Sea levels worldwide are rising as warming temperatures melt ice and expand ocean water. Average global sea levels could rise as much as 6.5 feet by 2100. These rising waters pose a widely acknowledged danger to America’s coastal cities; but sea-level rise also threatens our nation’s biodiversity. The United States is home to 1,383 federally protected threatened and endangered species, many of which depend on coastal and island habitats for survival. As greenhouse gas pollution builds up in the atmosphere, rising oceans and increasingly dangerous storm surges will threaten already endangered animals that inhabit coastal wetlands, beaches and other vulnerable ecosystems.