The Sargasso Sea

In this episode of Stuff to Blow Your Mind, Robert and Joe explore the sargassum seaweed and the many strange and amazing organisms that call it home.

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Episode Transcript

Speaker 1 (00:03):
Welcome to Stuff to Blow your Mind, the production of
My Heart Radio. Hey, welcome to Stuff to Blow your mind.
My name is Robert Lamb and I'm Joe McCormick. And
today we're going to go into the wettest of the woods,
the saltiest of the woods. Today. The woods are salty,

(00:25):
dark and deep. And we have promises to keep and
miles to float before we sleep, because we're going to
be looking at a sort of jungle in the ocean.
That's right. Uh. The ocean. Uh, it knows quite a
mix of environments, from rich coral reefs to desolate deep
sea waste from sunlit shallows to hydrothermal vent heated depths.

(00:48):
Marine organisms, of course, face numerous challenges, but the most
basic demands boiled down to, you know, how not to end,
how not to die, how to prolong. It's era to
quote way for the barbarians, but this is especially true
if you're small or your young organism. You're gonna need
food and you're gonna need shelter. Uh. And there's always

(01:09):
gonna be something trying to eat you. And for a
number of organisms, this is provided by sargassum, a genus
of brown seaweed of sometimes brown, sometimes described as brown
and orange um as well. Discuss there a number of
different species here, But UH sargassum thrives abundantly in the ocean.

(01:30):
It floats free of the ocean floor. It provides a buoyant,
free floating environment that travels on the tides and offers food, refuge,
breeding grounds, nurseries, hunting grounds, et cetera for a wide
variety of organisms. So in this episode, we're going to
discuss the sargassum organisms themselves, the environment that they offer,

(01:52):
some of its benefactors, and also the problems posed by
the so called Great Atlantic sargassum belt. Yeah, and that
last point is interesting because I will say, when you
think of of seaweed, do you think of the macroalgay world,
you don't usually think of it as something that is
particularly economically devastating or or even economically all that significant.

(02:15):
But but that that is not the case for sarcassum.
Yeah as well. It's it's it's an interesting topic to
explore because in its present form it kind of cuts
both ways. It's both vitally important to UH to so
many organisms and a number of organisms that are then
important to us. You know various um, uh, you know
marine species that we depend on, various fish and so forth.

(02:37):
But then on the other hand, uh, in an environment
that is increasingly out of balance, Uh, it also poses
a threat, and it can pose quite a nuisance. So
we'll get into all that. So what got you thinking
about sarcassum for today, Rob, Well, it's because tomorrow's episode
of Weird howse Cinema will entail sargassum and casual mention

(02:59):
of a few of the creatures. One creature in particular
that calls at home. Um. Well, we'll try to save
all of that for tomorrow's episode. But but yeah, that
was probably the first place I heard of sargassum, the
weed of deceit. I was wondering if we should announce
the movie, but maybe we should just make everyone wait
to find out they're going to be wondering. Wait, is

(03:20):
it a Jaws clone where it's a big raft of
seaweed instead of a shark? Is it like the Blair
Witch Project, but instead of getting lost in the woods
of Virginia or wherever it is, you get lost in
the woods of the ocean of the Sargasso Sea. Well
that the truth will just suddenly strike out at them
and there'll be nothing they can do about it. Uh So,
so tune in tomorrow if you wish for that. But

(03:43):
but for this episode, we're going to focus on first
on on sargassum, the the organism. So sargassum glimpsed in
the ocean or on the beach, it might just look
like a big heap of brown mess. But about closer look,
you'll notice that it's composed of branches, leafy bits, and
what looks like plump berries. But they're not berries, So

(04:04):
don't don't pick them. Uh, I mean, I guess you
could pick them. But what they are actually are neumaticists.
These are air bubbles um. Uh. They are part of
the organism held that you know, in in these little
cysts that help it excel at floating around. Right. Because
of course, there are different types of seaweed, and some
types of seaweed spend their life, you know, submerged in

(04:27):
the water, and they might be say, anchored down by
a type of organ known as a hold fast that
is somewhat analogous to like the root ball of a
tree that holds it, except in the case of seaweed,
it would hold clumps of seaweed to the ocean floor.
Not entirely analogous. I mean for many reasons, one of
which is that UH is that the seaweed that we're
talking about today is technically not even a plant. It

(04:49):
is a type of macroalgae, which will explain more about.
But in the case of sargassum, Uh, there are types
of sargassum that are free floating organisms that spend much
or all of their I was just floating on top
of the water to have good access to sunlight, of course,
which they need in order to make their food to survive.
But they've got to just sit there and float on
the top. And they're actually not even anchored to the

(05:10):
bottom at all. They just float out in the open ocean.
And I do just want to stress again that the
genus is sargassum, and there I believe about a hundred
and fifty species um all of sargassum. Uh. The hundred
and fifty number, I got that from the Ocean Foundation,
though curiously I saw some higher numbers out there as well.
I don't know if those were accurate. I'm sticking with

(05:32):
the one, right. So there are different kinds that you'll
find especially in different parts of the oceans around the world. Right. Uh.
And we'll be talking about some key ones though, that
are the most abundant or at least in the end
of the part of the world that we're gonna be
discussing here. So, as I mentioned, sargassum is a brown macroalgay,
so it is different than plants. And how exactly is

(05:54):
it different than plants? Yeah, I think this is also
important to stress because if you don't think much about seaweed,
you might just you know, you know, you might just assume, well, right,
it's some sort of plant that grows in the water. Um.
And I think that you might be reasonable to make
that assumption just based on its physical appearance. And certainly
the word seaweed um, weeds are plants. Yeah, And and

(06:15):
seaweed is also used informally a lot of times to
describe both the algae and some plant organisms. But the
algae are protests, meaning they are uh eukaryotic organisms which
are not animals, plants or fungi um. So land plants,
for their part, they likely derived from fresh water algae

(06:37):
about five hundred million years ago. And algae is of course,
when we look at the just the root of the
word um. They're synonymous with seaweed, as alga is the
Latin for seaweed. Okay, so if you if you just
think about algae like the most I would say, if
I was to go on my own personal life experience,
when I hear the word algae by itself, what I

(06:58):
tend to think of is kind of green en pond scum,
you know, kind of very like something floating on top
of a stagnant freshwater body like a pond or a lake,
that is made of tiny little fibers that just kind
of clumped together, doesn't have any recognizable macro structures the

(07:19):
way larger plants like like flowers or trees would. But
that is not true of all kinds of algae. These
macro algaes that we see in these types of seaweed,
they have more complex structures that are more like the
structures of land plants. So they might have something that
is akin to the stalk of a land plant and
something that is akin to the leaves. In these cases,

(07:41):
they would be algal fronds. Yes, yeah, so yeah, again,
they look very plant like. You can easily look at
them and say, oh, they're they'll leaves, they're the berries.
But uh, at any rate, again, a hundred and fifty
different species of sargassum. Uh, though we're generally gonna be
talking about specific dominant species with in given regions. For instance,

(08:01):
the two varieties found most often in the Caribbean are
Sargassum Natan's and Sargassum fluettans um. I don't think it
would be necessary to remember that, but just know that again,
we're gonna we're probably gonna refer to sargassum a lot,
just generally, but we're gonna ultimately be dealing with specific
species that are dominant within a given a region. So

(08:24):
sargassum reproduces a sexually through fragmentation, a form of a
sexual reproduction in which parents split into fragments and those
fragments then become adults. And furthermore, the Caribbean sargasm species
in particular, and some of these other varieties that are
important are hollow pelagic. That means that they not only

(08:45):
float freely on the ocean, but they also reproduce vegetatively
on the high seas. So they're they're completely in international waters.
You know, they're they're they're they're a monkey knife fight
that the land has no control over. So yeah, but
that would mean that they don't They can do their
whole life cycle without like anchoring to the bottom at

(09:06):
any point or returning to shore or anything like that. Right,
And that's gonna that's gonna becoming important later on. It
get it really gets Nultimately the idea of sargassum being
the wheed of deceit, so it grows abundantly in the ocean,
where it forms vast floating rafts, as it's sometimes called,
though um I don't think these are rafts in the
sense that you could, you know, be a shipwrecked sailor

(09:28):
at sea and climb on top of it or hoist
a sail on it, But essentially just big rafts, big
floating chunks of of the sargassum, all tingled together, stretching
in some cases for miles, and these form in areas
of converging surface currents, and in doing so they create
a vital environment, like re alluded to earlier. But on

(09:48):
top of the environment, the organism itself provides food. According
to the Ocean Foundation, sargassum contributes and estimated six of
the total primary production in the upper one meter of
the water column. Okay, so that would refer to like
different different stages of the food chain. So you've got
the primary producers that are familiar to us. These are

(10:09):
generally photosynthesizing organisms, like like plants on land, you know,
that absorb sunlight to power the chemical reactions that make
their bodies. And then you've got the secondary, uh, characters
on the food chain that eat the primary producers. You
know that that eat plants to survive. The same thing
is true in the ocean. So you've got these primary
producers that are at least near the top of the

(10:30):
water column are going to be basing their their energy
cycle on sunlight to to produce these molecules that make
up their body that that in turn are eaten by
other organisms that are the sort of the secondary organisms
in that food chain. Yeah, it's it's like you said
at the very beginning, this is the forest that we're discussing.
Like in a way, don't think of the ocean itself

(10:50):
as the forest. Think of the think of the sargassum.
These going to these rafts of sargassum as the forest.
Because the ocean, as we've discussed on the show before,
the ocean can be a wasteland, the ocean can be
a desert and um and in that desert, the sargassum
can be the oasis um. It serves as a place
of refuge for various creatures as well as again breeding

(11:10):
grounds nurseries. In fact, it's the primary nursery for a
number of important to human to humans, especially fish species
like the ma ma. And given all of this activity
that's going on at the various creatures that call it home,
sometimes exclusively uh, their home, it's also prime stalking zone
for many marine predators. So both sargasm predators who live

(11:31):
there and have evolved a thrive in its environment, but
also general marine apex predators that are drawn in by
the by by the riches there by the biodiversity. Uh,
let's see if a few other just sort of general
um facts about sargassum. It can survive wide temperature and
salinity variances, and after about a year, those new maticists

(11:54):
that help it to remain buoyant, uh, they lose their
buoyancy and bits of sargassum will then sync to the
sea floor where it will actually end up providing carbon
for various deep sea creatures. So it's not only an
important energy source for the sunlit shallow regions of the sea,
but for the dark depths as well. I guess, serving
as kind of like that that nutrient rainfall that we've

(12:15):
talked about before that rains upon the deep and indeed,
when it washes up on the shore, uh, I guess
for for the most part we're talking about it. If
it's washing up in manageable quantities um, it can actually
nourish beaches, it can prevent sand from blowing away. Uh.
And when it washes up, it also serves as a
food source for various coastal species um. And not only

(12:39):
is it generally not harmful to humans, it's actually edible.
More on that in a bit. UH. There are also
possible biofuel and pharmaceutical possibilities for sargassum um. We'll get
into some of the drawbacks later on, but but one
of the interesting things here is that like the idea
of just sargassum piling up on the beach again in
manageable quality quant quantities does bring to mind that sort

(13:01):
of contest, that disagreement at times over what constitutes the
beach or what the beach should look like. You know,
should there be anything on the beach other than um
human strolling and enjoying their vacation. You know. Uh, you know,
some of the some of the really beautiful beaches out there,
a lot of times they are manicured. You know, things

(13:23):
like seaweed are collected regularly in order to have that
sort of Hollywood beach presented. Uh. And in many cases
there's an argument to me, may then no debris would
be on the beach naturally, and it in the right quantities,
it can be important to keeping the sand from washing away,
keeping the beach from eroding, etcetera. I can see the
point of view that would say, I'm okay with the

(13:44):
beach that has natural debris, but not unmanageable amounts of
natural debris or artificial debris. I mean, you certainly you
know you don't want too many beer cans. That's going
to kind of ruin your beach experience. Yeah, nobody wants
to step on a beer can on the beach, But likewise,
nobody really wants to have to walk over a tin
foot high mound of sargassum like dead, rotting seaweed. Right

(14:05):
right now, Um, we're gonna be getting into the history
of humanity's awareness and understanding of sargassum here and the
first bit I want to share is that you know,
certainly early sailors described sargassum mats, and one individual in particular,
Christopher Columbus. Uh, this was in when abundant sargassum fooled

(14:30):
Columbus into thinking he was approaching land. And I couldn't
find anything that really defined this for me. I don't
know if you did, Joe, but I assume this is
what the term the weed of Deceit refers to the
idea that you might encounter sargassum mats out at sea,
and you could make the same air that Columbus made

(14:51):
and think, oh, look at all the seaweed. Uh, there's
it's thick, it's everywhere. We must be really close to
land at this point. Sure, I don't know that that's
where the name comes from, the that makes sense. Yeah,
So on September Columbus Road, and this is of course
translated quote, we have begun to see large patches of
yellowish green weed which seems to have been torn away

(15:11):
from some islander. Reef. I know better because I make
the mainland to be farther on and then on September
sevent I saw a great deal of weed today from
rocks that lie to the west. I take this to
mean we are near land. The weed resembles a grass,
except that it has long stalks and shoots and is
loaded with fruit like the like the mastic tree. Um, so, uh,

(15:31):
you know, I guess on the on September six, it
sounds like he was like, no, you can't fool me.
We're not that close to land. But on September sevente
he said, nope, we are close to land. Look at
all this seaweed. I had to look up what the
mastic tree is because I didn't know, but it's the
but it's known as Pistachia lentiscus. Ah. Yeah, I looked
up a picture of it as well, and I do
see some some prominent little round fruits that you the

(15:55):
little berries that I assume that's that's what he was
comparing to the what what are actually neumaticists? Yea. As
we mentioned earlier, the neumaticists are these little tiny berry
shaped gas bladders that helped the the seaweed float. But
in this case, yeah, it looks kind of like these
berries in a tree that would have been familiar to Columbus.
I think the looking at the mastic tree apparently is

(16:15):
useful for its resin. So a special note is the
Sargasso Sea. This is a truly vast patch of sargassum.
According to the Ocean Foundation, the Sargasso Sea is sometimes
referred to as the Atlantic Golden Rainforest and the islands

(16:40):
quote unquote uh in the Sargasso Sea can be acres across,
while the regions they occupy can stretch for miles right now.
The Sargasso Sea is interesting because it is the only
real sea in the world that doesn't have any land boundaries.
The Sargasso Sea is a sea within an ocean. It's

(17:01):
uh this patch in the middle of the Northern Atlantic. Basically,
it's just a large patch. If you were to look
at the eastern coast of the United States, uh and
you know in the Caribbean maybe with the bottom edge
down around like Cuba and uh in Puerto Rico, and
then going up along the the coast of North America

(17:21):
up towards Newfoundland, and then you just extend out east
from there. There's this big patch in the middle of
the Atlantic Ocean, which is known as the Sargasso Sea.
Now we should be clear that it is not like
blanket covered in sargassum seaweed, but there are It is
known for having large rafts of sargassum seaweed within it,

(17:41):
and the Sargasso Sea is interesting in a number of ways.
One thing about it is it's known for having UH,
for being a place where ships can easily become be calmed,
and this is a risk that people who are not
very familiar with sea voyages might not think about very often.
But back in the days of sailing, one thing that

(18:02):
was really dangerous is if the winds die down and
you can't say, you know, there's nothing to propel your
ship in the direction where it needs to go. All
throughout the the Atlantic around the Sargasso Sea, there tend
to be these wind currents. You know they're there are
winds that will blow you UH, that will blow you
east to west, down from the from the coast of

(18:22):
Africa down towards UH, towards the Caribbean, and towards the
northern coast of South America. And then there are winds
and currents in the ocean that lead up north along
the east coast of North America. And then if you
go up north from there, there are winds and currents
that will lead you back towards the east from the west.
So essentially you create this box in the middle of

(18:44):
the North Atlantic that is surrounded by currents that go
in a circle around it. And this isn't often known
as the North Atlantic gyre. Now, anyone who's ever watched,
you know, any number of sailing movies or TV shows,
or any TV show that includes like a a voyage
by sale across the ocean. This is a This is

(19:06):
almost a standard bottle episode right here where where suddenly
the ship uh is in a is in a region
where there's just no no wind at all, nothing could
propel them, and everybody just sets around and gets like
superstitious and uh a little bit crazy until the wind
picks back up and saves everybody right. And you can
imagine like if you actually were traveling across the Atlantic

(19:28):
and you didn't know what you were what you were
going to see, or what was going to be out there.
Maybe you'd heard some tales of sea monsters. Who knows,
you get into an area where there is less wind
than you're used to than when you traveled into the area.
You are suddenly be calmed, it becomes hard to travel
and you're just kind of stuck there in the water.
And then you start seeing these weird rafts floating around

(19:48):
in the middle of the ocean towards you. I can
imagine that's pretty odd. Yeah, And in fact we maybe
don't have to imagine, because there are some historical sources
that that may well be referring to this. I guess
it's debatable whether they're referring to this or something else.
But I wanted to look at the question how long
has the Sargasso Sea been written about? Uh. It gets

(20:10):
its current name from Portuguese sailors. I believe of like
you know, the the early modern period, or actually I
think before that, from like the fifteenth century. But but
I was looking around to see how far back written
accounts of the Sargasso c go. And I found an interesting,
possibly applicable bit of history in a book by the
British archaeologist and Oxford professor Sir Barry Cunliffe. Uh. And

(20:35):
the book is called on the Ocean, the Mediterranean and
Atlantic from Prehistory to a d F hundred from Oxford
University Press in and this is in a chapter where
Cunliffe is writing about records of exploration west of the
Pillars of Heracles. So the Pillars of Heracles today are

(20:55):
understood to refer to the Strait of Gibraltar, that gap
between between in Morocco and the Iberian Peninsula, where you
can just go through this narrow passage to get out
of the Mediterranean Sea and into the broad Atlantic Ocean.
And so he's writing about the exploration beyond this point,
out to the west by the ancient cultures of North Africa,

(21:17):
Europe and Central Asia. And for for most of these cultures,
the Mediterranean Sea was of course their bread and butter.
I mean, the sea, even the Mediterranean Sea has has
plenty of dangers and mysteries to it. But sea voyages
within this region where you know, we're well understood for
for trade and and exploration and warfare and fishing and
all that. But sea voyages west into the Atlantic Ocean

(21:40):
or another story. And and so you get plenty of
tales and say Greek thought and Greek mythology about islands
that maybe lay out to the west of of the
Pillars of Hercules, way out there in the ocean that
that is mostly unexplored by your people. Most of the
early explorers who passed west of Gibraltar did so in

(22:01):
order to travel along the coast to the north or south,
so this would be traveling up along the coast of
the Iberian Peninsula uh to form these ports along places
like Cadiz that became a Phoenician port, or south along
the coast of Africa. The Phoenicians and the Greeks did
this to various extents, but the vast and presumably mostly

(22:22):
empty Atlantic Ocean was not not among everybody, but widely
assumed in ancient times to be a place of mystery
and danger, especially by Greek authors. And Kunlift gives the
example of the ancient Greek poet Pindar, who was writing
in the early fifth century b c. E UH and so,
to quote from Kunliffe here describing the pillars of Heracles,

(22:43):
situated at the western extremity of the known world, far
from home, he advises, quote, what lies beyond cannot be
trodden by the wise or the unwise. One cannot cross
from Ghadeer towards the dark west, turn again the sails
towards the dry land end of Europe. The dark West. Yeah,
I mean this vast, stormy ocean. You you don't know

(23:06):
if you know you travel out on it, Like would
would you even reach land if you kept sailing? I mean?
It was not known, however, kind of rites that Phoenician
sailors were more adventurous in general in pushing westward uh
And about around the year six hundred b c E,
a Phoenician expedition sponsored by the pharaoh Necho the second

(23:26):
had been reported to have circumnavigated Africa. And though we
don't have the original sources for the account that I'm
about to describe, there are later Roman quotations of the
accounts of Phoenician sailors possibly pushing further west into the
Atlantic in exploration. And one of these notable sailors was

(23:49):
a Carthaginian navigator named him Ilco that's h I M
I l c O, who lived probably sometime in the
fifth century b c E. The Carthaginians were an ancient
civilization that was based along the coast of North Africa.
I think their their capital was in modern day Tunisia.
But who expanded too much of the ancient Mediterranean? And

(24:12):
then here I'm going to read from Cunliffe as he
introduces and quotes another ancient source for for knowledge about Himilco.
So Himilco quote, whose report published long ago in the
Secret Annals of the Carthaginians, is selectively quoted in a
grossly pretentious poem compiled by our Roman administrator Rufus Festus

(24:33):
Aviennas in the fourth century a d. A few lines
of his Aura maritima will suffice to give the flavor.
And then this quotes lines three seventy four. To the
west of these pillars, Himilco reports that the swell is boundless,
the sea extends widely, the salt water streaks. Fourth no

(24:55):
one has approached these waters. No one has brought his
keel into that sea, because the are no propelling breezes
at sea, and no breath of Heaven's air aids the ship. Hence,
because the mist cloaks the air with a kind of garment,
a cloud always holds the swell and persists throughout the
humid day. And so that's describing possibly some of the

(25:18):
becalmed area of the North Atlantic, with like within the
Gyre region that we talked about before, you know, surrounded
by the currents, but is very often very still in
that middle area that overlaps with the Sargasso Sea. But
then Cunlift goes on to describe further how Aviennas quotes
from Himilco to describe his voyage. Uh Cunlift writes elsewhere

(25:40):
he talks of monsters of the deep and beasts who
swim amid the slow and sluggish crawling ships, and again
great fear of monsters stalks the deep. When the wind falls,
the sluggish liquid of the lazy sea is at a
stand still, while thick seaweed often tops the sea, and
the ti it is hindered by the marshy rack. The

(26:03):
marshy rack oh yeah um and Kunlaf also says Himilko
was evidently not enamored of his encounter with the ocean.
Perhaps perhaps his vessel was drawn south into the dull
drums and reach the Sargasso Sea, as some commentators have suggested,
Or perhaps he reported in this dispiriting way simply to

(26:24):
aggrandize his own achievement and to deter others. Another possibility
is that his original report was embroidered by a Viennas. Uh,
So we don't know exactly what he's describing here, and
if what he's describing is real especially since we're only
getting it quoted by a secondary source and we don't
have the original source. But of course it is true.

(26:44):
There's the danger of the dull drums, the calm part
of the Atlantic, where you won't have winds to propel
your your sales, so you can very well get trapped there.
That could well overlap with large stretches of seaweed, the
Sargassum seaweed that you would find in the Sargasso Sea.
So one possible interpretation of what we're getting here is
that this ancient Carthaginian sailor him Ilco actually sailed to

(27:07):
the Sargasso Sea, survived, returned to Carthage eventually, and you know,
lived to tell the tale. But again it's worth stressing
that modern some modern scholars are are doubtful. It's hard
to know for sure, but some details line up if
they're accurate. You've got these reports about the marshy rack
of seaweed coinciding with the doldrums. It it lines up

(27:28):
in a kind of interesting way. And then finally, of course,
the mention of sea monsters right the I wonder if
it's possible to mistake the shadow of a huge floating
raft of sargassum for a sea monster stalking the deep. Again,
I don't know, but it strikes me as possible. Yeah, yeah,
and well, once you get into discussing sea monsters, of course,
as we've we've explored in the show before, especially looking

(27:50):
at the work of the check ven Douser. Yeah, that's
right on sea monsters. I believe he pointed out in
his book that you know, at times sea monsters are
a manifestation of uh, certainly of of second and third
hand accounts of of actual organisms. Other times their products
of the mind, sometimes their products of of economic or
political forces. So they're a whole host of reasons, uh

(28:14):
to to speak the word of the name of the
sea monster. But that's certainly the yeah, the doldrums that
seemed to be described here, and then the uh, the
the rack, the muck, the seaweed here this does sound
a lot like the descriptions modern descriptions of the sargasso
c oh. And sorry, there's one thing I didn't clarify,
but just to avoid confusion, because it's not a common word,

(28:36):
I had to look this up. Rack here in this
quotation is spelled with the W W R A C
K and I was like, what is that referring to?
Is that like referring to like a like a shipwreck,
because rack sometimes is an alternate spelling of rack or wreckage.
But also I looked it up and apparently it is
also just a word sometimes used to refer to a
massive seaweed like green vegetation. Could be oh, there is

(28:59):
a rack with the W Yeah, okay, well sometimes that
I wasn't familiar with the precise definition, but I totally
understood it in the context of the sentence. It's like,
look at this rack, there's no getting through it. So
so certainly you can imagine that the rack would not
be a great place to find yourself as a human sailor,

(29:19):
certainly in in ancient times. But of course the Iraq
is home to a great many organisms, as we've already
alluded to here. So, uh, for one thing, you have
you have various um micro and macro um epiphytes. These
are organisms that grow on the surface of a plant

(29:41):
and derived derives its moisture and nutrients from the air, rain,
and water. Uh So you have that's those sorts of
organisms growing there. You have fung gi, you have more
than a hundred species of invertebrates that are known to
uh to to live within the sargassum. Over a hundred
species of fish, four species of turtle. Again, and it
kind of spirals out because once you have a certain

(30:01):
amount of of life uh fostered within the sargassum, it's
going to attract other things as well, So you'll see
things like sharks showing up, etcetera. So we are not
going to attempt to cover everything that lives in the sargassum,
but we are going to talk about some of the
standouts because there are some really fun, really interesting, really
weird organisms that call the rack home. And the first

(30:26):
of which I want to talk about is the sargassum fish,
also known as the sargassum frog fish. Now, is this
the one that you lured me into this episode with,
because the first thing that I became aware of when
you were getting interested in sargassum was was that you
came to me and you said, Joe, there is a
fish with hands. Yes, yes, this would be uh, this

(30:47):
would be the sargassum frog fish um and uh and
and I'll and I'll explain what I mean by by hands.
They're not quite hands, but they are enough like hands
that you're committed to get excited um and uh and yeah,
it's probably the most famous sargassum denizen. It's the species
history of history o frog fish of the family uh

(31:10):
at tananara day and it's the only species of its genus.
So uh, we'll describe them here, but also feel free
to look up images or video. I mean, there's nothing
quite like seeing video of these these creatures. I think
there's some wonderful national geographic footage, but also the Weird
House Cinema selection for tomorrow also will feature some actual

(31:31):
footage of this creature right at the top. Um. So
the uh, the sargassum fish grows to around twenty centimeters
in length, so about seven point eight inches. And I
should I guess I should say, first of all, they
generally have this appearance that you'll find with other frog
fish um and uh and and they're related to uh

(31:54):
into the angler fish of the deep. Uh. So they
have these upturned mouths, which kind of give them kind
of this uh, this frowny face look, this kind of
froggy appearance and uh and and so that that's the
first thing to drive home about them. So they have
that that kind of body that I think at number
of you can can imagine, but they sometimes sort of

(32:16):
think of it as the drawbridge jaw. Yes, yes, that's
a good way of describing a drawbridge jaw. And of course,
like like pretty much all fish, you know, they're they're
going to consume by by lunging and inhaling, you know,
pulling their their prey rapidly into their mouth. Um their masters.
These particular fish, though, uh, the sargassum fish are masters

(32:36):
of camouflage, at least within the sargassum environment, because they've
adapted to physically look like the sargassum, complete with fleshy
appendages that look like weed. I've seen some of the
some of the appendages have even been compared to organisms
that live within the weed um. So they just they
just they look like they're just a part of the environment.

(32:58):
You'll see images or even footage sometimes of the sargassum
fish hiding in the seaweed, and you really cannot pick
them out with a human eye. I think at some
point I watched a documentary or part of a documentary
that had some of these in it, and it was
one of those like you know, trick shots where they
show you the shot and then it's like there are
three sargassum fish in the shot, you can't see them

(33:19):
at all, and then has to like circle them or
zoom in on them or something. I think I've seen
the same one. Yeah. Um. But of course it's not
just their physical structure and initial coloration. The other cool
thing about them is they can further adjust their coloration
from dark browns and greens to light browns and greens
to complete the illusion, to to fine tune it so

(33:40):
that they blend in you know, seemingly completely um. And
they can do this quite rapidly as well. This is
important for the sargassum fish because of again it is
a voracious hunter, but also it's the jungle baby, so
you know they're they're also they also have to be
on guard against other predators, so it also helps protect.
Now they let's get to the hands, so if you will,

(34:04):
uh so, theirs their pelvic fins uh, you know the
fins up front. They have nine to eleven rays uh
in them and they're stalked essentially forming what act like clause. Basically,
they can use these things. Again, they look like claws,
they look like fish clause, and they can use these
to grip objects, and they use these to clamber over

(34:27):
and through the seaweed. Okay, so they can use them
to grip objects, not in the sense of like like
our fingers, where you would manipulate objects freely, but they
can grip things in the sense of like sort of
pushing against surfaces. Right. Yeah, they're not gonna be able
to use an iPhone. They can't play the piano worth
of dying. But but they can use these appendages. You

(34:49):
have to sort of grip and push through things, which
is gonna be vitally important when you're hanging out in
the sargassum, like little gravoid spines. Yeah, so they're really cool.
Definitely look up. They're beyond cool. They're a little creepy looking.
I highly recommend checking them out. Um. So, So, obviously
the adults live in the mats and their eggs are

(35:11):
placed there as well, but the larvae developed in the
water columns between fifty and six meters deep. Um. And
you might think, well that, I guess the sargasum environment
then is just no place for for kids, right um.
And this is this is certainly the case, especially since
the sargassum fish is more than happy to eat them
as well, So they're in they're not only incredibly voracious,

(35:32):
but their notorious cannibals. I was reading about some of
the studies where they've they've caught sargassum fish and they've
they've looked inside at their bellies and they'll find like
multiple juveniles. You know, they'll find some juveniles and they
just they'll just just gobble them up delicious. Yeah. So again,
just a fabulous fish. Just it's everything about it is

(35:53):
uh is both beautiful and frightening uh in just the
right proportions. Now, not the only creature that that that
lives there again, and they're not the only creature that
that takes a sargassum as part of its uh you know,
official or unofficial name. For instance, there's the sargassum pipe fish.
This is a species of pipe fish that makes its

(36:13):
home in the sargassum mats uh And like all pipe
fish and seahorses, the male carries the egg. Um. They're
just into these elongated um, you know, beautiful fish with
that kind of signature uh seahorsey head now um. Just briefly,
a couple of other organisms well, first, in general should
say that that the Sargasso Sea in particular is the

(36:33):
spawning site for various eels, uh, including threatened and endangered eels.
But speaking of decapods, there is also worth our consideration
the sargassum swimming crab or U. Portunists say, I uh,
this is uh just one variety of crab you'll find
in sargassum mats, but it's an impressive one and a

(36:55):
species adapted to blend into the environment. They have an
orange brown colorization that apparently matches up with the sargassum
pretty well. And as the name implies, they're more adapted
for swimming than walking. The fourth pair of legs are
modified into paddle like structures. Now, crabs, of of course,
are noted for walking sideways, so you might wonder how

(37:18):
does it swim. Well, they tend to swim sideways as well, uh,
and apparently they're quite fast. They depend on a mix
of active and passive hunting, so they'll they'll actively chase
after something against sideways uh to catch it, but they'll
also fall back on that that sort of ambush hunting
within the jungle of the sargassum. Yeah. Now, in addition

(37:40):
to these organisms that spend all or most of their
lives in the sargassum, there are also organisms that use
sargassom as a sort of like a stepping stone during
their migration patterns. One example that's often referenced would be
young sea turtles. Yeah, and I've also heard that it's
important to even like migratory birds species. Again, it's it's

(38:04):
it's an oasis in the wastes, an oasis in the
desert of the sea. Thank thank thank so. Now, earlier
we we alluded to the sargassum being not not only
this this bountiful environment, but also potentially a problem, a
problem for humans and the sort of human likes and

(38:27):
dislikes concerning beaches, but also just for the environment as
a whole. As the Ocean Foundation points out, it's ecologically
important the sargassum, but it doesn't mean it doesn't have
some downsides, especially when you're dealing with large volumes. Right,
And this is something that's become especially a problem within

(38:48):
just the last decade or so. Actually, it can really
be dated to a year in particular, from what from
everything we've been reading for the year two thousand eleven,
starting around two thousand eleven, something started happening with sargassum
in the Atlantic Ocean, where there was a sudden increase
that has gone on in many years since then, of

(39:10):
of sargassum inundations where beaches and shorelines along areas in
the Caribbean, along the coast of Florida, along places in
the coast of the northern coast of South America would
just be caked with sargassum, like they're just mounds and
mounds of seaweed piling up to the point that it
in some cases would make these shores unusable for what

(39:34):
humans have been using them for, usually in the years beforehand. Yeah,
if if any of you out there are are snorkelers,
or are you know, related to our friends with snorkeling enthusiasts,
then you've you've probably heard about the blight of sargassum,
about the disappointment of of, say, you know, reaching a
popular snorkeling area and finding that there's just sargassum everywhere. Um,

(39:59):
you know. So in in particular, one of the things
that the Ocean Foundation points out is huge rafts of
it can actually smother other sea grasses and even coral reefs. Um.
You know. Granted, coral reefs are facing uh a number
of problems, um you know and are and uh and
we've gone into that in past episodes. But but certainly

(40:20):
this could disrupt your ability to even properly view them
as a as a tourist in the ocean, as a
as a snorkeler, um you know, out there trying to
to observe this natural habitat. Uh. It can also this
is interesting this this has brought up as well. Apparently
sargassum can serve as a means of transport for invasive species.

(40:41):
Though UM, I honestly wonder if this at all compares
to human enabled invasive species transport. It seems like, um
it almost wouldn't matter compared to what humans can and
have done, um you know, importing species like the lion
fish into regions that um that that are not balanced
and off to uh to contain them. Well, yes, but

(41:03):
I would also say that there I think there is
at least a strong likelihood that human behavior is a
major contributor to these these new build ups of sargassum. Yeah,
and we'll and we'll get into into more of that
in just a second. Um, just a few more points
here that the ocean foundation made uh sargassum of course,

(41:23):
can prevent boats and fishermen from setting out to sea.
It can also prevent sea turtles from making it to
nest in these cases as well. So you know, again
you have it massing up on the beach in particular,
if it's um, you know, a certain amount of that
is arguably good for the beach, but if you have
too much of it, yeah, it's going to actually interfere

(41:44):
potentially in a sea turtle's ability to come on shore
lady eggs and then have the hatchlings be able to
properly get back out to sea again in in an
appropriate amount of time. And if it masses on the beach,
the sargassum it, if it's not removed in time, it
can produce hydrogen sulfide, which can have a major can
have major detrimental effects on coastal ecosystems. Yeah, I mean,

(42:07):
it can have all kinds of negative effects on the
wildlife itself. I mean, one would be like if it
doesn't reach the beach, if you're just talking about it
still being in the water, big blooms of algal organisms
in the water can have downstream effects when the blooms
eventually die and then there's all of this dead, decomposing

(42:27):
material in the water, and then the decomposition of that
material ends up robbing the water of dissolved oxygen, which
in turn leads to these big fish die offs and
die offs of other organisms because there's not enough oxygen
in the water for them to breathe. Yeah, and also
all that decomposition in the water can promote harmful blooms
of bacteria and other microbes. I guess the way to

(42:50):
to to think of it is it's basically like spiraling
imbalance in the ecosystem and uh and and it's its
place in this uh this this this cascade of imbalance.
Now to get kind of a I guess, sort of
a bird's eye or I guess satellite view of things. UM.

(43:13):
I found this pretty helpful. I was looking at a
July twenty nineteen article from NASA Goddard. They utilize the
satellite images to observe the Great Atlantic Sargassum belt. Uh
So at this point, based on simulations, they confirmed that
its shape was due to ocean currents and that it
can grow large enough so as to blanket the surface

(43:34):
of the Tropical Atlantic from the west coast of Africa
to the Gulf of Mexico. Major blooms have occurred in
every year between twenty eleven and again, this was a
July articles, so that's as far up as it went
at the time. UH with the exception of which this
was apparently uh in this year was impacted by unusually

(43:57):
low seed populations during the winter, but other wise eleven onward,
it's been sargassum season. Prior to eleven, most of the
free floating sargassum in the ocean was primarily found in
patches around the Gulf of Mexico and the Sargasso Sea.
But then something changed, something seemingly in the biochemistry the ocean. Obviously,

(44:19):
you know, people were asking a lot of questions about
climate change uh and and ultimately I guess the reality
is is complicated, but basically yes, it's pointed out by
a doctor Paula Bontempi of NASA's Ocean Biology and Biogeochemistry Program,
the ocean's biochemistry is changing due to a mix of
natural and human forces, and it seems to be leading

(44:42):
to an ecosystem shift with important implications for marine life
and human life since we depend on many of the
species in question and live in and in many of
the environments that are impacted. UH. Climate change is certainly
a key aspect of this, as it impacts precipitation and
ocean circulation, but increased water temperatures specifically don't seem to

(45:04):
be the cause. It's these other causes. But again, UH,
climate change is very much part of the issue. I
don't want to make it sound like it's not. Yeah,
if you were. If you want to read more in
depth about this research, there's a really good article in
The Atlantic by Ed Young from July nineteen called hy
waves of seaweed have been smothering Caribbean beaches. Again, this

(45:25):
from July nineteen by Ed Young. Uh, that's worth looking up,
and it gets into a lot of the difficulty and
uncertainty and trying to figure out exactly what the underlying
factors leading to this change that we first saw in
the year two thousand eleven was establishing this this huge
belt of sargassum that was not there previously. And and
what we want to be very clear, this Atlantic sargassum

(45:47):
belt is different from the sargassum in the Sargasso Sea.
The Sargasso Sea is further north in the North Atlantic,
off the east coast of of like the United States,
whereas this would be something that stretches more between Brazil
and Africa. In fact, one of the things that ed
Young writes about in this article was the very idea

(46:08):
of the satellite photos that you were talking about that
one of the fortunate things for studying sargassum blooms on
the large scale is that sargassum reflects more infrared light
than the seawater around it, So when you look down
with satellites, sargassum patches can appear as hot spots in
the ocean that can be seen from space. Young sites, Uh,

(46:30):
the researcher named Jim Gower of the Fisheries and Oceans
Canada for for doing this satellite research. But yeah, the
satellite photos found that the bloom really began in April
of two thousand eleven, which correlates with you know these
times when these pile ups on the beaches, the sargassum
inundations really started becoming a problem that people noticed. But

(46:53):
they started noticing the blooms off the coast of Brazil,
and the satellite images from two thousand eleven, and then
Young also points to research by someone named Ming Chi
Wang from the University of South Florida who, along with
her colleagues, they've basically established that, yeah, this bloom is
just going to be an ongoing yearly thing. Now, uh

(47:14):
that that it's coming and it's probably not going to stop. Though.
One of the interesting things this article gets into is
a delay between the proximate causes that are likely leading
to the blooms and then when the blooms show up
within you know, what we can see with our satellites
or what's piling up on our beaches. Because a couple
of the factors that have been identified as likely candidates

(47:37):
leading to these blooms. One is um is water being
discharged from the Amazon River, you know, coming out of
South America. UM. And this water coming out of the
Amazon River is probably being especially saturated with nutrients from
agriculture that's happening all along the US on basin, and

(48:01):
so this is like it's like fertilizer that is flooding
into the ocean and then of course that is feeding
blooms of of this macro algae. And then there are
other factors they get into that are probably contributing, such
as like what the different temperatures are this year. It's
the same thing you were talking about that um that
climate change doesn't seem to be the cause of it
in the sense of increasing ocean temperatures lead to uh,

(48:26):
lead to macro alogy blooms, because that doesn't appear to
be the case, but downstream other effects of climate change
are very likely contributing to this. It's just not the
temperature of the water itself. Another factor that they're talking
about is access to the seed populations of of seaweed.
It's like, how many patches of seaweed are there leftover

(48:48):
that survived the winter of the previous year and can
act as a kind of seed for the regrowth of
the seaweed every new season. Yeah, because I think it
kind of brings back that point of the neumaticis having
a like a year's lifespan, so there's going to be
a certain amount of crossover as well here from one
year to the next. UM. I was impressed one of

(49:09):
the quotes that you pulled from from the Young article
just about how many tons of seaweed we're talking about here? Yeah, yeah, Yeah,
So the estimate I think this would be referring to
the year previous to when this article was written, So
it was published in twenty nineteen, so I think this
would be referring to the summer of eighteen during June,
when the Sargassin Belt was at its most fruitful, it

(49:33):
was estimated to contain twenty two million tons of seaweed.
And then there's even a clarification later in the article
that that estimate is probably low since the resolution of
the satellite camera that's taking the infrared imagery to establish
that number, it has like a minimum sort of pixel

(49:53):
distance resolution, so it can only see patches that show
up at a minimum resolution of something like a kilometer.
I think it was it could be about that, uh,
doing that just stuff memory, but I think that's what
it was. And uh, And so like patches that are
smaller than that, with which there are probably plenty, they're
not even really showing up on the imaging. So that's
a lot of seaweed. That's a lot of seaweed, folks,

(50:14):
And that's a lot, and that's ending up on a
lot of it's ending up on the shores eventually. But
one thing that is worth stressing again is that while
researchers have probably identified some very good candidates for the
explanations of of these blooms and inundations of sargassum in
the last decade or so. There's still some uncertainty. There's
like stuff we don't know about what what could be

(50:36):
leading to it, and what could be the limiting and
contributing factors. Anyway, that the article by ed Young is
a really good read. You should look it up. Yeah, absolutely,
I recommend that one. Now. You know, in the past,
I think it's been brought up when we're dealing with
invasive species or species that are out of balance, one
of the best things that you can do is develop

(50:59):
an appetite for that species. Uh, in human beings. Now,
I don't I don't think anybody's making an argument that
that could um make a difference with the sargassum. But
it is again worth noting that sargassum is something that
humans can eat. Uh. We we mentioned that already, And
I found a wonderful blog titled Eat the Weeds with

(51:21):
Green Dean Um. So his name is Dean, but he's
green Dean, get it and the blogs The blog is
titled Sargassum Sea vegetable, and in this post, Green Dean
points to a few different culinary traditions that have recipes
for sargassum uh, though he points out that given the
different species, basically it's sargassum is going to quote very

(51:43):
in taste and texture, so there is no one way
to cook your local species uh. He says that some
amount of experimentation is going to be required, but basically
he goes through different cuisines. In this post, points out
that sometimes it's consumed fresh, other time it's cooked, saying
coconut milk or vinegar or lemon juice. Other times it's

(52:04):
smoke dried, or it's boiled. Sometimes it's even sweetened and
put into steam buns. Sometimes it's cooked with fish. Basically,
they're just numerous ways to approach it, but it's it's
worth checking out the link. I recommend it. It said
eat the weeds dot com. You'll find a post on
the sargasm sea vegetable um. I'm not sure I've ever

(52:25):
had sargassum in a dish. Maybe I have and I
just wasn't alert to it, But now I feel like
I really, I really want to have it. I don't
know if I have either. I mean, I've had a
number of seaweed salads, but I don't know what species
were in them. Yeah, well, I know some basic things.
I mean, I know like combo, and combo of course,
is a seaweed based food additive that is an amazing

(52:46):
source of umami flavor. It's it's it's almost like raw
msg it's it's good stuff um but but yeah, other
than that, I don't know. I mean, I've had I've
had like various seaweed salads at Japanese restaurants that have
had different types of seaweeds, some that looked kind of
like orange brown, like like some species of sargassum do
So maybe I have I don't know. Huh, Yeah, I

(53:08):
think I've I've only I know of at least one time,
had like a sampler of seaweed salads from the Japanese restaurant.
But in those cases, I think they were all still
rather green. They didn't have um any kind of darker coloration.
So I don't know. I'm gonna look for it now
now it is on it is it is something I
want to specifically try out, knowing that it is sargassum.

(53:30):
I just looked it up to make sure I I
thought that combu was not sargassum, and it is not.
Combu is a type of kelp. Well, obviously we'd love
to hear from everyone out there about this topic in general,
but but specifically on this question of the cooking and
the consumption of sargassum. If you've, if you've, you definitely
know you've had it, and you've had in a particular

(53:50):
way that was yummy or or or or not yummy.
Let us know we would love to hear from you,
and likewise, just in you know, in general, any feedback
about about the various organisms we've discussed here surrounding sargassum
or uh sargassum, seaweed itself. Perhaps you're a snorkeler and
have your you know, two cents you want to throw
in right in, we'd like to hear from you. In

(54:13):
the meantime, if you would like to hear other episodes
of Stuff to Blow your Mind, you can find us
in the Stuff to Blow your Mind podcast feed and
you know where to find that, just wherever you get podcasts.
Um subscribe if you can rate us, if the platform
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(54:34):
thankful if you're if you're listening to the show, and
uh you know, right in, let us know what you
like about the show, what what you would like to
hear from us in the future, what other topics you
would like us to consider. Yes, absolutely, uh so, I
guess we're closing out here, so huge thanks as always
to our wonderful audio producer Seth Nicholas Johnson. If you
would like to get in touch with us as as

(54:56):
Rob just asked there, to let us know feedback on
this episode or any to suggest a topic for a
future episode, or just to say hi, you can email
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(55:18):
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