The Grass carp tolerates some salt, high temperature ranges, and low oxygen. It also survives better than native fish in polluted waters. Grass carp, as you might guess from the name, eat grass and other underwater plants, but will also eat insects and decaying plants. They are capable of consuming up to 40% of their body weight every day. Because of their amazing ability to eat, this species was brought to the US in 1963 for research on controlling aquatic plants. They weren't carefully monitored and were found in the Missouri and Mississippi rivers in Arkansas by the 1970s. Because they reproduce quickly and eat the plants that other native species depend on, they are considered an invasive fish but are already established in most of the Mississippi River (map).
Maximum length is approximately 59 inches
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Did You Know?
The river is so shallow at Lake Itasca that children can walk across the Mississippi. Between Governor Nicholls Wharf and Algiers Point in New Orleans, the Mississippi is more than 200 feet deep.