Updated: Sep 17, 2020
So sargassum is a big thing right now. It's a nuisance for beach hotels and other businesses but what is it and how bad could it be? Sargassum is technically a form of algae (seaweed) that forms into mats in the ocean and grows… and boy has it been growing lately!
Look at these 2 pictures of the same spot now and 8 years ago. I used to jump off this tree into crystal clear water and now if you could actually see the water you'd notice the changes that have occurred. So much that there's a concrete break wall here now.
So is sargassum good or bad? Well it's complicated. On one hand it's good because some marine creatures can eat it, live and nest in it. A handful of species like turtles use it for a nursery. It helps block wind blown sand to prevent beach erosion and it could have some use in the medical field. On the other hand it's ugly, it stinks and can be bad for marine life when garbage collects in it. Too much of it can stop nesting turtles from reaching the shore and hatchlings from reaching the ocean. It's horrible for tourism, no one wants to hang out on a rotten, smelly beach. Worse yet, when it rots it can produce harmful bacteria that can be irritating to skin and lungs and there have even been recent reports of it killing fish near the shore. What I see happening where we are in San Pedro is that in the process of removing it from the beach a lot of the sandy beach has been scooped up with it, which would explain the new break wall.
So what’s causing it and what can be done to manage this influx of it? No one really knows for sure why there’s been such a large amount of sargassum plaguing shorelines lately but some possibilities include climate change, pollution and changes in wind and currents. How can it be managed? Unfortunately just by constantly removing it even though picking it up also takes the beach with it… sigh.