Stressor Influence on Eelgrass (Zostera marina L.) Distribution

In the Pacific Northwest, the dominant seagrass, Zostera marina occurs primarily in the intertidal portion of bays and estuaries and in many areas overlaps with commercial aquaculture.  With continued climate change, both seagrass and aquaculture species are subjected to stressors such as increased temperature, acidification, and disease in addition to other stressors.  In this presentation I highlight several cases of eelgrass collapse in California & Oregon as well highlighting local changes in both native and non-native seagrass in Yaquina estuary.  Further, I present a working hypothesis for the collapse of these populations.  Ongoing research is directed at better understanding the stressors responsible for eelgrass loss in Oregon estuaries. 

Impact/Purpose

Seagrasses are frequently considered a sentinel species of estuarine health and productivity since they are sensitive to nutrient enrichment, temperature and water clarity and are long-term integrators of environmental conditions.  Estuaries are increasingly subjected to stress from natural and anthropogenic nutrients as well as changing temperatures and coastal acidification. This lightning presentation will focus on local and regional changes in the presence and distribution of native eelgrass (Zostera japonica L). and non-native Japanese eelgrass (Z. japonica Aschers. & Greabn) in relation to changing stressors. The presentation draws heavily on more than 20 years of research conducted at ORD’s Pacific Coastal Ecology Branch (CPHEA/PESD) in Newport, OR.  

Citation

Kaldy, J. Stressor Influence on Eelgrass (Zostera marina L.) Distribution. Hatfield Marine Science Center, Community Workshop: Developing community guidelines for sustainable co-management of SAV and shellfish in OR, Newport, OR, January 24, 2024.