AUGUSTA — The Maine Natural Areas Program within the Department of Agriculture, Conservation and Forestry has introduced an updated marsh migration model and a comprehensive report.
This initiative aims to help communities and land managers identify critical areas necessary for the inland migration of tidal marshes anticipated under projected sea level rise scenarios.
Maine’s approximately 22,000 tidal marsh acres provide diverse ecosystem services such as carbon sequestration, water quality enhancement, recreational opportunities, and habitat for various plant and animal species. Additionally, they serve as natural buffers to coastal communities, mitigating flooding and reducing the impact of storm surges and waves. But these vital ecosystems face threats from sea level rise, coastal development, and other human-induced disturbances. As sea levels continue to rise, existing tidal marshes may respond by either “keeping up” through sediment deposition or migrating inland, depending on geomorphic conditions and land-use factors.
MNAP’s updated tool presents current tidal marsh areas along the Maine coast alongside projected migration spaces, enabling planners, local leaders, and conservation organizations to visualize and plan for marsh migration under various sea level rise scenarios, ranging from 1.2 to 10.9 feet.
An analysis of potential marsh extent indicates that Maine is likely to experience a net loss of tidal marsh habitat over time, as some current marshes may become inundated, and available migration space is limited. Only approximately 31% of potential marsh migration space across all sea level rise scenarios is conserved statewide, underscoring the need for additional conservation efforts for current and future marsh areas.
For more information, email Lisa St. Hilaire, Maine Natural Areas Program information manager, at [email protected].