In 2004 northern snakeheads were discovered in the lower Potomac River. Early analysis of the age structure of the population suggested that snakeheads had been in this system since approximately 1998. In 2008 reproducing populations were discovered in the Hudson River drainage, and the Mississippi River drainage. Both state agencies are involved in massive eradication efforts to prevent snakeheads from reaching the main rivers of these drainage basins. Snakehead fish have a diet very similar to that of a Largemouth Bass. Their diet consists of crayfish, other native fish, snakes, small mammals, frogs, turtles, etc. The reason that snakeheads are bad is because they eat native fish that will not eat them. This really decreases the other fish populations and it is very hard on native ecosystems. There