Shoreline & Oyster Reef Restoration

MDC Restoration

All materials are biodegradable and last around 2-3 years. This allows time for habitat to restore itself and stabilize, so that by the time our restoration materials degrade, they are no longer necessary for support. The goal is to create a self-sustaining habitat where one has been degraded or been there historically.

Shoreline Stabilization

Major functions: wave break (buffering wave energy as it comes onto to shore) & suitable substrate (an available surface for organisms to settle on or utilize as habitat).

Cement-Jute Volcanoes

Materials: pH balanced cement and jute erosion control material
Construction: damp jute mesh pieces are coated in the cement and then wrapped around a mold to give it its volcano shape
Deployment process: volcanoes are placed in a zig zag formation along a degraded shoreline near low tide. Intertidal vegetation (i.e mangroves, Spartina alterniflora [marsh grass]) is then planted behind.
Goal: accrete sediment overtime (increasing slope), allow planted vegetation to establish themselves, provide substrate for organism to utilize and settle on

Oyster Bags

Materials: biodegradable mesh (BESE company) or basalt rock fiber bags and recycled oyster shell from the Shuck & Share program
Construction: bags are filled with recycled oyster shell (sterilized in the sun for a minimum of 6 months, but typically around 1 year) and tied off on both ends
Deployment process: bags are lined up together, sometimes in two overlapping rows (depending on the state of the shoreline we are working on) and tied together with stainless steel zip ties. Same vegetation as above is planted behind
Goal: accrete sediment overtime (increasing slope), allow planted vegetation to establish themselves, provide substrate for organism to utilize and settle on

POSH (Pervious Oyster Shell Habitat)

Materials: pH balanced cement and recycled oyster shell from the Shuck & Share program
Construction: cement and oyster shell are mixed together in a barrel mixer then dumped into a hexagonal mold. Once set the molds are removed and the units are finished
Deployment process: still in experimentation – in the new parking lot they are spaced in a similar format to volcanoes
Goal: accrete sediment overtime (increasing slope), allow planted vegetation to establish themselves, provide substrate for organism to utilize and settle on

Oyster Reef Restoration

Major functions: provide stable substrate & and recruitment of larval oysters

BESE Oyster Mats

Materials: BESE biodegradable mats (material sourced from the BESE company in the Netherlands – it is made from a potato chip starch byproduct and mold-formed into a sheet that we stack and button together into a two layer mat), stainless steel zip ties, and drilled oyster shells from the recycling program
Construction: 30-36 oyster shells are attached to the mat using stainless steel zip ties
Deployment process: dead shell reefs are raked back down to the correct intertidal level (a level where oysters will be exposed at the low tide and submerged at the high tide) once the dead reef has been restored to the correct elevation BESE mats are placed in a grid pattern with cement hose rings at each corner. The mats are zip tied to the hose rings to keep them submerged, in place, as one large continuous unit. **bags or volcanos are often used on the outer edge of the reef to act as a wave break to protect these materials**
Goal: provide a secure substrate for oysters to settle, and to attract oyster larvae

Frequently Asked Questions

Does MDC use plastic restoration materials?

MDC utilizes a wide range of restoration materials, most of which are natural or biodegradable. These units include our cement and jute volcanoes, Pervious Oyster Shell Habitat (POSH), BESE oyster mats, and native vegetation. Common biodegradable materials used to make these materials include jute, recycled oyster shells, and a pH balanced cement. MDC has utilized plastic restoration materials in past restoration projects and now only utilizes these materials as needed for research.

What happens if restoration efforts don’t work?

When restoration efforts are not working, MDC and partners work to re-evaluate the site to determine next steps. Monitoring of the site is often conducted to determine variables influencing success which can give us answers on how to proceed. Similarly, if older restoration projects become self-sustaining and no longer in need of the original units placed, we work to remove them. When units become damaged, we also work to remove these. Now that majority of our units being used are biodegradable, the need to remove is less of a priority.

Does MDC only work to restore oyster reefs? What other habitats does MDC work to conserve or restore?

A major habitat we work to restore are oyster reefs, but it is not the only one. Restoration efforts are concentrated around oyster reefs, eroded shorelines, and seagrass beds. MDC works with our restoration partners to monitor and restore these habitats. Another conservation focus of ours is around horseshoe crabs and their nesting sites. Learn more here.

What factors are considered in restoration unit design and engineering?

Many factors are considered in restoration unit design and engineering.

Biodegradability: MDC prioritizes the creation and use of biodegradable restoration units, as they best mimic natural environments and minimize our ecological footprint in these habitats.
Durability: Biodegradable materials have significantly shorter lifespans as compared to artificial materials. In an environment like the IRL, materials need to be durable and last minimum of 3-5 years before breaking down to guarantee a positive/successful contribution.
Effectiveness: Success metrics are established for each unit which must be met. Depending on the goal of the restoration project, these metrics could include oyster recruitment, sediment accretion, durability, species diversity, or alternate wildlife impacts.
Community involvement: For MDC specifically, we value community overall. Every restoration unit we make must be inclusive to community participation, so physical demand for creation or the use of caustic materials must all be considered.
Cost: Most of our restoration projects are funded by grants or demand for the units. Biodegradable materials are more expensive to produce and therefore can be an influential factor.

How does MDC minimize its ecological footprint when restoring habitats in the IRL?

MDC takes many steps to minimize our ecological footprint when working to restore habitats. We relocate any remaining live oyster clusters on reefs that are deemed “dead” prior to beginning work. We ensure not to trample or disturb any existing vegetation in areas where we are working. We keep track of all materials and tools being used, and ensure the site is left cleaner than we found it. MDC assists partners in removal of materials that are broken or no longer serving their original purpose. We are also always mindful of the wildlife around us during transport of units, boat transport to/from sites, and while at the restoration site.

How do you determine if a habitat or site needs restoration?

Preliminary monitoring is always used to determine if a site needs restoration. Many databases are also utilized to look at the site’s health and stability in previous years as compared to now. Identifying these sites demands intensive planning, design, permitting, and maintenance. Environmental factors such as slope, erosion rate, wave and energy, and existing vegetations are considered throughout the planning process.

How do you determine if your restoration efforts were successful?

Success metrics are established for each unit, site, and project we work on. Extensive, long-term monitoring occurs for all restoration projects to measure success, and to track habitat health and community interactions overtime. Variables being monitored could include oyster recruitment, sediment accretion, durability, species diversity, vegetated cover, or alternate wildlife impacts.

How does MDC ensure its conservation efforts are sustainable?

Our conservation team works tirelessly to employ science-based methods for restoration and conservation programs. MDC promotes community involvement to ensure long-term stewardship. We also collaborate with local and state partners to align with broader conservation goals.

How can I help?

MDC offers a variety of volunteer opportunities related to the conservation and restoration work that we do. All restoration units are made with the help of volunteers from October through April. We offer a variety of community science opportunities for volunteers to assist in data collection, wildlife monitoring, invasive species removal, and so much more. Learn how to get involved!

Our Mission:

"To protect our coastal ecosystems through education, conservation, and exploration"