Artificial light is not conventionally thought of as a source of contamination, but its disruption of habitats and behaviors of plants and wildlife have brought it into the spotlight as a threat to the environment. Excess light can affect nocturnal predators that need the dark to hunt, wildlife that require darkness for protection and reproduction, and the navigation of birds and other avian wildlife. Unfortunately, due to population growth and unawareness of correct lighting fixtures and practices, dark skies are becoming extinct.

Mount Desert Island, an island off the coast of Maine, is home to Acadia National Park. The park, rich with a variety of wildlife and a diverse landscape, is made up of mountains, beaches, wetlands, forests, and tidal areas. Neighboring the park is Bar Harbor, a town full of lobster boats, restaurants, and hotels.

Last winter, students from nearby College of the Atlantic (COA) conducted one of the first endeavors to map light pollution locally using geographic information system (GIS) software. The main objective in mapping levels of brightness on Mount Desert Island was to create a visual depiction of the sources of extraneous light, quantify that light, and design a method for mapping light pollution locally. Local maps of light pollution would enable decision makers to develop rules to restrict light use, change lighting fixtures in polluted areas, and target ways their own light use can be reduced.

Gathering their data at night, students drove around the island multiple times, measuring the brightness of the sky using a sky quality meter. Averaging three data readings from each of their 140 data points around the island, they used the ModelBuilder application in ESRI's ArcInfo software to create a map that demonstrates the amount of light pollution on the island. In the Bar Harbor area their map shows some of the color red; a concern for Acadia Park officials because red represents a densely populated area such as New York City.

The methodology that the students designed will provide online resources about light pollution in the Mount Desert Island area as well as give Acadia National Park staff the information needed to implement change in lighting fixtures. In addition to providing this information locally, the students hope to make data like this available online. Maps created using their procedure and GIS technology can increase awareness of light pollution in communities and across the globe. Awareness is the first step in providing alternate lighting options that will preserve the earth's wildlife and conserve its energy resources.

Acknowledgement: Research conducted by COA students Nicholas Bacon and Apoorv Gehlot under the supervision of COA GIS instructor Gordon Longsworth.