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Microscopic Animals (Zooplankton)
Microscopic Animals (Zooplankton)

What are zooplankton?

The zooplankton are a community of microscopic (<3 mm)animals that are found attached to underwater plants, in sediments or suspended in the open water zone of lakes and reservoirs. Some species even move between these contrasting environments at different stages in their life cycle. Despite their size, open water zooplankton are active swimmers and are able to move throughout their environment.
Unlike phytoplankton, zooplankton cannot produce their own food and either feed on detritus, phytoplankton or other zooplankton. The zooplankton is dominated by four main groups of organisms, the protozoa, rotifers, and two groups of crustacean, the cladocerans and the copepods (often collectively known as the water fleas). Other animals important in the freshwater zooplankton include larvae of some flies eg the phantom midge, the eggs and juvenile stages of many fish, and free swimming stages of some parasites.
The zooplankton form an important link in the aquatic food web. Herbivorous species feed on the algae suspended in the open water of the lake and are themselves eaten by fish. In this way they allow the fish to exploit the new biomass produced by the algae.
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download immediately / go direct to sourcewebsite item The Virtual Copepod page This website features an introduction to the biology and ecology of copepods, including animations of their swimming behaviour.  Thematic website 
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Editors: Chief Editor; Stephen Thackeray
ID: 11867right-click for short link
added: 17 October 2003
updated: 06 December 2004
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