Historically, statutes protecting animal habitats have blocked many projects. This is a specialty area not addressed specifically by GIS. There are many variables within this and a closer look has to be made – indeed, the category requires two separate outlooks – that of endangered species and that of all others.

Those who do not want the project to go forward usually challenge projects built within the confines of the habitat of an endangered species. Two famous projects include the Tocks Island dam where the brown snail-darter fish blocked the construction of a major hydroelectric dam. A second location is the case of spotted owls in the forests of the Pacific Northwest where lumbering is a major part of the local economy. The locations of endangered species are not readily available. This is purposely made difficult to find as people will often go to these sites to "help" the animals ands wind up destroying them or will try to prevent all future development in the area without looking at the ecological alternatives. If federal monies are required in any phase of the project construction or if it meets certain local restrictions, then an environmental impact statement is required and this information would be thoroughly searched.

All other species are lumped together. The greatest concern is habitat fragmentation. This is the case where a tract of land that is the habitat for a given species is broken up into smaller segments. This may be done through development, highway construction, pipelines, etc. Some animals have few problems adapting to these new environs. Most birds, squirrels, raccoons and other small mammals can adapt. However, large mammals such as deer and bear may find it more and more difficult to find feeding areas and to follow natural migration routes. These individual problems must be taken into account.