Ecosystems

, Volume 11, Issue 3, pp 490–503

Invasive Predator, Bythotrephes, has Varied Effects on Ecosystem Function in Freshwater Lakes

Authors

    • Department of BiologyQueen’s University
    • Department of Ecology & Evolutionary BiologyUniversity of Toronto
  • Shelley E. Arnott
    • Department of BiologyQueen’s University
Article

DOI: 10.1007/s10021-008-9137-0

Cite this article as:
Strecker, A.L. & Arnott, S.E. Ecosystems (2008) 11: 490. doi:10.1007/s10021-008-9137-0

Abstract

Bythotrephes longimanus is an invertebrate predator that has invaded the North American Great Lakes and a number of inland lakes, where it preys on crustacean zooplankton. We examined the effect of Bythotrephes on two measures of ecosystem function during a four-month observational study of freshwater lakes on the boreal shield. Bythotrephes-invaded lakes had significantly lower epilimnetic zooplankton abundance and production compared to reference lakes. On average, Bythotrephes consumed 34% of zooplankton production when it was present in lakes. There was some evidence of changes in the timing of zooplankton production, as well as shifts to cooler, less productive habitats, which may lessen the overall effect of the invader on the transfer of energy to higher trophic levels. We experimentally demonstrated a weak trophic cascade where invader predation reduced zooplankton biomass, and subsequently increased phytoplankton growth. However, the response was small in magnitude and not biologically relevant at the whole lake-scale. The most conspicuous effect of Bythotrephes that we measured was a diversion of energy away from native predators at higher trophic levels.

Keywords

invasive species ecosystem function crustacean zooplankton Bythotrephes freshwater lakes secondary production zooplankton grazing

Supplementary material

Copyright information

© Springer Science+Business Media, LLC 2008