Impact of environmental change on the dynamics of freshwater zooplankton and their parasites

Zooplankton are arguably the most important trophic group in lake ecosystems. Their grazing controls algal populations, including harmful or nuisance blooms and they themselves provide food for higher trophic levels such as larger invertebrates and fish. They are instrumental for the transfer of carbon through the traditional foodweb. However, despite

many years of study of zooplankton ecology we still know little about the diversity and dynamics of their parasites. Molecular ecology has revolutionised our understanding zooplankton parasite diversity, particularly in marine systems, freshwater systems are much less well characterised. Numerous organisms infect zooplankton including Bacteria, Fungi,

Metazoans such as nematode worms and taxonomically diverse groups of protists. A single host may contain a reservoir of different parasite taxa as well as many epibionts but to what extent they may control zooplankton populations and competition between zooplankton species is unknown. Furthermore, with increased temperature and anthropogenic nutrient

inputs we do not know how zooplankton-parasite interactions may be changing. This project will reveal the black box of parasitism in zooplankton in freshwater lakes, assessing the diversity and abundance of parasites and the impact they have on individuals and populations in response to environmental change.

Monograph taken from "Die gunen Armpolypen, die geschwänzten und ungeschwänzten zackigen Wasserflöhe und eine besondere Art kleiner Wasseraale" by Jacob Christian Schaffer, published in Regensburg, Germany in 1755. The picture shows Daphnia magna visible are numerous peritrich (Ciliata) epibionts attached to the dorsal surface- a common

occurrence in Daphnia spp