The Development, Validation, and Application of the Eelgrass Health Index

• Main Author: Anderson, Nicholas
• Format: Text
• Language: unknown
• Published: University of New Hampshire Scholars' Repository 2020
• Subjects: Cree; Ecology; Eelgrass; Index; James Bay; Video Monitoring; Canada; Chisasibi; Wemindji; Eastmain; Waskaganish; Brant; Subarctic
• Online Access: https://scholars.unh.edu/thesis/1375; https://scholars.unh.edu/cgi/viewcontent.cgi?article=2414&context=thesis

Eelgrass (Zostera marina L) provides essential habitat and forage for waterbirds, fish, and other coastal marine species, nutrient and sediment capture which improves water quality, carbon storage, and wave energy buffering which reduces coastal erosion. Changes in its health can indicate other coastal ecosystem changes. Since the 1980s, eelgrass beds have declined in James Bay, Québec. The eelgrass decline coincided with a decrease in the abundance of migratory Brant and Canada geese visiting the coastal eelgrass meadows, which the geese rely on for forage during their spring and fall migrations. Geese are important species to the coastal First Nation Cree communities of Québec and are harvested by the Cree during these migration periods. The decline in eelgrass and geese threatens culturally significant hunting activities of the First Nation Cree communities of Chisasibi, Wemindji, Eastmain, and Waskaganish. Multiple hypotheses exist for the eelgrass decline but no causes have been directly linked to the loss of eelgrass. As part of a larger coastal habitat monitoring program in James Bay focused on investigating the decline of eelgrass and potential threats and stressors, we developed novel eelgrass monitoring methods suited to the large spatial area and subarctic conditions as well as the eelgrass health index, an index for assessing eelgrass health status. This study assessed video monitoring as a potential methodology for monitoring eelgrass. Video monitoring and conventional observations were conducted side by side in the Great Bay Estuary in Maine and New Hampshire and compared. Observations for three eelgrass parameters, percent cover, shoot density, and plant height, were made during July and August 2019. Validation for each eelgrass parameter using conventional methods demonstrated that video monitoring results were consistent with results from conventional monitoring. Each of the parameters observed using both methods demonstrated a significant positive linear relationship (p < 0.0001) with a ...