By the Numbers Wildlife Conservation Reducing human impacts on wild animal populations is critical to the futures of a number of species in our parks 468: Current number of endangered animal species in the United States. 176: Current number of threatened animal species in the United States. 476: Current number of endangered or threatened animal species in the United States with active recovery plans. 42: Percentage of endangered or threatened animal species in the United States in danger due to invasive species. 1.5: Number of degrees of average worldwide temperature rise since 1900. 2-10: Estimated number of degrees of average worldwide temperature rise before 2100. 8: Number of inches of average sea level rise since 1900. 854: Number of animal species listed as " critically endangered " by the International Union for Conservation of Nature in 1998. 2,129: Number of animal species listed as " critically endangered " by the International Union for Conservation of Nature in 2012. 20 Parks & Recreation | N O V E M B E R 2 0 1 3 | W W W. N R PA . O R G Sources: The International Union for Conservation of Nature Red List (www.iucnredlist.org), The National Wildlife Federation (www.nwf.org), U.S. Fish & Wildlife Service Endangered Species Database (www.fws.gov/endan gered/species).