We considered four primary project types for the GEMS project: habitat restoration, restoring hydrological connectivity, recreational enhancements, and water quality infrastructure improvements. These projects vary greatly in the process and materials used, environmental conditions required, social and legal contexts, and expected outcomes (economic, health, recreation, harvest, shoreline protection, recreation etc.). Summaries of the project types included in the GEMS project are provided below. To see more detail about each project type, including key outcomes and ecosystem service logic models, click the names of individual project types below or search the ESLM database.
Project Types
ESLM Project Types
Project Type: Oyster Reef Restoration
General Oyster Reef Restoration
Project type: Oyster Reef Restoration
Structurally Simple, Subtidal, Intensively Harvested Oyster Reef Restoration
Project type: Oyster Reef Restoration
This technique consists of placing cultch material (usually oyster shells, relic shells, crushed limestone, or crushed concrete), either loose or contained, so that the resulting structure lies flat along the estuary/ocean floor. This technique has been widely used throughout the Gulf for the primary purpose of providing oysters for harvest.
Structurally Complex, Subtidal, Intensively Harvested Oyster Reef Restoration
Project type: Oyster Reef Restoration
Large, durable structures (e.g. oyster balls, precast concrete structures, and limestone structures) are placed in subtidal areas to create substrate to which oysters can attach. The resulting oyster reef has a significant vertical component, provides a more complex structure which oysters (of varying ages) and other aquatic organisms can use for habitat, and is less likely to be buried by sediment or degraded by waves than the simpler structures in the previous technique.
Structurally Complex, Subtidal, Not Intensively Harvested Oyster Reef Restoration
Project type: Oyster Reef Restoration
This technique is identical to Structurally Complex, Subtidal, Intensively Harvested Oyster Reef Restoration, except that intensive harvesting (dredging or intensive tonging) is not permitted.
Structurally Complex, Intertidal, Not Intensively Harvested Oyster Reef Restoration
Project type: Oyster Reef Restoration
Large, durable structures (e.g. oyster balls, precast concrete structures, rocks, limestone structures) are placed in intertidal areas to create substrate to which oysters can attach. Projects using this technique are often called “living shoreline” projects, as they are intended to protect shorelines from erosion by stabilizing sediment and attenuating waves as they approach the shoreline.
Protection or Enhancement of Existing Oyster Reef
Project type: Oyster Reef Restoration
These projects focus on the protection of an existing oyster reef from intensive harvest (dredging), with or without reef enhancement (via seeding or placing oysters in existing reef area). Protected reefs could still allow low-impact harvesting methods (tonging or hand collection) that do not threaten the reef structure or long-term viability of the oyster populations. The objective of these projects is to support a sustainable oyster population, allow the reef to develop structurally over a long period, and possibly to create a source of oyster larvae to nearby reefs.
Oyster Aquaculture
Project type: Oyster Reef Restoration
Oyster aquaculture projects of varying methods, including all bottom and off-bottom techniques. These projects encompass both intertidal and subtidal projects, and are considered to be intensively harvested, since the primary goal of oyster farming is harvest and consumption.