Oyster Research at ANERR

Researching Oysters for the Economy and for the Environment
Apalachicola Bay is known for delicious oysters, but did you know that these oysters grow more quickly than oysters anywhere else in the United States? It takes Apalachicola oysters about 18 months to grow to legal size, about half the time it takes oysters in Chesapeake Bay to grow to an equivalent size.

Oysters are stationary filter feeders and live their whole lives in one estuary. This means that changes in water quality and the availability of their food supply can affect the health of the oysters. Changes in the health of the oysters can indicate a change in the ecosystem. The health of Apalachicola Bay and the oysters is important to the residents of Franklin County as the oyster industry is a large part of the economy and employs a good portion of the community.

Apalachicola National Estuarine Research Reserve started an oyster-growth monitoring project in spring 2004. Sample sites are located next to the two most commercially-important oyster bars in the Bay: Dry Bar and Cat Point. Each site contains 60 oysters of varying sizes which are measured monthly.

Researchers have discovered that the smallest oysters have the fastest growth rate and their growth rate slows as they grow into the larger-size classes. This suggests that larger oysters could be more vulnerable to decreased nutrients. Of the sites, the oysters at the bar closest to the mouth of the Apalachicola River grow slightly faster than those at the bar further from the river. The river provides the oysters with most of their nutrients and food so these results are expected.

Researchers are now comparing oyster growth rates in drought conditions to those in non-drought conditions, as reduced freshwater flow is a major threat to the Apalachicola Bay ecosystem. During summer 2007, the Apalachicola River experienced the lowest flow levels ever recorded.

This research assists coastal resource managers in assessing ecosystem health and in making management decisions and recommendations in Apalachicola Bay.