Spotlight On: The Plankton - plants and animals that are free-floating in lakes, at the mercy of currents and waves, are called plankton. The microscopic plants are called phytoplankton and form the base of the food web by fixing the sun's energy into organic carbon. The microscopic animals are called zooplankton and graze on the phytoplankton, transferring energy and materials up the food web. The energy route from phytoplankton to zooplankton to fish is called the pelagic (or open water) pathway. Phytoplankton are collected by towing a fine mesh net (openings of ~50 µm or 50 millionths of a meter). To collect zooplankton, we use a larger net (openings of ~ 150 µm) and lower the net much deeper. The zooplankton spend the daylight hours in the darkened depths of the lake (to avoid fish predation), migrating to the surface at night to graze on the phytoplankton
Spotlight On: The Plankton -
