Conservation biologists have come to recognize the importance of GIS in their discipline. Geographic Information Systems (GIS) have become a useful tool in the field of landscape ecology. A common application of GIS is the generation of landscape indicators, which are quantitative measurements of the status or potential health of an area (e.g. ecological region, watershed or county). With the increase in available landscape data from satellite imagery and public agencies (most notably the USGS), GIS has become an irreplaceable tool in the spatial analyses performed in conservation biology.