Sargassum seaweed, a floating brown algae that is often found washed up on shorelines from Florida down to South America, are creating a barrier for hatchling sea turtles trying to get to the sea. Sargassum seaweed, a floating brown algae that is often found washed up on shorelines from Florida down to South America, are creating a barrier for hatchling sea turtles trying to get to the sea. The study looked at the physiological response and physical performance of the loggerhead sea turtle (Caretta caretta), leatherback turtle (Dermochelys coriacea) and the green sea turtle (Chelonia mydas) as they traversed pathways with and without sargassum. Loggerhead turtles took 91 percent longer to crawl through the light sargassum and 175 percent longer in the heavy sargassum. “For sea turtle hatchlings, reaching the ocean is already a race against time – and survival.