The populations of Florida’s west Indian manatees and green sea turtles have rebounded from perilously low levels, officials say, and are no longer at risk of extinction. Since they were identified as endangered under the Endangered Species Act in 1991, and offered protection, Florida’s manatee population has gone from 1,267 to about 6,300. That’s a 500% increase. On Jan. 7, the U.S. Fish & Wildlife Service suggested downgrading their status from “endangered” to “threatened.” The population of Florida’s green sea turtles has also recovered. In 2001, scientists tracked 198 nests at their main nesting site, the Archie Carr Wildlife Refuge. Last year, they found 14,152 nests. In 2015, the U.S. Fish & Wildlife Service proposed reclassifying those green sea turtles in Florida and also on the pacific coast of Mexico to “threatened.” This has prompted Florida officials to begin reviewing the need for boating speed limits near manatee protection zones. But critics warn that scaling back protections for these creatures is premature. Dr. Llewellyn Ehrhart, professor emiritus at University of Central Florida, says a reclassification could lead manatees and green sea turtles into an extinction vortex. “It doesn’t make much sense to produce a yo-yo effect. Take the protections away for a while and have people start exploiting them, and the population becomes decimated, then you upgrade them again,” Ehrhart said.