The term “living shoreline” refers to a suite of tactics and techniques that aim to stabilize eroding shorelines while providing ecological benefits, such as habitat and water quality enhancement. Shellfish can play an important role in mediating water quality and clarity through their filter-feeding activities. As shellfish filter water, particulate matter and nutrients are removed from the water column and either transferred to the benthos or incorporated into the animals. As such, incorporating shellfish into living shorelines can facilitate ecological outcomes. This study tracked the spatiotemporal population development, and the associated filtration capacity, of oysters and ribbed mussels in three intertidal areas on a living shoreline between 2014 and 2020 across a range of intertidal positions and materials, including recycled oyster shell bags and Oyster Castles ® .
After 6 years, the Mispillion living shoreline successfully developed new ribbed mussel and oyster populations, which filtered nearly 2,500 kg of seston (Fig. 1). Population, and subsequent biomass, development were non-linear for both species across space and time and highlight the tandem synergistic and substitutive benefits of a multi-species approach across intertidal positions (Fig. 2) . Although long-term monitoring across variable materials in multiple intertidal habitats created sampling challenges, the Mispillion living shoreline is a valuable case study for developing a greater understanding of how to maximize the potential contributions of shellfish to water quality goals, and the temporal expectations regarding their development.