Sargassum change of sea currents due to climate change. Also, nutriments from agricultural fertilizers and wastewater from the cities that end up in the sea could also make the algae bloom. Sargassum Sargassum is a genus of brown (class Phaeophyceae) macroalgae (seaweed) in the order Fucales. Numerous species are distributed throughout the temperate and tropical oceans of the world, where they generally inhabit shallow water and coral reefs, and the genus is widely known for its planktonic (free-floating) species. Most species within the class Phaeophyceae are predominantly cold-water organisms that benefit from nutrients upwelling, but the genus "Sargassum" appears to be
Sargassum and "S. fluitans") have become holopelagic—reproducing vegetatively and never attaching to the seafloor during their lifecycles. The Atlantic Ocean's Sargasso Sea was named after the algae, as it hosts a large amount of "Sargassum". "Sargassum" was named by the Portuguese sailors who found it in the Sargasso Sea after the wooly rock rose ("Halimium lasianthum") that grew in their water wells at home, and that was called "sargaço" in Portuguese (). The Florida Keys and its smaller islands are well known for their high levels of "Sargassum" covering their shores. Gulfweed was observed by Columbus. Although it was formerly thought