Jackson Estuarine Laboratory

Seaweed Monitoring in the Great Bay Estuary: 2019 Annual Report

Creative Commons License

Creative Commons Attribution 4.0 International License
This work is licensed under a Creative Commons Attribution 4.0 International License.


As global warming increases temperature and nitrogen inputs change—either due to greater inputs associated with growing populations in the Great Bay or with nitrogen reductions at wastewater treatment plants—it is important to understand how these changes are impacting the estuary. To that end, the abundance and taxa of intertidal seaweeds have been assessed at fixed locations throughout the estuary since 2013. Seaweed abundance may be influenced by environmental conditions such as nutrient levels, water temperature, light availability, and invasive species. Therefore, seaweed communities can provide insights into the overall health of the estuary and signal ecological change. In 2019, abundance data (percent cover and biomass) were collected from five of the eight intertidal sampling locations and four subtidal locations. Data from 2013-2019 show appreciable cover and biomass of nuisance seaweeds (reds and greens), including several introduced species. Green seaweeds decreased in cover at the two intertidal sites that are sampled annually (Depot Road and Adams Point), and cover of red seaweed decreased at one site (Depot Road).


Jackson Estuarine Laboratory

Publication Date


Grant/Award Number and Agency

NOAA's Office for Coastal Management (CZM) under the NH Department of Environmental Services Coastal Program and through the Piscataqua Region Estuaries Project and The Davis Foundation

Scientific Contribution Number

Jackson Estuarine Laboratory Contribution Series #576

Document Type