Oyster Reef Living Shorelines as a Conservation Practice to Improve Water Quality in Texas Estuaries

Living shorelines are a habitat restoration approach that employs natural elements to protect coastlines while improving water quality, preserving native habitats, and maintaining connections between aquatic and terrestrial areas. Using oyster reefs as living shorelines can help promote favorable water quality because oysters can filter out excess nutrients from the water and their reef structures stabilize the surrounding sediments.As suspension feeders, oysters can reduce suspended sediment and chlorophyll-a concentrations(an indicator of degraded water quality)and enhance fine-grained sediment deposition. Although improvement of water quality through habitat restoration activities has been demonstrated with a high probability of success, using oyster reef living shorelines for the purpose of improving water quality is an innovative conservation approach that is not currently in use in Texas estuaries.

The project will be conducted within the Guadalupe and Mission Aransas Estuaries, both of which support oyster populations and are experiencing shoreline erosion. Within each estuary, sites have been selected both along a salinity gradient, and in high and low wave-energy environments, making an ideal comparison to study the effects of oyster reef living shorelines on water quality improvements. Oyster reef living shorelines will be constructed at eight sites (four per estuary) during the first quarter of the project and will be monitored quarterly for 1.5 years to assess oyster population development, water quality characteristics, and shoreline change. Field data will be used to calculate and compare nitrogen removal capability of oyster reef living shorelines at each site.By demonstrating, evaluating, and verifying the effectiveness of living shoreline practices to provide water quality and shoreline protection benefits, this project will encourage adoption of this innovative conservation approach private landowners, agriculture producers and associated stakeholders.