Priority Habitat is based on the known geographical extent of habitat for all state-listed rare species, both plants and animals, and is codified under the Massachusetts Endangered Species Act (MESA). Habitat alteration within Priority Habitats may result in a take of a state-listed species, and is subject to regulatory review by the Natural Heritage & Endangered Species Program. Estimated Habitats are a sub-set of the Priority Habitats, and are based on the geographical extent of habitat of state-listed rare wetlands wildlife and is codified under the Wetlands Protection Act (WPA), which does not protect plants. State-listed wetland wildlife species are protected under the Massachusetts Endangered Species Act as well as the Wetlands Protection Act.
Priority and Estimated Habitat maps are used for determining whether or not a proposed project must be reviewed by the NHESP for MESA and WPA compliance and can be found in the Massachusetts Natural Heritage Atlas. Access to Priority and Estimated Habitat maps is provided through a variety of sources:
- The Atlas is available for use through most town libraries
- The Atlas can be purchased from NHESP in book or CD format
- A large-scale map has been provided to each Conservation Commission, Planning Board, and Building Inspector showing the entire town
- An interactive map viewer with address-matching capability is available online
- Priority Habitat GIS datalayers and Estimated Habitat GIS datalayers can be downloaded from MassGIS (appropriate software required for use).
It is the responsibility of the land owner or project proponent to determine if their project falls within Priority Habitat or Estimated Habitat and requires review. Failure to file under MESA constitutes a violation of the Act and is subject to a fine .
Site specific rare species information for regulatory review can be requested from the NHESP by submitting a MESA Information Request Form . This is not required as part of a MESA Project Review, however, it is highly recommended that project proponents request this information prior to development of site plans, especially if the project falls within Priority Habitat or Estimated Habitat for rare species.
For large projects, we suggest that proponents contact the NHESP early in the planning stage to discuss potential MESA issues.
If you are requesting information for habitat management or conservation purposes and you are a non-profit conservation group, government agency or working with a government agency fill out a Data Release Form . Do not fill out a MESA Information Request Form.