Significant development in Southern California coastal areas has altered marine habitat that would normally buffer wave energy, leaving shorelines vulnerable to erosion. Living Shorelines projects seek to address this problem by restoring native habitat with the goal of rebuilding ecosystems in a way that provides ecosystem services such as shoreline stabilization. Foundation species such as oysters and eelgrass are increasingly used in these projects because they provision habitat and reduce erosion. Native Olympia oyster beds and eelgrass beds were restored at four sites in Upper Newport Bay in 2016 as part of the Upper Newport Bay Living Shorelines Project to explore the possible combined benefits of restoring two foundation species. All sites have seen differential success since initial restoration in terms of oyster density and bed growth . Human activity such as trampling and wave energy has been previously linked to mussel and oyster bed degradation, so to understand the impacts of human activity on restored oyster beds 30-minute human use surveys were conducted at all sites and all instances of human activity including recreation, fisher activity, boating, and the size of wakes produced by each passing boat were documented. Water level loggers were also deployed to directly measure boat wake energy with and without Living Shorelines plots.
Preliminary analyses show evidence of reduced wave energy by Living Shorelines plots and a trend towards reduced oyster density with increased frequency of large boat wakes . Early evidence also shows that the negative impacts of boat wake energy on oyster density are reduced when oysters are restored upshore of restored eelgrass. This suggests that eelgrass may protect oyster beds from damaging wave energy created by passing boats . Teasing out the ecosystem services provided by these restored habitats can help design future restorations as well as inform our understanding of the ecology of L iving S horeline species.