CNN  —  The tallest animal in the world is in trouble. Giraffe populations are declining at such an alarming rate — from habitat loss, poaching, urbanization and climate change-fueled drought — that US wildlife officials announced a proposal on Wednesday to help protect several of the species. The US Fish and Wildlife Service proposed listing many giraffe species as either endangered or threatened. It’s the first time the long-necked mammals, native to Africa, would receive federal protections