This map indicates areas of potentially high and low impact based on our understanding of current levels of human use and their effects on marine habitats. It shows that all areas are likely impacted, however, some more than others.Areas with the highest cumulative impact scores (red) were often found in coastal waters – especially near Boston Harbor, Stellwagen Bank National Marine Sanctuary, north of Gloucester, and through the Great South Channel. Areas of highest cumulative impact generally resulted from the co-occurrence of multiple uses, the high intensity of those uses and stressors, and the relatively high vulnerability of underlying habitats. Land-based impacts diffusing out into coastal waters from the mouths of streams and rivers (e.g., organic and inorganic pollution and nutrients) can be seen as plumes of red, and many coastal pixels have high (orange to red) values because of these and other land-based sources of stress (e.g., light pollution). Demersal habitat-modifying fishing and other forms of fishing, ocean-based pollution and commercial vessel traffic were major sources of impact in offshore habitats. Areas with potentially low impact (relative to other areas) can be found well offshore where multiple human uses are less likely to occur and in areas like Nantucket Shoals due to the restrictions created by natural features (too shallow) and public policy (fishery closures).
Other maps depicting likely impacts are available in the technical report.