atlantic origin. Ascent to upper layers took place mainly during March and April, and continued until May. During all cruises, continuous deep-scattering layers were observed, mainly within the range of 400–500 m to 700–800 m depth. Based on sampling with a Harstad pelagic trawl in April, the scattering was mainly ascribed to jellyfish (mainly Periphylla periphylla), small mesopelagic oceanic fishes (several species but Benthosema glaciale and Maurolicus muelleri were most abundant), euphausiids (mainly Meganyctiphanes norvegica) and shrimps (mainly Sergestes arcticus). These species may represent a predatory threat to overwintering C. finmarchicus. From November to April, daily per capita mortality rates were estimated to be (mean ± 95% CL) 0.004 ± 0.0028 for the total data set, and 0.004 ± 0.0033 and 0.004 ± 0.0023 (day-1) for the Iceland Basin and Irminger Basin, respectively. Mortality rates were higher later in life (mean ± 95% CL) for C5/females (0.13 ± 0.044) and C5/males (0.19 ± 0.051) than for C4/C5 (0.00 ± 0.035) when averaged over all samples taken in April and June 1997. We discuss how the observed distribution and mortality rates of overwintering C. finmarchicus might be related to predatory regime.

Keywords

Mesopelagic Fish Reykjanes Ridge Predatory Regime Iceland Basin Scattering Layer 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgements

We are grateful to the crew on the RV “Bjarni Sæmundsson” and colleagues at the Marine Research Institute for their help in the sampling. Further, we should like to thank A. R. Bodvarsdottir and H. Petursdottir for analysing the zooplankton samples, and H. Valdimarsson, J. Morthensen, and S.-A. Malmberg for help with the interpretation of the physical data. This study was funded by the European commission through the TASC project (Contract No. MAS3-CT95–0039) and the Icelandic Republic Fund. A substantial part of this paper was written during a 2-month visit of the first author to the Woods Hole Oceanographic Institution on the invitation of Dr. Peter Wiebe whose hospitality is gratefully acknowledged.

References

  1. van Aken HM, de Boer CJ (1995) On the synoptic hydrography of intermediate and deep water masses in the Iceland Basin. Deep Sea Res 42:165–189CrossRefGoogle Scholar
  2. Aksnes DL, Ohman MD (1996) A vertical life table approach to zooplankton mortality estimation. Limnol Oceanogr 41:1461–1469CrossRefGoogle Scholar
  3. Aksnes D, Miller CB, Ohman MD, Wood S (1997) Estimation techniques used in studies of copepod population dynamics—a review of underlying assumptions. Sarsia 82:279–296CrossRefGoogle Scholar
  4. Astthorsson OS, Gislason A (1999) Inter-annual variation in abundance and development of Calanus finmarchicus in Faxaflói, West Iceland. Rit Fiskideild 16:131–140Google Scholar
  5. Astthorsson OS, Hallgrímsson I, Jónsson GS (1983) Variations in zooplankton densities in Icelandic waters in spring during the years 1961–1982. Rit Fiskideild 7:73–113Google Scholar
  6. Auel H (1999) The ecology of Arctic deep-sea copepods (Euchaeta and Aetideidae). Aspects of their distribution, trophodynamics and effect on the carbon flux. Ber Polarforsch 319:1–97Google Scholar
  7. Bagøien E, Kaartvedt S, Aksnes DL, Eiane K (2001) Vertical distribution and mortality of overwintering Calanus. Limnol Oceanogr 46:1494–1510CrossRefGoogle Scholar
  8. Blindheim J, Buch E, Fogelqvist E, Tanhua T, Østerhus S (1996) The R/V Johan Hjort 1994 NORDIC WOCE cruice: on hydrography and tracers. ICES CM 1996/O: 20, p 26Google Scholar
  9. Campbell RG, Wagner MM, Teegarden GJ, Boudreau CA, Durbin EG (2001) Growth and development rates of the copepod Calanus finmarchicus reared in the laboratory. Mar Ecol Prog Ser 221:161–183CrossRefGoogle Scholar
  10. Colebrook JM (1985) Continuous plankton records: overwintering and annual fluctuations in the abundance of zooplankton. Mar Biol 84:261–265CrossRefGoogle Scholar
  11. Eiane K, Ohman MD (2004) Stage specific mortality of Calanus finmarchicus, Pseudocalanus elongatus and Oithona similis on Fladen Ground, North Sea, during a spring bloom. Mar Ecol Prog Ser 268:183–193CrossRefGoogle Scholar
  12. Eiane K, Aksnes DL, Ohman MD, Martinussen MB (2002) Stage-specific mortality of Calanus spp. under different predation regimes. Limnol Oceanogr 47:636–645CrossRefGoogle Scholar
  13. Fiksen Ø, Carlotti F (1998) A model of optimal life history and diel vertical migration in Calanus finmarchicus. Sarsia 83:129–147CrossRefGoogle Scholar
  14. Fiksen Ø, Giske J (1995) Vertical distribution and population dynamics of copepods by dynamic optimization. ICES J Mar Sci 52:483–503CrossRefGoogle Scholar
  15. Foote KG, Knudsen HP, Korneliussen RJ, Nordbö PE, Röang K (1991) Postprocessing system for echo sounder data. J Acoust Soc Am 90:38–38Google Scholar
  16. Gaard E (1994) Advection and seasonal development of the copepod Calanus finmarchicus of the Faroe Plateau, ICES CM 1994/L,21, p 16Google Scholar
  17. Gislason A (2003) Life-cycle strategies and seasonal migrations of oceanic copepods in the Irminger Sea. Hydrobiologia 503:195–209CrossRefGoogle Scholar
  18. Gislason A (2005) Seasonal and spatial variability in egg production and biomass of Calanus finmarchicus around Iceland. Mar Ecol Prog Ser 286:177–192CrossRefGoogle Scholar
  19. Gislason A, Astthorsson OS (1995) Seasonal cycle of zooplankton southwest of Iceland. J Plankton Res 17:1959–1976CrossRefGoogle Scholar
  20. Gislason A, Astthorsson OS (1996) Seasonal development of Calanus finmarchicus along an inshore–offshore gradient southwest of Iceland. Ophelia 44:71–84CrossRefGoogle Scholar
  21. Gislason A, Astthorsson OS (2000) Winter distribution, ontogenetic migration and rates of egg production of Calanus finmarchicus southwest of Iceland. ICES J Mar Sci 57:1727–1739CrossRefGoogle Scholar
  22. Gjøsæter J (1981) Life history and ecology of Maurolicus muelleri (Gonostomatidae) in Norwegian waters. Fiskeridir Skr (Ser Havunders) 17:109–131Google Scholar
  23. Hallgrímsson I (1954) Noen bemerkninger om Faxaflóis hydrografi og zooplanktonbestand in 1948. (Aspects of the hydrography and zooplankton of Faxafloi Bay during 1948, in Norwegian). M.Sc. dissertation, University of Oslo, Norway, p 87Google Scholar
  24. Hansen B (1985) The circulation of the northern part of the Northeast Atlantic. Rit Fiskideild 9:110–126Google Scholar
  25. Hansen B, Østerhus S (2000) North Atlantic–Nordic Seas exchanges. Prog Oceanogr 45:109–208CrossRefGoogle Scholar
  26. Hansen B, Stefánsson U, Svendsen E (1998) Icelandic, Faroe and Norwegian coasts. Coastal segment (21, E). In: Robinson AR, Brink KH (eds) The Sea, vol. 11. Wiley, NY, pp 733–758Google Scholar
  27. Hansen BW, Hygum BH, Brozek M, Jensen F, Rey C (2000) Food web interactions in a Calanus finmarchicus dominated pelagic ecosystem—a mesocosm study. J Plankton Res 22:569–588CrossRefGoogle Scholar
  28. Heath MR (1999) The ascent migration of Calanus finmarchicus from overwintering depths in the Faroe-Shetland Channel. Fish Oceanogr 8:84–99CrossRefGoogle Scholar
  29. Heath MR, Fraser JG, Gislason A, Hay SJ, Jónasdóttir SH, Richardson K (2000) Winter distribution of Calanus finmarchicus in the northeast Atlantic. ICES J Mar Sci 57:1628–1635CrossRefGoogle Scholar
  30. Heath MR, Boyle PR, Gislason A, Gurney WSC, Hay SJ, Head EJH, Holmes S, Ingvarsdóttir A, Jónasdóttir SH, Lindeque P, Pollard RT, Rasmussen J, Richards K, Richardson K, Smerdon G, Speirs D (2004) Comparative ecology of over-wintering Calanus finmarchicus in the northern North Atlantic, and implications for life-cycle patterns. ICES J Mar Sci 61:698–708CrossRefGoogle Scholar
  31. Hirche H-J (1998) Dormacy in three Calanus species (C. finmarchicus, C. glacialis and C. hyperboreus) from the North Atlantic. Arch Hydrobiol Spec Issues Advanc Limnol 52:359–369Google Scholar
  32. Ingvarsdóttir A, Houlihan DF, Heath MR, Hay SJ (1999) Seasonal changes in respiration rates of copepodite stage V Calanus finmarchicus (Gunnerus). Fish Oceanogr 8:73–83CrossRefGoogle Scholar
  33. Irigoien X (2000) Vertical distribution and population dynamics of Calanus finmarchicus at station India (59°N, 19°W) during the passage of the great salinity anomaly, 1971 to 1975. Deep Sea Res 47:1–26CrossRefGoogle Scholar
  34. Jónasdóttir SH (1999) Lipid content of Calanus finmarchicus during overwintering in the Faroe-Shetland Channel. Fish Oceanogr 8:61–72CrossRefGoogle Scholar
  35. Kaartvedt S (1996) Habitat preference during overwintering and timing of seasonal vertical migration of Calanus finmarchicus. Ophelia 44:145–156CrossRefGoogle Scholar
  36. Knudsen HP (1990) The Bergen echo integrator: an introduction. J Cons int Explor Mer 47:167–174CrossRefGoogle Scholar
  37. Magnússon J (1996) The deep scattering layers in the Irminger Sea. J Fish Biol 49:182–191CrossRefGoogle Scholar
  38. Malmberg S-A (1978) Seasonal means of temperature and salinity in the shelf area in Háfadjúp and across Selvogsbanki in 1971–1975. Surtsey Res Prog Rep 7:60–62Google Scholar
  39. McLaren IA (1963) Effects of temperature on growth of zooplankton, and the adaptive value of vertical migration. J Fish Res Bd Can 20:685–727CrossRefGoogle Scholar
  40. McLaren IA (1974) Demographic strategy of vertical migration by a marine copepod. Am Nat 108:91–102CrossRefGoogle Scholar
  41. Melle W, Ellertsen B, Skjoldal HR (2004) Zooplankton: the link to higher trophic levels. In: Skjoldal HR, Sætre R, Færnö A, Misund OA, Röttingen I (eds) The Norwegian sea ecosystem. Tapir Academic Press, Trondheim pp 137–202Google Scholar
  42. Mortensen J (1997) Satellite altimetry and circulation in the Denmark Strait and adjacent seas. Ph.D. Thesis, Niels Bohr Institute, Copenhagen, p 169Google Scholar
  43. Motoda S (1959) Devices of simple plankton apparatus. Mem Fac Fish Hokkaido Univ 7:73–94Google Scholar
  44. Mullin MM, Brooks ER (1970) Production of the planktonic copepod Calanus helgolandicus. Bull Scripps Inst Oceanogr 17:89–103Google Scholar
  45. Nichols JH, Thompson AB (1991) Mesh selection of copepodite and nauplius stages of four calanoid copepod species. J Plankton Res 13:661–171CrossRefGoogle Scholar
  46. Nisbet RM, Wood SN (1996) Estimation of copepod mortality rates. Ophelia 44:157–170CrossRefGoogle Scholar
  47. Ohman MD, Runge JA, Durbin EG, Field DB, Niehoff B (2002) On birth and death in the sea. Hydrobiologia 480:55–68CrossRefGoogle Scholar
  48. Ohman MD, Eiane K, Durbin EG, Runge JA, Hirche H-J (2004) A comparative study of Calanus finmarchicus mortality patterns at five localities in the North Atlantic. ICES J Mar Sci 61:687–697CrossRefGoogle Scholar
  49. Østvedt OJ (1955) Zooplankton investigations from Weathership M in the Norwegian Sea, 1948–1949. Hvalrd Skr 40:1–93Google Scholar
  50. Planque B, Fromentin J-M (1996) Calanus and environment in the eastern North Atlantic. I. Spatial and temporal patterns of C. finmarchicus and C. helgolandicus. Mar Ecol Prog Ser 134:101–109CrossRefGoogle Scholar
  51. Schmitz Jr WJ, McCartney MS (1993) On the North Atlantic circulation. Rev Geophys 31:29–49CrossRefGoogle Scholar
  52. Torgersen T, Kaartvedt S, Melle W, Knutsen T (1997) Large scale distribution of acoustical scattering layers at the Norwegian continental shelf and the eastern Norwegian Sea. Sarsia 82:87–96CrossRefGoogle Scholar
  53. Valdimarsson H, Malmberg S-A (1999) Near-surface circulation in Icelandic waters derived from satellite tracked drifters. Rit Fiskideild 16:23–39Google Scholar
  54. Yen J (1983) Effects of prey concentration, prey size, predator life stage, predator starvation, and season on predation rates of the carnivorous copepod Euchaeta elongata. Mar Biol 75:69–77CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  1. 1.Marine Research InstituteReykjavikIceland
  2. 2.University Courses on SvalbardLongyearbyenNorway

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