Indirect impacts to desert tortoise populations and habitat are also known to occur in areas that interface with intense human activity. Some of the most apparent threats are those that result in mortality and permanent habitat loss across large areas, such as urbanization, and those that fragment and degrade habitats, such as proliferation of roads and highways, off-highway vehicle activity, poor grazing management, and habitat invasion by non-native invasive species. Since the 1800s, portions of the desert southwest occupied by desert tortoises have been subject to a variety of impacts that cause habitat loss, fragmentation, and degradation, thereby threatening the long-term survival of the species. The Present or Threatened Destruction, Modification, or Curtailment of Its Habitat or Range The following is an overview of the threats to the Mojave desert tortoise and its habitat by the five listing factors used to determine the desert tortoises' protection under the Endangered Species Act.ฤก. These factors are: 1) destruction or modification of its habitat 2) overutilization for commercial, recreational, scientific, or educational purposes 3) disease or predation 4) inadequacy of existing regulatory mechanisms and 5) other natural or manmade factors. Fish and Wildlife Service evaluate the role of five factors potentially affecting the species. In determining whether to list, delist, or reclassify (change from endangered to threatened status, or vice versa) a species under the Endangered Species Act, the U.S.