Advertisement

Metabolism of Antarctic Krill, Euphausia superba, and Its Tropho-Dynamic Implications

  • R. Y. George
Conference paper

Summary

The paper focuses on the nitrogenous excretion of various ontogenetic stages of the Antarctic Krill, Euphausia superba, with particular emphasis on contributions of ammonia to the ambient marine environment. As a reflection of a high feeding rate and elevated metabolism, Krill exhibit enhanced catabolic activity under favourable feeding conditions. Within various stages of Krill, ammonia excretion rate averages >260μg NH3 g−1 (dw) h−1. Consequently, a very large quantity of ammonia is released to the ambient environment from Krill swarms in which density can attain 1000 individuals m3. Swarms of significant magnitude, such as the great patches of Krill commonly encountered northwest of Elephant Island and the vast aggregations of Krill in the neritic waters of the Bransfield Strait in the Antarctic Peninsula region, may exert a profound impact on biological processes. The tropho-dynamic implications of the production of ammonia by Krill are discussed in terms of an hypothesis dealing with the positive feed-back of ammonia production by zooplankton to the Antarctic marine ecosystem.

Keywords

Antarctic Peninsula Ontogenetic Stage Ammonia Excretion Ammonia Production Antarctic Krill 
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.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Antezana Ti; Ray K (1984) Feeding of Euphausia superbain a swarm north of the Elephant Island. J Crust Biol 4: 142–155Google Scholar
  2. Biggs DC (1982) Zooplankton Excretion and NH4+ Cycling in Near-Surface Waters of the Southern Ocean I. Ross Sea, Austral Summer 1977–1978. Polar Biol 1: 55–67CrossRefGoogle Scholar
  3. Boyd CM; Heyraud M; Boyd CN (1984) Feeding of the Antarctic Krill Euphausia superba. J. Crust Biol 4: 123–141Google Scholar
  4. Dugdale RC; Goering JJ (1967) Uptake of New and Regenerated Forms of Nitrogen in Primary Productivity. Limnon Oceanogr 12: 196–206CrossRefGoogle Scholar
  5. El-Sayed SZ (1968) On the Productivity of the Southwest Atlantic Ocean and the Waters West of the Antarctic Peninsula: In: Llano GA, Schmitt WL (eds) Biology of the Antarctic Seas III, Antarctic Research Series II. American Geophysical Union, Washington, DC pp 15–47Google Scholar
  6. Epply RW; Rogers JN; McCarthy JJ (1969) Half Saturation Constants for Uptake of Nitrate and Ammonium by Marine Phytoplankton. Limnol Oceanogr 14: 912–920CrossRefGoogle Scholar
  7. George RY (1977) Dissimilar and Similar Trends in Antarctic and Arctic Marine Benthos: In: Dunbar MJ (ed) Polar Oceans. Arctic Institute of North America, Calgary, Alberta pp 391–407Google Scholar
  8. George RY (1984) Ontogenetic Adaptions in Growth and Respiration of Euphausia superbain Relation to Temperature and Pressure. J Crust Biol 4: 252–262CrossRefGoogle Scholar
  9. George RY; Fields JR (1984) Ammonia Excretion in the Antarctic Krill Euphausia superbain Relation to Starvation and Ontogenetic Stages. J Crust Biol 4: 263–272Google Scholar
  10. Hamner W (1984) Aspects of Schooling in Euphausia superba. J Crust Biol 4: 67–74Google Scholar
  11. Hirsch HJ (1983) Excretion and Respiration of the Antarctic Krill Euphausia Superba. Polar Biol 1: 205–209CrossRefGoogle Scholar
  12. Holm-Hansen O, El-Sayed SZ; Franceschini GA; Cuhel RL (1977) Primary Production and the Factors Controlling Phytoplankton Growth in the Southern Ocean. In: Llano GA (ed) Adaptations Within Antarctic Ecosystems. Gulf Publishing Co, Houston, Texas pp 11–50Google Scholar
  13. Holm-Hansen O; Huntley M (1984) Feeding Requirements of Krill in Relation to Food Sources. J Crust Biol 4: 156–173Google Scholar
  14. Ikeda I (1984) Sequence in Metablic Rates and Elemental Composition (C,N,P) During the Development of Euphausia superbaand Estimated Food Requirements During its Life Span. J Crust Biol 4: 273–284Google Scholar
  15. Johnson M; Macaulay M; Biggs D (1984) Respiration and Excretion Within a Mass Aggregation of Euphausia superba: Implications for Krill Distribution. J Crust Biol 4: 174–184Google Scholar
  16. Kils U (1979) Performance of Antarctic Krill Euphausia superbaat Different Levels of Oxygen Saturation. Meeresforschung 27: 35–48Google Scholar
  17. Macaulay MC; English TS; Mathiesen DA (1984) Acoustic Characterization of Antarctic Krill (Euphausia superba)Swarms from the Elephant Island and Bransfield Strait. J Crust Biol 4 (Spec No. 1): 16–44Google Scholar
  18. Marr J (1962) The Natural History and Geography of the Antarctic Krill (Eupausia superbaDana). Discovery Re 32: 33–464Google Scholar
  19. Morris D (1984) Filtration Rates of Euphausia superba: Under or Over Estimates? J Crust Biol 4: 185–197Google Scholar
  20. Nelson SG; Knight AW; Li WH (1977) The metabolic cost of food Utilization and Ammonia Production by Juvenile Macrobrachium rosenbergii(Crustacea: Paloemonidae). Comp Biochem Physiol 57A: 67–72CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1985

Authors and Affiliations

  • R. Y. George
    • 1
  1. 1.Institute for Marine Biomedical ResearchUniversity of North Carolina at WilmingtonWilmingtonUSA

Personalised recommendations