Land Use as of 2005
There are 351 towns/cities in Massachusetts.
| Acres of developed land: | 3,474 |
| Acres of natural land: | 1,926 |
| Acres of agricultural land: | 31 |
| Acres of open land, recreational land, golf | 965 |
| Acres of open water: | 315 |
| Acres of other: | 28 |
| Percent developed: | 51.5% (36) |
| Percent natural land: | 28.6% (323) |
| Percent in agriculture: | 0.5% (306) |
| Total acres: | 6,738 (300) |
| Total square miles: | 11 (300) |
Recent Development
There are 351 towns/cities in Massachusetts.
| Natural land (acres) converted to development (1999-2005): | 31 (313) |
| Total area of newly developed land from 1999 to 2005, standardized by geographic area size (acres per square mile) | 3 (280) |
| Percent of homes built between 1999 and 2005: | 5.4% (194) |
| Average living area of new homes between 1999 and 2005: | 4,614 (8) |
| Population in 2000: | 27,066 (64) |
| Estimated population in 2007: | 26,985 (65) |
| Total acres: | 6,738 (300) |
| Total square miles: | 11 (300) |
Protected Land
There are 351 towns/cities in Massachusetts.
| Overall protected acres: | 949 (280) |
| Overall percent protected: | 14.1% (223) |
| Acres protected (1999-2005) | 16 (226) |
| Percent of BioMap Core acres protected: | 0.1% (299) |
| Percent of Supporting Natural Landscape protected: | 9.2% (219) |
| Percent of Living Waters Core protected: | 0.0% |
| Percent of unprotected Living Waters CSW that are developed: | 18.0% (115) |
| Percent of natural land protected: | 28.6% (153) |
| Percent of agricultural land protected: | 51.9% (15) |
| Total acres: | 6,738 (300) |
| Total square miles: | 11 (300) |
The BioMap Core Habitat layer depicts the most viable habitat for rare species and natural communities in Massachusetts. It was produced in 2001 by the Natural Heritage and Endangered Species Program (NHESP). In addition to the Cores, the BioMap Supporting Natural Landscape buffers and connects the Core Habitat polygons and identifies large, naturally vegetated blocks that are relatively free from the impact of roads and other development.
The Living Waters project completed by NHESP in 2003 depicts those areas important for conservation of aquatic resources. The Living Waters Core Habitats represent lakes, ponds, rivers, and streams that are important for the protection of freshwater biodiversity in Massachusetts. The Living Waters Critical Supporting Watersheds (CSWs) are those areas with more immediate hydrologic contributions to Living Waters Core Habitats. As such, they represent the areas with the highest potential to sustain or degrade Core Habitats.
We included the following land use types as "Natural": forested, forested wetlands nonforested wetlands, salt wetlands, powerlines, saltwater sandy beach, and brushland/successional. While powerlines are built by humans and continue to be managed, they are also host to species found only in early successional habitats. For this reason, they were included natural.
We included the following land use types as "Agricultural": cropland, pasture, cranberry bogs, orchard, and nursery.
The NHESP Natural Communities datalayer consists of polygons that represent the extent of various natural communities of biodiversity conservation interest in Massachusetts. These polygons are based on records of natural communities maintained in the NHESP database.
The Priority Habitats of Rare Species datalayer contains polygons representing the geographic extent of Habitat of state-listed rare species in Massachusetts based on observations documented within the last 25 years in the database of the Natural Heritage & Endangered Species Program (NHESP).
Ecological Impacts
There are 351 towns/cities in Massachusetts.
| Index of ecological integrity in 1971: | 0.02 (336) |
| Index of ecological integrity in 2005: | 0.01 (335) |
| Percent loss in ecological integrity (1971 - 2005): | 25.1% (209) |
| IEI Acres in 1971: | 104 |
| IEI Acres in 2005: | 78 |
| Acres of natural blocks with an IEI value > 0.5 and greater than 50 acres in size (1971): | 0 |
| Acres of natural blocks with an IEI value > 0.5 and greater than 50 acres in size (2005): | 0 |
| Total square miles: | 11 (300) |
Measuring the Ecological Impacts of Development
We estimated the ecological impacts of development by running a model designed to assess the ecological integrity of lands and waters across relatively large geographic extents (e.g., all of Massachusetts). Ecological integrity can be thought of as the ability of an area to support plants and animals and the natural processes necessary to sustain them over the long term. The model is called the Conservation and Assessment Prioritization System or CAPS and it presumes that by conserving intact areas of high ecological integrity, we can conserve most (but not necessarily all) species and ecological processes.The "index of ecological integrity" (IEI) was calculated for all areas of the state in 1971, 1985, 1999, and 2005. It takes into account eight factors when generating results: habitat loss; microclimate alterations; impacts from domestic predators such as cats and dogs; impacts from edge predators such as raccoons, blue jays, and cowbirds; non-native invasive plants; non-native invasive earthworms; connectedness of the landscape; and similarity of each point to the surrounding landscape. The result is that each cell (30 x 30 meters) in the state is given a score between zero and one, zero being a low score while one is the highest score possible.
IEI-Acres Defined
The Index of Ecological Integrity (IEI) depicts the value of a given point on the landscape relative to others based on its ability to support plants, animals, and the natural processes that sustain them. To facilitate this comparison of one area with another, units called IEI-acres are used throughout CAPS analysis. One IEI-acre is equivalent to an acre of cells-roughly five cells-with a perfect score of 1. One IEI-acre can also be comprised of 2 acres of cells each with a score of 0.5.For example, consider the town of Townsend with a total land area of 21,100 acres. In 1971, Townsend had an IEI score of 12,000, i.e., the sum of the cells in the town's 21,100 acres added up to 12,000 IEI-acres. By 2005, Townsend's score had dropped to 8,700 IEI-acres, which can be thought of as a loss of 3,300 acres of land with high ecological integrity. This loss occurred throughout the entire acreage of the town rather than on just 3,300 acres; but it enables comparison of Townsend with other towns and allows calculation of the change in IEI over time.
Direct vs Indirect Loss in Ecological Integrity
The direct impacts of development can be thought of as the impact that the building footprint has on the ecological integrity of an area. In a previously forested area, the IEI score will be dropped to zero directly under the home or building footprint. In contrast, the indirect impacts of development can be measured by examining the IEI scores in all places that remain in a natural state. The forests that surround a new subdivision, for instance, are still present, and will have scores that are greater than zero. However, their ecological integrity has been diminished. Invasive species such as multiflora rose and bittersweet will likely be introduced via humans. Domestic pets, primarily cats and dogs, will impact the surrounding woodland as they venture into the forest. Other wild predators that "follow" humans such as cowbirds, skunks, and raccoons will also have impacts on species that were previously present. Fragmentation is another example of an indirect impact of development. Interior forest dwelling species, such as the Scarlet Tanager, will no longer be found adjacent to newly built homes.The CAPS model allows us to tease apart the direct impacts of development from the indirect impacts.