Risks to Wildlife and Natural Habitat <br />0 ur planet is now in the midst of a major extinction event-the first mass <br />extinction since the age of the dinosaurs 65 million years ago." Although <br />many Americans are aware of the rapid loss of plant and animal species, much of <br />the public debate has focused on resource extraction industries or farming and grazing <br />operations in the world's remote [andscapes.'° In fact, the United States has a rich diversity <br />of plants and animals, and is a world leader in the diversity of certain kinds of wildlife. <br />Unfortunately, nearly one third of the nation's plant and animal species are at risk, and <br />more than 500 U.S. species are missing or may already be extinct." The extinction crisis is <br />not just a distant problem; it is occurring close to home. <br />The primary threat to most of these species is the destruction or degradation of the <br />habitats on which they depend. While many human activities-from agriculture to military <br />training-can alter natural habitats, the conversion of green space to urban and suburban <br />uses is the fastest growing threat to the nation's wild species. Nearly three quarters <br />of Americans already live in urban or suburban areas, and the U.S. is projected to see <br />continued growth in metropolitan area populations." Urban and suburban areas now cover <br />64 million acres, having grown by nearly 300 percent since 1955, while population has risen <br />by only 75 percent." <br />The nation's wildlife heritage is not j ust restricted to the last remaining pristine <br />in the western and southern United States have not only given rise to extremely diverse <br />biological communities, including many localized and vulnerable species, but have <br />also been attractive for human settlement. Consequently, many of the regions with the <br />greatest number of imperiled species coincide with some of the largest and fastest <br />growing population centers. This overlap is bad news for the survival of many species. <br />For instance, a recent National Wildlife Federation (NWF) study of California's wildlife <br />habitats. Prime farmland, forests, wetlands, and prairie grasslands in <br />and around cities and suburbs provide numerous ecological services, <br />and are home to many imperiled species. These areas have enormous <br />potential for species restoration as well, so long as they are protected <br />from development. Even those lands that will never be restored to <br />natural conditions often serve as essential buffers for nearby wildlife <br />reserves or connecting corridors between reserves. For example, in <br />south Florida cattle ranches with a mosaic of forest patches provide <br />valuable habitat for the endangered Florida panther and the Florida <br />black bear. <br />A new analysis of NatureServe's rare and endangered species data <br />finds that three-fifths (60 percent) of the nation's rarest and most <br />imperiled species occur in designated metropolitan areas (Table <br />2). Of particular importance are the 35 fastest growing large metro <br />areas, which are home to nearly one-third (29 percent) of the nation's <br />imperiled species, despite only comprising 8 percent of the total land <br />area in the lower 48 states. The warm climates and varied topography <br />