If you live in Galveston or visited our island over the past decade, you most likely have had an experience with seaweed. Even though it sometimes disrupts our surfing, swimming, or beach activities, seaweed is a very valuable resource for wildlife. When seaweed is removed, the beach atmosphere changes, leaving many animals and plants without a place to live and eat. Sargassum is on our beaches; the brown or dark green macroalgae that floats on the surface of the ocean and is carried in with the tide. If you look closely, you are able to see its leafy structure with many branches and circular balls. The balls are gas-filled with oxygen, which helps the plant with overall buoyancy and the ability to float on the surface. Each year, during late spring and summer months, large mats can wash up along the Gulf of Mexico’s coasts. These mats come from the Sargasso Sea in the North Atlantic Ocean, which is surrounded by four ocean currents.
Many species call sargassum home, including sea turtle hatchlings, fish, shrimp, crabs, and more. Most blend in with the sargassum, their bodies camouflaging. Birds of all kinds search the sargassum for these species to eat. Sea turtle hatchlings fight for their life trying to make it to these sargassum mats, and after arriving, it becomes their habitat for the next few years. While in these mats, these species not only receive protection but food as well. After a couple years of floating, sargassum mats lose their buoyancy and sink to the bottom of the ocean, becoming food for animals in the deep. The sargassum also washes ashore through currents and wind. Once on the beach, its seeds and nutrients contribute to dune plants. This vegetation is an important aspect of the shoreline, because it protects against storm surges and flooding.
Having sargassum on beaches is great for beach combing, or searching the beach for items. The wrack line is the line of debris left on the beach by high tide, and is filled with sargassum, debris, and possible ocean treasures. You can find shells, sea beans, organisms and maybe even valuable items that were lost at sea. If we remove this sargassum, we are removing wildlife, nutrients, and the potential for a safer coast. Protecting our shoreline and species that live here has become our responsibility. We need to learn to give or let be instead of take. Next time you’re out on the beach, I hope you will be able to see the value of sargassum, the floating ecosystem within our oceans and bays that brings many positive benefits to Galveston island for both humans and wildlife. If you encounter sargassum, pick it up, shake it out, and discover the wonders of this complete ecosystem.