Threatened and endangered species geography: characteristics of hot spots in the conterminous United States

摘要: An estimated global extinction rate that appears to be unprecedented in geological time (May 1990) has heightened concern for the increasing number of rare species. Moreover, this elevated is being attributed activities humans rather than some calamitous natural disaster (Pimm et al. 1995). Conservation efforts slow biodiversity loss have traditionally focused on species with few remaining individuals, based assumption they are most vulnerable (Sisk 1994). Consequently, rarity been used as an important criterion identifying which should focus conservation efforts.