Macro Invertebrates of the Red River
MacroInvertebrates PicMacro invertebrates are organisms without a backbone that you can see with your naked eye. Invertebrates include animals such as sponges, jellyfish, worms, mollusks, crustaceans and insects.

Many insects undergo complete metamorphosis. They have four distinct stages: egg, larva, pupa, and adult. Most aquatic insects undergo incomplete metamorphosis. This means that the egg hatches into a nymph and then it develops into a functional adult. A nymph resembles the adult but lacks wings. Aquatic insects spend the first part of their life cycle in the water and emerge as adults.

Aquatic invertebrates are good indicators of water quality. This is because they are sensitive to change in their environment and cannot escape during these changes. Another reason they make good indicators is because they can easily be collected for samples and studies. Some of the invertebrates that are sensitive to pollution include mayflies, stoneflies, caddisflies, and riffle beetles. Mayflies (Ephemeroptera), stoneflies (Plecoptera) and caddisflies (Trichoptera) are also known as the E.P.T. inverts because they are the top three indicator organisms. Midges and leeches are examples of invertebrates that are tolerant to a polluted environment.




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