Pacific oysters are a sink and a potential source of the eelgrass pathogen, Labyrinthula zosterae

Oyster aquaculture and seagrasses often co-occur are each vital to the ecological economic value of coastal ecosystems. Global declines in seagrasses, including Zostera marina , have recently been observed association with multiple factors, infection diseases such as seagrass wasting disease (SWD), caused by protist Labyrinthula zosterae . Protection has led restrictions on oyster due perceived negative impacts beds; however, positive may also occur. An important species, Pacific Crassostrea gigas can filter L. from water, potentially reducing pathogen transmission, although oysters vector if they accumulate release live into water. We investigated whether presence decreases lesion severity intensity eelgrass, or acts a via laboratory field experiments. In laboratory, eelgrass were exposed for 24 h kept at 11°C 18°C 13 d. field, ramets deployed without 28 d adjacent known SWD. experiment, significantly decreased intensity, but previously did transmit naïve eelgrass. Temperature not affect ability mitigate SWD; increased temperature severity. Oysters had no effect SWD field. Further research is needed regarding potential quantify when reduce