Sargassum is a genus of seaweed common in the Caribbean. Though it may appear like one, it is technically not a plant and is instead a form of multicellular algae. The nodules visible are filled with gas and help the seaweed float.Sargassum typically gathers in large mats. The common presence of such mats in the Atlantic ocean near the Caribbean caused the region of ocean to become nicknamed the Sargasso Sea. While these mats form crucial habitat for a large number of creatures, in recent years rising temperatures have caused their population to explode. This has in turn caused issues with large amounts of Sargassum washing ashore, clogging beaches, and choking out other forms of life. In the worst cases, it becomes thick enough to disrupt navigation by tangling with the propellers of small craft.
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