How do Oyster Reefs Protect Shorelines with Claire Arre

Audio by: Wangyuxuan Xu | Writing by: Marie Hogan, Amanda Neslund, Alexandra Jade Garcia  | Socials by: Sofia Del Priore

Oysters can serve as an important environmental solution to shoreline restoration. Oysters reefs can provide habitat for hundreds of marine species, improve water quality, as an adult can filter up to fifty gallons of water a day, and the reefs protect against erosion and storm surges. Oysters also help stabilize sediments and wave energy, which helps to reduce coastal erosion and the impacts of sea-level rise. As filter feeders, oysters help remove excess nutrients from the water and maintain healthy water quality. This ecosystem service is especially important with urban and agricultural run-off entering waterways, as oysters filter excess nitrogen, which can help prevent harmful algal blooms. Oyster restoration is important for conservation as well, as within the past two hundred years nearly 85% of global oyster reefs have been lost from overharvesting, wetland loss, human development, pollution, and other anthropogenic factors. Oyster reefs also serve as natural flood control and sea-level rise solutions, and compared to man-made solutions like seawalls and levees, oyster reefs are more cost-effective and less disruptive to the environment. 

In Newport Beach, California, the clean water organization Orange County Coastkeeper has re-introduced oyster reefs as part of their shoreline restoration program. The goal of the organization was to address habitat loss, sea-level rise, improve water quality, return the native depleted Olympia Oyster, and enhance the habitat quality for fish and wildlife. In 2017, the organization created an oyster habitat to re-integrate the Olympia oyster into the Upper Newport Bay. The Coastkeeper and volunteers hand-sewed over 500 bags, using coconut coir, to transport 40,000 pounds of Pacific oyster shells to create a habitat where Olympia Oyster could settle. Since the initial restoration, the CostalKeepers have been monitoring the restored oyster beds yearly and have reported signs of healthier and more sustainable coastline. 

The Orange County Coastkeeper has also worked to restore Eelgrass in the Upper Newport Bay. Eelgrass is a shallow coastal seagrass and foundational species, as it provides habitat and food for many juvenile fish, lobsters, and shellfish. Eelgrass has been targeted for restoration as it has many critical ecosystem services from oxygen production, nutrient cycling, and providing “carbon service”  as it absorbs carbon which helps fight ocean acidification. In 2012, Orange County Coastkeeper worked in collaboration with the Department of Fish and Wildlife staff at the Back Bay Science Center to plant 0.3 acres of eelgrass. The goals of their restoration were to increase the diversity or abundance of native species, establish a sustainable eelgrass habitat and restore the economic value of the recreational and commercial fishery in the Bay. The Coastkeeper’s efforts have been successful as Upper Newport Bay now has over one acre of eelgrass habitat. 

The Orange County Coastkeeper is a non-profit with a mission to protect the region’s water for present and future generations. The Coastkeepers act as stewards to protect both fresh and saltwater ecosystems, while working to build regional, comparative approaches to watershed management in both the private and public sectors. The goals of the organization are to meet the needs of both the environment and their community, conduct water quality research to provide evidence for environmental actions and policy, ensure compliance with environmental laws, raise awareness about environmental issues, implement local actions and programs, and provide community education. 
Claire Arre is the Orange County Coastkeeper’s Marine Restoration Director. In her role, she manages the shoreline restoration program and works to restore the health of Orange County waters. Arre graduated from California State University, Long Beach with a Bachelor of Science in Marine Biology and received her Master of Science degree in BIology from California State Polytechnic University, Pomona. In her free time, Claire volunteers at Cabrillo Marine Aquarium as a Whale Watch naturalist. 



Claire: Looking forward to what the climate is going to do to our coastal ecosystems our problems are going to build on top of each other. So we need to find better solutions.

Ethan: I’m Ethan Elkind, and this is Climate Break. One of those solutions? Using oysters and other native species as an alternative to man-made methods of dealing with climate change-induced storm surges and erosion, according to Claire Arre [AR-EE], Marine Restoration Director at Orange County Coastkeepers.

Claire: We call it a living shoreline project. So it makes our shorelines more resilient to things like erosion as well as sea level rise.

There’s lots of different organisms that would do really well within a living shorelines approach. It would just depend on your particular area.

Oysters have the ability to create oyster beds, which are actually a pretty hard structure. You can imagine oyster shell is a place to deposit calcium and as they grow and build, they actually attach to each other and kind of create this natural formation. And it has quite a few. Positive impacts on the ecosystem. Oysters filter water. everything from sediments to pollution, extra nutrients. Help water quality. Um, and they really are kind of a natural wall barrier.

They maintain themselves unlike things like rip rack or bulkheads, , that humans really have to protect and they don’t really create a lot of habitat. Oysters have the ability really create a living space

Ethan: To learn more about how Orange County Coastkeeper is using native oysters and eelgrass to bolster shorelines from the impacts of climate change and to get involved with similar projects in your area, visit

How do Oyster Reefs Protect Shorelines with Claire Arre