Pool 2 is identified as the area from the Ford Dam to Hastings.
Their most urgent concern is the probable invasion of Asian carp into local waters.
The DNA of the fish was found just north of Pool 2 in .
Once an Asian carp population establishes itself, it will muscle out other fish and gobble up resources, officials say. Silver carp, known to leap out of the water at the sound of boat motors, also pose a hazard to boaters.
Do you spend time on the Mississippi River? You can help The National Parks Service by being a spotter. If you see an Asian carp, photograph the fish and the location and email it to: email@example.com.