Step 1 : Introduction to the question "Why were Asian carp introduced into the U.S.?"
...Among the aquatic scene, many species have a dirty name, and that list includes various types of fish known as Asian carp. These fish, first introduced into the U.S. in the 1970s to combat weed and parasite issues, are silver carp, black carp, grass carp and bighead carp. Somehow, the non-native species made their way into the Mississippi River, working their way up as far as Minnesota. Once Asian carp reach an area, they out-compete native fish for space and food, sometimes pushing native species out. And you thought having your in-laws over for a weekend was bad. Source: National Park Service
