Zebra Mussel's Environmental Impact On The Colorado River

At first glance of a Zebra Mussel (Dreissena Polymorpha), the description “invasive species” might not come to mind. Zebra mussels look like harmless shellfish, but they can actually cause more harm than good because they are not indigenous to the United States. In particular, the niche filled by zebra mussels has an environmental impact on the Colorado River.
Zebra mussels upset the balance of marine biology. Zebra mussel fertilization occurs in water columns—the area from surface to sediment of a sea, river or lake—because the temperatures of these water columns are ideal environments for reproduction. The problem is that zebra mussels lay over 40,000 eggs in one reproductive cycle “and up to one million in a spawning season” (Benson et al. par. 4). At the rate that they reproduce, zebra mussels can easily outnumber and destroy floral and fauna of marine life where they spawn.

The diet of a zebra mussel includes algae, zooplankters, bacteria and detritus (Woodward and Quinn 85). Zebra mussels have a filtering capacity to change the ecosystem of rivers and lakes by eliminating phytoplankton. Some freshwater fish depend and feed on zooplankters, and by eliminating phytoplankton, zebra mussels reduce the number of zooplankters and thus, reduce the number of naturally occurring fish that feed on zooplankters, as a result (Woodward and Quinn 85). As the number of indigenous fish decreases, the result is an increase of other fish not native to the ecosystem; however, they help create an ideal environment for the zebra mussel to thrive in, which results in an over population of zebra mussels. With this kind of environmental impact on an ecosystem, zebra mussels then, catch a ride on ships and boats to the next waterway, and start the process all over