Sentinel Monitoring of Salt Marshes in the Wells National Estuarine Research Reserve

Created: 3/30/2010 - Updated: 3/02/2020


The Wells Reserve, along with four other National Estuarine Research Reserves, is acting as a sentinel site to monitor climate change impacts on salt marsh habitat. This project involves creating a long-term ecological monitoring program to determine the effects of sea level rise, saltwater intrusion, warmer temperatures, and coastal storms on salt marshes.


The Wells Reserve in southern Maine protects over 2,000 acres of coastal habitats, including salt marshes, wetlands, dunes, and forests. The Wells Reserve is part of a national effort, created in 2007, to establish salt marshes as long-term reference sites at five reserves (Narragansett; Wells, Maine; Chesapeake Bay, Virginia; North Carolina; South Slough, Oregon). In addition, the reserve, along with other NERRs, participates in the System Wide Monitoring Program (SWMP), tracking changes in water quality, plants, animals, and habitats within the reserve over time. Salt marshes provide valuable habitat for fish, crabs, and other wildlife, and important ecosystem services by filtering water and protecting shorelines during strong coastal storms. Salt marshes in the reserve area have been altered by humans through dams, dredging, ditches, culverts, tide gates, filling, and development; these activities have resulted in restricted flow, reducing access for marine wildlife and causing continual habitat degradation. This habitat is also threatened by climate change; impacts of concern include sea level rise, warmer temperatures, and coastal storms.


This project is funded through the National Oceanic and Atmospheric Association and has two goals: 1) use natural marshes as references to understand what is happening at restored marshes, and 2) use these natural reference sites to understand how marshes across the United States are responding to the impacts of climate change. The reserve is monitoring salt marsh characteristics (e.g., salinity, vegetation cover, flow patterns, peat soils) at natural marsh reference sites and recently restored marsh sites every year to track water levels and marsh height. This project will determine if and how salt marshes can respond to sea level rise and other climate impacts. In addition, the Wells Reserve monitors for indicators of salt marsh health such as population densities of birds and larval, juvenile, and adult utilization.

Outcomes and Conclusions

This project will provide a long-term data set on salt marsh response to climate change impacts and inform a broader national effort. This information can be used in other restoration efforts.


Information gathered from online resources. Last updated on 3/30/10.


Gregg, R. M. (2010). Sentinel Monitoring of Salt Marshes in the Wells National Estuarine Research Reserve [Case study on a project of the Wells National Estuarine Research Reserve]. Product of EcoAdapt's State of Adaptation Program. Retrieved from CAKE:… (Last updated March 2010)

Project Contact(s)

The Wells Reserve is one of 27 reserves in the National Estuarine Research Reserve System (NERRS). Currently, NERRS protects over one million acres of estuarine waters and adjacent upland habitats. The Wells Reserve focuses on research, education, and stewardship, and operates programs in coastal research and monitoring, environmental learning and decision-maker training, and land and water resource management.

NOAA is an agency that enriches life through science. Our reach goes from the surface of the sun to the depths of the ocean floor as we work to keep citizens informed of the changing environment around them. From daily weather forecasts, severe storm warnings and climate monitoring to fisheries management, coastal restoration and supporting marine commerce, NOAA’s products and services support economic vitality and affect more than one-third of America’s gross domestic product.


Scale of Project
Community / Local
Sector Addressed
Conservation / Restoration
Target Climate Changes and Impacts
Air temperature
Salinization / Saltwater intrusion
Sea level rise
Storms or extreme weather events
Water temperature
Climate Type
Type of Adaptation Action/Strategy
Natural Resource Management / Conservation
Initiate targeted research program
Monitor climate change impacts and adaptation efficacy
Taxonomic Focus
Other Invertebrates
Effort Stage
In progress