What happens to water quality when you remove an oyster farm from a bay? Oysters strain microscopic algae out of the gallons of water they filter every day. A single oyster can filter as much as 50 gallons a day. A unique opportunity to answer this question emerged when about 5 million cultured Pacific oysters were removed from Drakes Estero in California.
Now that the oysters were gone, would there be more algae? Might different species become more abundant, perhaps ones that might be harmful or toxic species? How did the presence of oysters affect nitrogen availability? These questions are important to answer so we understand how oyster farming and restoration of oyster reefs might affect water quality and what the historic ecological role of oysters might have once been in estuaries and bays.