Plastic Free Oyster Reef Restoration Project at Rookery Bay

On February 22nd, twenty-two plastic free prisms were readied for deployment and volunteers gathered for the historic launch. The morning consisted of physically moving the prisms to its deployment site on Shell Island Road. According to Mike Sipos, “the project is permitted, the materials are ready 

and the low tide and weather are perfect for deployment.”

A group of volunteers created these Plastic Free Oyster Shorelines Prism structures on April, 2022, during a hands-on workshop. This is a new project aimed at reducing plastic use in oyster restoration and is called “Partnership for Plastic-Free Restoration of Oyster Shorelines,” or PROS for short. 

The workshop was led by Michael Sipos, a University of Florida Sea Grant Extension Agent, who manages the Collier County Sea Grant Extension Program, which is a partnership between the University of Florida's Institute of Food and Agricultural Sciences (UF/IFAS), and Florida Sea Grant and Collier County.

The project is to “promote the restoration of an eroding shoreline with native wetland vegetative enhancement plantings and the placement of a series of oyster prisms in four locations along Monument Trail at the end of Shell Island Road.”

According to the permit, “this project is to mitigate the evident erosion along the north, northeast length of the trail and to provide structures for oysters and other filter feeding invertebrates to recruit to.”

The Reef prisms are made from a combination of jute-fiber erosion control mats and a rapid setting, low-shrink grout available from local big box stores. The chemical formulation of this grout allows for roughly seven times higher break strength, a 35 to 50% lower carbon footprint, a more neutral pH (8.5 vs. 12.1), and significantly faster setting time in comparison to Portland cement. 

The development team at the University of Florida, led by Dr. Mark Clark, spearheaded the creation of reef prisms. They wanted a modular, plastic-free alternative to shell bags that staff could also build and deploy with volunteers using affordable and readily available materials.

As interest in reef prisms mounted, UF/IFAS Extension and Florida Sea Grant brought organizations across Florida together to form the PROS Community of Practice through a grant from the Department of Environmental Protection.

According to Dr. Mark Clark of the University of Florida, the network of partners involved are very excited in using a newly developed plastic-free material called reef prism. This network consists of practitioners, educators, and local government partners who are working toward to implementing living shoreline projects using the newly developed plastic-free material called reef prisms.

Living shorelines (coastal erosion control using native vegetation and other natural elements) are increasing in popularity as practitioners and homeowners learn about their many benefits. However, one of the most common living shoreline approaches – creating reefs by stacking up rows of “shell bags” (oyster shells contained in plastic nylon mesh sacks) – is highly problematic for shoreline restoration applications. This is due to the likelihood that the plastic mesh releases harmful microplastics into the marine environment and the concern that wildlife could become entrapped or entangled, especially as bags break down or if the reef project fails to establish.

The prisms were installed within the intertidal zone inside 10-feet from the mean high water line and deployed at low tide and should be mostly covered with water during high tide. No heavy equipment or tools were used during the process.

The shoreline is primarily covered with red mangroves and the project also required shoreline plantings of sprouted red mangrove propagules to accompany the installation of the prism structures at each site.

This restoration project is part of a larger FDEP funded initiative titled Partnership for PROS with five regions identified throughout Florida that have conducted or are planning similar restoration projects using the same prism structures.

The reef prism process and material are fully open-source and available for any organization to adopt and apply for free through joining the PROS Community of Practice.