Anyone who looks at the sargassum seaweed cluttering the once beautiful sandy beaches of many Caribbean islands will have that sinking feeling of having their scenic sand and near-shore waters badly affected.

We have spoken about it many times, and much has been spent on the very difficult removal of the seaweed from the sand using special vehicles, backhoes and a lot of trouble and cost.

At my last visit, I had the same feeling and wondered what we were missing. Are there easy and cost-effective methods of removing the seaweed from our shore? Is there an outside-the-box solution no one has found? What are the thinking and analytical methods that would give a solution that has been missed by millions?

 

‘Series of questions’

I then asked myself a series of questions whose answers led to some very simple yet amazing thoughts — and perhaps a stunning result.

The first question: With all the seaweed in the world, why is this particular type of seaweed a problem? The answer is that other seaweed is not as plentiful on our beaches.

Another question followed: If the normal seaweed is okay and this one is not good, why is this one here?  The answer is that it came from far away. Okay: very easy so far.

The next question: How did it get here from so far away while the normal seaweed is always near shore and most times on the seafloor? Well, this one floats. Then it struck me: The problem with sargassum is that it floats. Then I devised a theory: Seaweed on the ocean floor does not travel around the world as much, but the one floating on the surface is carried by the wind and waves.

 

Stop the floating?

So the big question that comes to mind is this: Can’t we just stop the seaweed from floating when it gets nearby? (We don’t want to go miles out to block it, but when it gets near enough, can we just go out and do something to stop it from floating onto the beaches?)

At first, this seemed like a dead-end idea: I assumed that the seaweed is 100 percent buoyant and would not sink. Then I did an internet search for “why does sargassum seaweed float,” expecting to find that the entire plant is lighter than water. But I learned that the sargassum only floats because of small air bladders known as pneumatocysts.

So I went and got a bucket of sargassum to look at the bladders. I first got some from the sand and put it in the bucket. But not much floating was happening. So I asked a fisherman to get some from out at sea. It floated. The bladders, I realised, seem to fall off when the seaweed gets churned in the waves on the sand.

It seems that the bladders that survive the gentle up and down of the waves on the far oceans easily fall off when faced with the swash of waves onto the shore. That’s when I realised the obvious solution for sargassum.

 

An ‘obvious solution’

 

Suppose that whenever the seaweed is spotted about 1,000 feet from shore (perhaps by drones), we send out a couple of boats with a device that sort of rakes or disturbs the surface of the water and the floating sargassum. Perhaps the fragile pneumatocysts would separate and the sargassum would be unable to float. Then it would slip to the seabed and be unable to make the 1,000 feet to our sand. We would not have to knock off all of the fragile pneumatocysts — just enough for them to sink. To do that, we could send boats out with some sort of floating device resembling a large rake, which would not gather the seaweed but just churn the water. We could drive the devices up and down for about two hours over the seaweed — and presto!

 

 

Mr. Hinds lives in Barbados, which, like many Caribbean islands, has experienced sargassum problems similar to the ones faced by the Virgin Islands.