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Organism Enumeration

Aquatic Plants


Algae are unicellular to multicellular plants that occur in fresh water, marine water and damp terrestrial environments. All algae possess chlorphyll, and may contain additional pigments such as fucoxanthin, or phycoerythrin. Algae are primary producers of organic matter upon which animals depend either directly or indirectly through the food chain.

Aquatic Flowering Plants

Aquatic flowering plants belong to phylum Spermatophyta characterized by possession of true roots, stems and leaves and production of seeds from flowers. This phylum contains most of the conspicuous land plants of the world. Aquatic flowering plants are almost exclusively fresh-water plants.

Aquatic Emergent Plants

Emergent plants are important components of aquatic and wetland ecosystems. They are among the primary producers, providing oxygen, food and a habitat for many life forms including invertebrates, fish, amphibians, birds and mammals. These plants are important in the nutrient cycle and the stabilization of sediments in near-shore environments.

Aquatic Animals


Zooplankton include very small animals suspended in water with limited powers of locomotion. Because of their size, they are subject to dispersal by turbulence and other water movements. Zooplankton are usually denser than water and can sink by gravity to lower depths. Although large rivers may have true plankton communities, most plankton of rivers are transient, having been washed in from a lake, pond or reservoir drainage.

Zooplankton are collected using plankton nets which are towed vertically. The sample is washed from the net and preserved in a jar containing a neutral formalin solution.

The sample is returned to the laboratory where it is examined for identification and enumeration of species of zooplankton using a microscope.

Stream Invertebrates

Stream invertebrates represent a large class of animals that can be difficult to identify. They are involved with the food web and include worms, mollusks, crustaceans, spiders, ticks, insects, centipedes, and millipedes. Collection and identification of these animals is time consuming and requires a vast knowledge of endemic species.


The fish found in the lakes and streams of Michigan are abundant and varied. Scientists from the Michigan Water Research Center are able to collect and identify fish.