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Freshwater Mollusk Habitats
Often we think of the habitat freshwater mussels live in as just 'water.' This is a very limited view of their world. They actually live in a very dynamic habitat which is closely tied to the habitats that surround it (the stream banks, overhanging trees and surrounding lands). Often this whole area is refered to as the 'riparian zone.'

Riparian zones are very fragile; even minor alterations made by cows or all-terrain vehicles can cause severe damage to the area. These small 'rips and tears' in the fabric of the riparian zone allow runoff of silt and pollutants from the land. Just as high levels of air pollution make it hard for us to breathe the air; clouds of silt in the water choke and smother aquatic animals. Along with the silt, phosphorus, nitrogen, and other nutrients are washed into the river. The fertilizers that help us to grow lush lawns also provide algae in the rivers with nutrients - nutrients at elevated levels that cause them to rapidly reproduce, creating noxious algae blooms. In order to use the nutrients the algae must consume more oxygen, making it even harder for the aquatic animals to breathe.

In areas where the damage to the riparian zone is severe, erosion turns the stream brown; the lack of shade elevates the water's temperature; and both oxygen and food become scarce. The aquatic animals must either move to a more favorable part of the river or face starvation. Every change to the riparian zone causes additional changes downstream. Eventually these changes add up.

There are species of both freshwater snails and bivalves currently on several countries' endangered species lists. Almost all of these mollusks inhabit small, distinct areas that have been severely altered. Most of the listed species are our own freshwater mussels. They are so close but we know so little about them. Follow the links below to see the information we have gathered.

Freshwater mollusks links:

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