Photo of the week: Freshwater zooplankton

Department of Conservation —  10/09/2014

Most freshwater zooplankton are too small to see with the naked eye.

To bring these amazing animal-like organisms to your attention, we’ve put a 1.02 mm cladoceran (water flea) under the microscope for our photo of the week.

A 1.02 mm female Cladoceran (Water Flea). Photo copyright: Ian Gardiner. All rights reserved. Used with permission.

This beautiful, incredibly complex creature was caught on film by photographer and citizen scientist, Ian Gardiner, who kindly allowed us to share his photo.

Zooplankton are a vital component of freshwater food webs. The smallest zooplankton are eaten by the larger zooplankton which, in turn, are eaten by small fish, aquatic insects and so on.

Herbivorous zooplankton graze on phytoplankton or algae and help maintain the natural balance of algae.

“It has long been an axiom of mine that the little things are infinitely the most important.” ― Arthur Conan Doyle, The Memoirs of Sherlock Holmes

Photo: Cladoceran (Water Flea) | By Ian Gardiner | © All rights reserved

One response to Photo of the week: Freshwater zooplankton


    Water can be broadly separated into seawater and fresh water. Seawater is and is found mostly in seas and our oceans. Freshwater is located in glaciers, lakes, reservoirs, ponds, rivers, streams, wetlands as well as groundwater.