“A single Seaway ship can hold up to six million gallons of vessel-steadying ballast water that gets discharged at a port in exchange for cargo. And that water, scientists would learn after it was too late, can be teeming with millions, if not billions, of living organisms.” EcologyGreat LakesInvasive SpeciesLake MichiganQuagga Musselsa MusselsSt Lawrence Seaway Book:The Death and Life of the Great Lakes Source: The Death and Life of the Great Lakes