Secrets Of Sargassum

EXCLUDING FRAGILE CORAL REEFS, aging shipwrecks and massive seamounts, the ocean is a rather featureless expanse. Off the coast of Florida and across much of the tropics, fish migrations are largely dictated by prevailing currents. Caught in the same gyres, floating ecosystems of sargassum seaweed are the basis of life that provide structure and sanctuary for a host of predators and prey.

Comprised of two species, Sargassum natans and Sargassum fluitans, sargassum is a actually a type of brown macroalgae. These dense, holopelagic floating structures consist of branched, leafy vegetation and gas-filled floats allowing the marine plants to drift near the surface where photosynthesis can occur.

While providing essential refuge and safe breeding grounds for juvenile pelagics, sargassum also offers safety and security to numerous species of marine animals including fish, birds, sea turtles and marine invertebrates. As an intricate offshore marine ecosystem, sargassum is perhaps one of the most important structures in the entire ocean.

At times floating mats of seaweed can stretch for miles, with a range of organisms found within close proximity of fertile weed lines. In fact, marine biologists have determined that healthy sargassum seaweed can harbor over 100 species of fish and fungi, as well as over 145 species of marine invertebrates. Of all the fish that travel with these floating mats of vegetation, filefish are the most common individuals, closely followed by various jack and triggerfish that reside alongside these structures during at least one stage of their life cycles.