Good question...bivalves are filter feeders and in areas with zebra mussel infestations the water clarity is off the charts - not necessarily a good thing as that water is likely devoid of any nutrients, also. I'm far from a bivalve expert...I do enjoy a green lip mussel sauteed in garlic butter from time to time, however.

Many men go fishing all of their lives without knowing that it is not fish they are after. ~ Henry David Thoreau

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