Habitat Restoration

Shellfish Reefs

The Gulf Coast Marine Life Center’s Shellfish hatchery and nursery will be capable of producing oysters at different life stages for reef building, living shorelines and enhancement of existing reefs.

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Oyster Reef

Oyster reefs are considered extremely valuable habitat in estuarine and near-shore ecosystems. Throughout their natural range, oysters are generally the only hard substrate in an otherwise soft sediment environment. The three dimensional structure of oyster aggregations provides ideal habitat for colonization by dense communities of invertebrates, including other molluscs, crustaceans, and polychaetes which then attract foraging fish and larger invertebrates such as crabs and shrimp. It is estimated that 80 – 90% of fish captured in recreational saltwater fisheries and 75% of the nation’s commercial fish and shellfish depend on estuaries during some portion of their life cycle. The habitat importance of oyster aggregations in temperate regions has been compared to that of coral reefs in shallow tropical and subtropical environments. However, these vital habitats are being lost at a staggering rate throughout the world and particularly in the GOM. The Gulf Coast Marine Life Center’s restoration efforts are needed to help reverse these negative trends.

Furthermore, studies have established that oyster beds biologically remove at least 20% of the nitrogen in wastes through a process similar to what is used in modern wastewater treatment plants. While most of the nutrients filtered from the water by shellfish are recycled back into the water column, the flux of undigested plant matter into the sediments stimulates bacterial processes known as denitrification. This process of turning fertilizer ammonia into nitrate and then into harmless nitrogen gas allows its escape into the atmosphere, instead of stimulating phytoplankton blooms that shade seagrass and limit their growth.

These findings suggest that if large shellfish populations could be restored through commercial farming, stock enhancement or habitat restoration, these beds could play an important role in helping to achieve nitrogen reductions to mitigate the effect excess nitrogen has in our bays and estuaries. Through the incorporation of such efforts the Gulf Coast marine environment will benefit from the habitat to support marine life and biological diversity, as well as cleaner water to assure a healthy environment for the plants, animals, and people who rely on a healthy Gulf of Mexico ecosystem.

The Center will further benefit the environment as a whole by expanding on research conducted on wild shellfish. Utilizing the Center's resources, wild shellfish can be analyzed and relied upon as early indicators of environmental problems. As filter feeders and biomass accumulators, shellfish are an excellent bioindicator and present unique opportunities to get a better understanding of the offshore environment.

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Oyster Reef

Already, a number of artificial offshore reefs that could benefit from shellfish enhancement in local bays and throughout the Gulf of Mexico have been identified. As with all aspects of interaction with the natural environment, all efforts to supplement existing artificial and natural reefs with shellfish will be conducted with consultation from local scientists and experts in order to ensure maximum sustainability and benefits to the local Gulf of Mexico ecology for many years to come.