[Coral-List] Explosive growth of Sargassum in the Caribbean

[Alina Szmant]

Thanks Gene for once again weaving the data into a cohesive scenario that starts with:  too many people doing what people do best.... disturbing the natural environment to grow food and other human life necessities. The more people the more disturbance. And this has been going on for millenia.  After all, humanity started in Africa. Most of what you describe has been happening long before the industrial revolution and the rapid increase in greenhouse gas concentrations responsible for recent global warming.  Anthropogenic climate and environmental change and degradation has been occurring for much longer than the rise of global temperature since the boom in use of fossil fuels. And coral reefs are not the only ecosystems affected by human activity.  If you could ask the Sargassum how they feel about all this, they would tell us they love it! To paraphrase a great line from Encanto ("We don't talk about Bruno"): humanity doesn't want to talk about human overpopulation and the cumulative impact of now 8 billion people going about their daily business. There were only 2 billion people on Earth 100 years ago. Not wonder everything is falling apart! Only 4 % of mammal biomass is made up of mammal wildlife. What happened to all the wildlife? They have been killed off as food or decimated by loss of habitat. Their biomass has been replaced by humans and our food animals (plus a few % of pets).

Can't save coral reefs if we have a bigger structural problem to deal with. And yes, social inequality and inequity is a contributing factor but not the main one.



Dr. Alina M. Szmant,  CEO
CISME Instruments LLC



-------- Original message --------
From: Eugene Shinn via Coral-List <coral-list at coral.aoml.noaa.gov>
Date: 3/13/23 1:19 PM (GMT-05:00)
To: coral-list at coral.aoml.noaa.gov
Subject: [Coral-List] Explosive growth of Sargassum in the Caribbean

    As a geologist/biologist diving the Fla Keys and much of the
Caribbean long before the coral-list, Brian LaPointe, and Marine
Sanctuaries existed, I have watched corals diseases develop and other
crises come and go. HoweverI do not recall a time when Sargassum growth
exploded such as it has in the past 2 decades. Of course there were no
satellites for observing the explosive growth back then, nevertheless we
would have experienced abundant floating seaweed accumulating on beaches
such as it has in the past 2 decades.During these recent decades  the
explosive growth has been building year after year. Now the newest area
of weed forms a belt stretching from West Africa to the Caribbean and
beyond and it keeps enlarging. The Amazon and other rivers have often
been blamed in the past even though it seems difficult for those waters
to reach West Africa. Let’s see, can we blame ballast water and/or
cruise ships? Climate Change? Upwelling? Cosmic Rays? There must be
something out there that affects that region on a yearly basis. Whatever
it is satellite images indicate it is coming from Africa, especially
during our summer months. I once read some technical papers that stated
the Amazon Rain Forrest receives its essential nutrients mainly during
our winter months. It seems there is a this red/brown powder that
accumulates on limbs and leaves high up in Amazon forest trees. Because
of it some limbs even sprout rThat powder has been shown to contain
essential nutrients. What is it? During our summer months that belt of
powder moves northward and forms a thin soil over the prevailing
limestone of Caribbean Islands. Some even reach the Florida Keys and
Bermuda. It forms a thin hard laminated red/brown crust in the Florida
Keys that has been forming for several thousand years. That crust
contains clay minerals not native to the Keys, or Bermuda. We even have
an agricultural area west of Miami called the Red-lands. I wonder what
it is and how did it get there?

Of course long-time readers of the list know exactly what I am writing
about. Just suppose that stuff gets sprinkled on the water forming a
belt that spans the Atlantic Ocean. I wonder if it might stimulate the
growth of a floating plant held afloat by small gas filled floats?

Why had it not affected the seaweed, and the corals, or caused red tides
in the past?  Dr. Joe Prospero, now retired from the U. of Miami Marine
Lab  monitored
African dust flux at Barbados starting in 1965. That  monitoring is
on-going. There was little dust in the past when there was far less
people/agriculture in the Schell desert of North Africa and less
pesticides used to control Locusts outbreaks and mosquitoes. There was
also a hundred-mile-wide lake Chad  there in 1960 that has evaporated
down to only a few miles wide. It’s exposed lake bed, and whatever had
accumulated in it, is now blowing across the Atlantic. Need I say more?

After all these years I keep wondering why some organization has not
studied the situation? We at the USGS monitored and cultured live
bacteria in the dust and noted the presence of numerous viruses in the
late 1990s. While the military followed our work, because of bioterror
implications, there was little interest within our organization. Only
the US Academy of Environmental medicine appreciated the work because of
the clear evidence of medical effects on humans, especially on Caribbean
Islands. Trying to understand why there was so little interest in the
projectI keep coming back to the fact that no one is  going to make
money determining if that dust is the cause of coral, and medical
effects. Who benefits if you can’t stop it? Of course the many thousands
with respiratory diseases in the Caribbean and Eastern Bahamas might
benefit but does that put any money in anyone's pocket? And what can be
done to stop it?  Oh Well, I will continue to watch and wait. I thank
Doug Fenner for pointing out this latest explosion of Sargassium and
will wait for his short  reply. Gene
_______________________________________________
Coral-List mailing list
Coral-List at coral.aoml.noaa.gov
https://coral.aoml.noaa.gov/mailman/listinfo/coral-list