Organisms of the Cuyahoga River


-- The diverse habitat of the Cuyahoga River provides a home for a variety of different species. Within the river itself there are fish, amphibians,and many types of macroinvertebrates. One type of macroinvertabrates are benthic macroinvertebrates. 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. Some of the fish found in the section of the river flowing through Cuyahoga County are the eastern gizzard shad, freshwater drum, common carp, northern hog sucker, goldfish, quillback carpsucker,golden shiner, northern largemouth blackbass, northern bluegill sunfish, green sunfish, warmouth sunfish, grass pickerel, northern pike, yellow perch, channel catfish, black bullhead, white perch, different species of minnow, and many others. Many non-aquatic organisms also live around the River's banks. If you travel along the Cuyahoga, especially the upper section, which is a designated scenic river, you are likely to find a beaver making a dam. You can also find great blue heron, turtles, ducks, geese, and many other forms of wildlife.

Northern hog sucker


Water quality indicators

-- Benthic macroinvertebrates are good indicators of water quality because they are sensitive to the River's changes, they cannot escape the River's pollution, they are easily collected and they have a one year lifespan. 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. Fish can also be used as indicators of water quality. Pollution sensitive species of fish found in the Cuyahoga River are the common shiner, hornyhead chub, river chub, rock bass, log perch, yellow bullhead, blutnose minnow, and the spotted sucker. Pollution tolerant and intermediate species include the white sucker, pumpkinseed sunfish, the spotted sucker, goldfish, common carp, white perch, and gizzard shad.


The effect of Pollution on Organisms

-- The Cuyahoga River's pollution has a strong effect on the organisms living in and around it. For example, fish caught along the entire length of the River below the Edison Dam were found to have elevated levels of PCB's (polychlorinatedbenzene)and certain pesticides. However this level of pollutants does not exceed the national standard and therefore there is no fish contamination advisory. The percentage of fish found in the Cuyahoga River that have tumors and/or external problems has decreased since 1984. But it is interesting to note that the percentage of fish having tumors and/or external problems is higher in the urbanized area of the Cuyahoga River's watershed as compared to the non-urban areas of the watershed.

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