Evaluating Effects of Oyster Restoration Reef Design on Habitat Enhancement and Ecology

Oyster reefs provide valuable ecosystem services as Essential Fish Habitat yet are one of the most imperiled marine habitats in the world. Oyster reef restoration is an important tool to rebuild degraded or lost reef habitat and support species of greatest conservation need (SGCN). However, oyster restoration projects can be costly, and resource managers consider a number of design alternatives before selecting the approach with the highest potential return on investment. For example, given a limited amount of cultch material, resource managers must balance how a finite amount of material may be spread across a large area (or what minimum cultch density can be used) and still produce the desired ecological benefits. For example, cultch can be distributed across a smaller site at a larger density (at the cost of restored acreage), or across a larger site at lower density (at the cost of reef complexity). However, because habitat restoration is occurring at a rapid pace, data are often not available to identify restoration actions that will produce the greatest value within financial and operational limitations.

This project will evaluate habitat enhancement provided by low- versus high-cultch density restoration approaches within TPWD’s oyster restoration project on Dollar Reef in Galveston Bay. Monitoring will occur over four years to assess changes in ecological benefits over time. Results from ecological assessments will be coupled with benefit-cost calculations to guide management decisions by identifying restoration treatments (e.g. cultch densities) that provide the highest ecological benefits in support of habitat enhancement goals.