The zebra mussel is a native species of the Europe area. It was originally introduced into the United States by accident, through the ballast water in ocean-going freighters that came from European ports" (Officials). The reason this was possible was because the ballast tanks equalize the weight of the ship and its cargo by filling up with the same water from which the ship floats, and also taking what ever may be in the water into the tanks as well. Then later they empty the water at a different location, relocating what ever was in the tanks to a new ecosystem, where the problems soon followed.
             Once they were introduced into the lake they began to reproduce at an alarming rate. The problem was at first, just as with most other alien species there were not any known predators in order to keep the numbers at bay. Soon after other problems began to develop. The mussels liked to be around flowing water, because that would bring food to them. This posed a big problem for those who relied on intake pipes such as power plants. The mussels would crowd around these intake pipes so tightly that they would in some cases actually stop the flow of water through these pipes. Also the zebra mussel "devours microscopic plants at the bottom of the food chain" (Faber B1). These plants are vital to the survival of the native species of the lake. If a part of the food chain is broken especially close to the bottom then the entire ecosystem suffers. In some cases the introduction of this species to lake Erie was thought to be "worse than the oil spill in Alaska" (Faber B1). Reason being, exotic introductions are permanent and spreading, they can't be cleaned up like oil spills. In a hundred years it is possible to substantially clean up an oil spill, but for the zebra mussels they will have spread across America. It was only at first that this mussel was thought to be all bad, but after a couple years of
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