Sargassum weed.

capnsensible

capnsensible

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Now I'm posting this as a sailor for other sailors who may be considering a transatlantic crossing this year. I've seen it become a bigger and bigger problem on east to west crossings I've made over the past two decades.

It's no longer confined to the Sargasso Sea gyre, but is dominant the whole way across and much further south. The reasons are problematic to discuss here......climate, politics, yadda yadda. But the fact remains its becoming a real problem, destroying Carribean beaches and ecosystems. And when it rots ona beach it smells worse than a sumo wrestlers jockstrap.

I'm on the eastside of the Atlantic at 29 North. Its not a problem here but I'm already starting to see the usual annual arrivals that will be setting off in a few months to dice it eith the weed. I'm aware the moderators might take the hump, but I'm gonna link this report as I think it's a safety warning for cruisers.

Sargassum, the brown tide that is invading the Caribbean

Hope it does stay within the rules.
 
I always thought one went to the Caribbean for an entirely different sort of weed.
But between this and the killer whales, ocean sailing is getting a lot more complicated.
 
The sargassum weed is a huge problem here now, especially so on the bays on the east coast where it piles up, as illustrated in this link -
‘Unbearable’ - Barbados Today

In the past the larger / wider beaches further north have generally managed to munch up / absorb the seaweed over time, but now even they cannot cope, and it is piled up on these as well. I only take my dogs for a walk on the beach at low tide now, as then there is a narrow strip of sand to walk on - it is not much fun clambering through deep drifts of weed.

The west (leeward) coast occasionally gets a bit of weed if we have a south wind, but it is generally clear. However there is a lot of weed on the south coast tourist beaches as well, and our visitors are not amused :(
 
That article shows just how much the problem is no longer creeping but running. I've seen it all the way across to Panama.

Let's hope the smart guys figure out how to use it as a natural resource... although scientists aren't exactly popular on these forums.
 
Slowboat35 said:
I'm waiting with bated breath to discover how politics is involved in causing a plague of sargassum weed...
Click to expand...
Politics produces a lot of hot air, mostly because all politicians lie when the open their mouths and boy do they like talking
,. It's mostly CO2, when breathing out to talk, plants like CO2, they absorb it and need it to grow.
QED politics causes sargassum to grow.
 
We crossed East to West last December. The weed didn't really kick in until the last 1000nm. It was impossible to run the towed turbine once we entered this area. If you rely on a towed turbine then you really need to consider another solution to charging you batteries.
We had friends that crossed in a Allures 45. They got so much weed around their unprotected prop (twins rudders) that they had to go over the side to clear it. On vertical front keels with bulbs on the bottom it also hangs on pretty well. Friends racing in the Caribbean 600 had to go over the side to clear it. Our Windpilot self steering gets a build up around the servo pendulum. We have an extra long wooden boat hook that I push the weed down and off the bottom with. It's not a major problem on the servo pendulum rudder as the build up only stops you getting full power to the steering. Clearing it every few hours was not such a big issue. If you run a generator or engine for charging them regular inspection of the strainer is essential.
 
geem said:
We crossed East to West last December. The weed didn't really kick in until the last 1000nm. It was impossible to run the towed turbine once we entered this area. If you rely on a towed turbine then you really need to consider another solution to charging you batteries.
We had friends that crossed in a Allures 45. They got so much weed around their unprotected prop (twins rudders) that they had to go over the side to clear it. On vertical front keels with bulbs on the bottom it also hangs on pretty well. Friends racing in the Caribbean 600 had to go over the side to clear it. Our Windpilot self steering gets a build up around the servo pendulum. We have an extra long wooden boat hook that I push the weed down and off the bottom with. It's not a major problem on the servo pendulum rudder as the build up only stops you getting full power to the steering. Clearing it every few hours was not such a big issue. If you run a generator or engine for charging them regular inspection of the strainer is essential.
Click to expand...
On my last couple of crossings I've found huge rafts of it that you can't go around easily. Especially at night. The drag caused by it getting around the keel, propellor and rudder was significant. There can be an awful lot of other human junk that gets caught up in it that's cause for concern as well.......

I flew over a couple of years ago to pick up a yacht for the return trip. As we pit stopped in Barbados on route to Antigua the rafts of the stuff seen from the air covered an awful lot of ocean.
 
Increasing water temperature, increased CO2 content in the oceans, increasing acidity levels and quite possibly increased nitrate levels will all have an effect on any marine growth. This is all slowly coming back to bite us in the rear.
The answer has to be to find an alternative use for it.
 
chrishscorp said:
Increasing water temperature, increased CO2 content in the oceans, increasing acidity levels and quite possibly increased nitrate levels will all have an effect on any marine growth. This is all slowly coming back to bite us in the rear.
The answer has to be to find an alternative use for it.
Click to expand...
Evidently, when cattle feed is supplemented with seaweed, it dramatically reduces their methane emissions.
 
Not really a thread drift but there seems to be an awful lot of thin floating seaweed this year, in the Channel Island areas and further South. The propellors needed clearing on a daily basis.
 
The ideal solution would seem to be using Sargasso weed as a fuel for use in a biodigester. There has been a fair amount of research into this idea, but it’s not without its issues; namely that it has to be used in conjunction with other organic waste and what’s left has to be treated before it can be used as fertilizer.

Enhancing biogas production from caribbean pelagic Sargassum utilising hydrothermal pretreatment and anaerobic co-digestion with food waste

I also recall from a trial in Guadeloupe or Martinique that the weed had to be gathered at sea; once it’s all sandy it has to be washed before use.
 
capnsensible said:
On my last couple of crossings I've found huge rafts of it that you can't go around easily. Especially at night. The drag caused by it getting around the keel, propellor and rudder was significant. There can be an awful lot of other human junk that gets caught up in it that's cause for concern as well.......

I flew over a couple of years ago to pick up a yacht for the return trip. As we pit stopped in Barbados on route to Antigua the rafts of the stuff seen from the air covered an awful lot of ocean.
Click to expand...
Yep, I have sailed through numerous enormous rafts that are 100 metres across and about 2ft thick. We don't get problems with catching on our keel as the leading edge is angled. It seems to remove itself without issue. The other human detritus is always a concern. On the last trip we got fishing net discards around the towed generator three times. The third time was enough to snap the aluminium casting and put it out of action. A thirty foot length of fishing net was a massive load. Humans are doing an excellent job of destroying the planet
 
Mudisox said:
Not really a thread drift but there seems to be an awful lot of thin floating seaweed this year, in the Channel Island areas and further South. The propellors needed clearing on a daily basis.
Click to expand...
There’s lots in the baie de Saint Brieuc. As mentioned above, with a twin rudder set up we have it regularly attaching itself to the screw or the rudders.
 
geem said:
Yep, I have sailed through numerous enormous rafts that are 100 metres across and about 2ft thick. We don't get problems with catching on our keel as the leading edge is angled. It seems to remove itself without issue. The other human detritus is always a concern. On the last trip we got fishing net discards around the towed generator three times. The third time was enough to snap the aluminium casting and put it out of action. A thirty foot length of fishing net was a massive load. Humans are doing an excellent job of destroying the planet
Click to expand...

It was discarded fishing mat that finished off Alex Thomson’s participation in the last Vendée Globe.
 
Mudisox said:
Not really a thread drift but there seems to be an awful lot of thin floating seaweed this year, in the Channel Island areas and further South. The propellors needed clearing on a daily basis.
Click to expand...
I wonder whether that is a result of the prolonged hot weather we have recently had ? I noticed a lot the other week in Christchurch bay.
 
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