Aquatic Ecology

, Volume 44, Issue 1, pp 233–242

Does the nutrient stoichiometry of primary producers affect the secondary consumer Pleurobrachia pileus?

  • Katherina L. Schoo
  • Nicole Aberle
  • Arne M. Malzahn
  • Maarten Boersma
Article

DOI: 10.1007/s10452-009-9265-4

Cite this article as:
Schoo, K.L., Aberle, N., Malzahn, A.M. et al. Aquat Ecol (2010) 44: 233. doi:10.1007/s10452-009-9265-4

Abstract

We investigated whether phosphorus limitations of primary producers propagate upwards through the food web, not only to the primary consumer level but also onto the secondary consumers’ level. A tri-trophic food chain was used to assess the effects of phosphorus-limited phytoplankton (the cryptophyte Rhodomonas salina) on herbivorous zooplankters (the copepod Acartia tonsa) and finally on zooplanktivores (the ctenophore Pleurobrachia pileus). The algae were cultured in phosphorus-replete and phosphorus-limited media before being fed to two groups of copepods. The copepods in turn were fed to the top predator, P. pileus, in a mixture resulting in a phosphorus-gradient, ranging from copepods having received only phosphorus-replete algae to copepods reared solely on phosphorus-limited algae. The C:P ratio of the algae varied significantly between the two treatments, resulting in higher C:P ratios for those copepods feeding on phosphorus-limited algae, albeit with a significance of 0.07. The differences in the feeding environment of the copepods could be followed to Pleurobrachia pileus. Contrary to our expectations, we found that phosphorus-limited copepods represented a higher quality food source for P. pileus, as shown by the better condition (expressed as nucleic acid content) of the ctenophore. This could possibly be explained by the rather high C:P ratios of ctenophores, their resulting low phosphorus demand and relative insensitivity to P deficiency. This might potentially be an additional explanation for the observed increasing abundances of gelatinous zooplankton in our increasingly phosphorus-limited coastal seas.

Keywords

Phosphorus limitationCtenophoresEcological stoichiometryMarine food websGelatinous zooplanktonTrophic transfer

Copyright information

© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  • Katherina L. Schoo
    • 1
    • 2
  • Nicole Aberle
    • 1
  • Arne M. Malzahn
    • 1
  • Maarten Boersma
    • 1
    • 3
  1. 1.Alfred-Wegener-Institut für Polar- und MeeresforschungBiologische Anstalt HelgolandHelgolandGermany
  2. 2.Leibniz Institute of Marine SciencesIFM-GeomarKielGermany
  3. 3.GKSS-Research CentreInstitute for Coastal ResearchGeesthachtGermany