the National Aeronautics and Space Administration

“ The diversity and the population of these organisms reflect how healthy or unhealthy the River may be. Some organisms that are sensitive to pollution are mayflies, stoneflies, riffle beetles, and some caddisflies. A healthy population of these organisms indicates nonpolluted waters. However, if a river contains a large number of pollution tolerant organisms, like sludge worms and leeches, along with few or no pollution sensitive species, then the river water may very well be polluted. ”

“ They are small, bottom dwelling organisms that can be seen with the naked eye. In the Cuyahoga River most of the bethnic macroinvertebrates are stonefly nymphs, mayfly nymphs, caddisfly larvae, midge larvae and other types of aquatic insects. These aquatic insects follow three stages in their incomplete metamorphosis. The three stages of life are egg, nymph, and adult. The winged adult version of the dragonfly is a common sight along the Cuyahoga River. The River's fish population is always increasing. Good size walleye, northern pike, and bass are found in the Upper River. ”

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