-: Good evening.
We're pleased to have you join us
for our annual Seaside Chat Speaker Series,
about ocean topics associated
with Flower Garden Banks National Marine Sanctuary,
and the Gulf of Mexico.
This year we are also part
of the National Marine Sanctuaries Webinar Series,
hosted by NOAA's Office of National Marine Sanctuaries,
as well as the OneNOAA Science Seminar Series.
During the presentation,
all attendees will be in listen-only mode.
You are welcome to type questions for the presenter
into the questions box,
in the bottom of the control panel,
on the right-hand side of your screen.
This is the same area you can let us know
about any technical issues you may be having.
We will be monitoring incoming questions
and technical issues,
and will respond to them, as soon as we can.
We are recording this session,
and we'll post the recording
to the National Marine Sanctuaries
and Flower Garden Banks National Marine Sanctuary websites.
We will notify registered participants via email
when these recordings are available.
And in the handouts pane of the control panel,
we have provided a PDF of a 2019 paper,
on the importance of rhodoliths.
Suzanne Fredericq is the primary author,
and Emma Hickerson, Research Coordinator
at Flower Garden Banks National Marine Sanctuary,
is a co-author on that paper.
I am Kelly Drinnen, Outreach Specialist
with Flower Garden Banks National Marine Sanctuary,
and I'll be facilitating today's webinar,
from Dickinson, Texas.
With me this evening, is Leslie Whaylen Clift,
our Constituency Affairs Coordinator,
who is joining us from Galveston, Texas.
Leslie will be helping me
with backend administration of this webinar.
NOAA manages a system of marine protected areas,
called National Marine Sanctuaries,
that are found throughout the coastal United States.
National marine sanctuaries are special ocean areas,
set aside by Congress, to protect for future generations.
They're like national parks and national forests,
but underwater.
The National Marine Sanctuary System
consists of 15 marine protected areas,
that encompass more than 600,000 square miles
of marine and Great Lakes waters,
from Washington state to the Florida Keys,
and from Lake Huron to American Samoa.
The system includes 14 national marine sanctuaries,
and the Papahānaumokuākea and Rose Atoll
Marine National Monuments.
The NOAA Office of National Marine Sanctuaries
is mandated to conduct research, monitoring,
and resource protection, education, outreach,
and of course, management of America's underwater treasures,
to preserve them for future generations.
National Marine Sanctuaries are also living classrooms,
where people can see, touch, and learn,
about the nation's Great Lakes and ocean treasures.
Today's Seaside Chat Series is hosted by
Flower Garden Banks National Marine Sanctuary,
the only national marine sanctuary in the Gulf of Mexico.
This sanctuary consists of three banks,
or small underwater mountains,
that are home to some of the healthiest coral reefs
in the world,
an amazing algal-sponge community,
and deep reef habitats,
featuring an abundance of black coral.
In January of this year,
the sanctuary also published a final rule for expansion,
which will add portions of another 14 reefs
and banks to the sanctuary.
In the process of exploring
additional banks in the Northwestern Gulf of Mexico,
researchers have repeatedly encountered
pockets of algal nodule habitat in the deeper reef areas.
In addition, during a live broadcast expedition, in 2019,
scientists encountered a relatively large reef area,
covered in crustose coralline algae, that you see here.
Extensive sampling of these macro algae
has resulted in an innovative approach
to exploratory research for the discovery, identification,
and classification of algal diversity.
In addition, research into the importance of algal nodules
in the lifecycle of algae,
has revolutionized preconceived ideas
about the ecological importance
of this unexplored ecosystem.
Today, we welcome Suzanne Fredericq, Professor of Biology,
at University of Louisiana at Lafayette,
to talk about these remarkable algae,
and what she's been learning about them.
Suzanne Fredericq received a bachelor's degree in zoology
from the University of Ghent, Belgium, in 1980.
A master's degree from George Mason University,
with research done at National Museum of Natural History,
at the Smithsonian Institution, in biology, in 1984,
and a PhD in botany,
from the University of North Carolina,
at Chapel Hill, in 1988.
She then did eight years of postdoctoral work,
at the National Museum of Natural History, Smithsonian,
University of North Carolina at Chapel Hill,
and Duke University,
before joining the faculty at the University of Louisiana,
at Lafayette, in 1996,
where she is now a professor of biology.
She has a passion for the biodiversity
of marine red algae, worldwide,
and is here tonight, to present to you all.
Welcome, Suzanne.
And I'm handing the presentation over to you-
-: Yeah. Can you hear me?
-: I can hear you now, yes, thank you.
-: Yeah, what-
thank you so much... -: Oh, I can see
your presentation, and we see you,
you're ready to go.
-: Very, thank you.
So thank you so much, Kelly,
for inviting me to talk, this evening,
about the remarkable algae of Flower Garden Banks.
I will focus on the marine macroalgae,
also called seaweeds
and some of which you see here, on these slides.
And I'm gonna put emphasis on the algal nodules,
because they're so important in the ecosystem
of the Flower Garden Banks.
Our research group is here,
located at University of Louisiana, in Lafayette,
and since 1998,
we have been conducting collection surveys of seaweeds
on the hard banks of pinnacles on the continental shelf,
offshore Louisiana and Texas.
And the habitats we typically collect algae in,
are called mesophotic habitats
and they are deeper than 40 meters depth,
and mesophotic means middle light habitats,
because light doesn't, of course, go very deep,
not more than 100 meters.
So, for algae to grow and photosynthesize,
they of course, need the light.
So, below that zone, where the photosynthesis cannot go on,
you're not gonna find the algae.
So this is, of course, is in contrast with a lot of animals,
who can live much deeper in the Flower Gardens
and everywhere else.
So the mesophotic coral ecosystems,
as is the Flower Garden Banks,
they are really remarkable habitats,
and they are very hot right now,
because there are a lot of books
that have been describing the different habitats worldwide,
a lot of papers have been written.
So it's all very interesting.
And before starting,
I would very much like to start with the acknowledgments,
right off the bat.
I thank the National Science Foundation
for our work on those rhodoliths.
Where's my-
It doesn't-
On the rhodoliths, what you see here.
I think it might be here (mumbling)
And then also,
very much, would like to thank Jason White,
and Eric Glidden,
who were wonderful in handling the collection
of those nodules, and all the algae,
using the ROV, aboard the R/V Manta,
which is the research vessel of the Flower Garden Banks.
Of course, we would like to thank, Emma Hickerson,
G.P. Schmahl, Marissa Nuttall,
because they are so interested in the algae too,
in the coralline algae,
and have been extremely supportive of our research.
And I also want to thank Kelly Drinnen, again,
for inviting me to talk.
Then, there's a whole group of phycologists,
those are people who study the algae at the university,
and you see most of those names here are my collaborators.
They are all the names, here of former PhD students,
and we still continue to collaborate very much.
So several of them are still here at university,
with, being in instructor positions, etc.
The main point I would like to make
is that when after you've seen this presentation,
that you become more aware
of the enormous contribution of the algae,
in both the East and West Flower Garden Banks,
and especially of the algal nodules, what you see here.
My, I don't know why my,
yeah, here, yeah.
All the nodules what you see here,
this little circular, kind of little stones,
and a lot of pink,
because-
but some can have different colors too.
They have some green, browns, orange, etc.
And those pink nodules are actually
formed predominantly by a group of red algae,
that are calcified and are called coralline algae.
So those are red algae that are calcified,
and some of those form those little nodules,
and others are just crystals, coralline.
So, those we will seek are really at the basis
of the health of the ecosystem,
in the Flower Garden Banks.
We can see that there's a lot of other,
black corals and such,
they are all attached to those nodules, a lot of them.
We have sponges and, for example also here,
that big barrel sponge that's been spawning.
Everywhere you see, there is competition for space,
and what's good space is the fact
that those nodules are hard substrata,
so it's very easy for benthic organisms
which live at the bottom, to attach to them.
So, we can see there's a great diversity,
maybe in this slide, there are 20 different species,
of those rhodoliths.
And when we go a little deeper, we see that,
those little rhodoliths or those little algal nodules,
I should call them, basically are replaced by,
those, more platforms, consolidated substrata.
But we see that amongst the corals
and so, all of that pink is also crustose coralline algae.
So, we see crustose coralline algae,
as really encrusting all free-living algae nodules,
and we see it's all over the place,
below the hermatypic coral zones.
So the big balls of corals that we see,
that get there close to 15 meters.
No, 15 or 20 meters from the surface,
below that coral zone, the hermatypic coral zone,
we see all those rhodoliths.
So it's very important.
And you might ask,
why study those deepwater mesophotic macroalgae,
in the Flower Garden Banks?
We can see this,
but you see, why do we have that diversity?
And, for many people, they all look the same.
All that thing could be the same,
but in fact, they consist of all different species,
from different genera, different families, etc.
And I'm gonna put the emphasis on the algal nodules,
or the rhodoliths, and the name says it,
rho-do-lith, the red stone.
And because they're all, they're unattached,
we can call them the rolling stones.
So they are very important substrata,
hard substrata, and they also consolidate substrata.
And those rhodoliths, or those algal nodules,
are crucial components of the photosynthetic community,
that produces oxygen,
and also provides food to a whole suite of herbivores,
like herbivorous fish or molluscs,
and they also provide canopy and shelter,
for invertebrates and vertebrates.
So they're very important in the ecosystem.
So, they also, those rhodoliths or algal nodules,
also contribute to major ecosystem functions,
such as carbon cycling,
and they form structurally complex habitat frameworks,
all of which are rhodoliths together,
that associates with high biodiversity.
I've been to a lot of places, all over the world,
but I never seen the amount of biodiversity
of those algal nodules that we find
in the Flower Garden Banks
and in the other hard banks in the northwest
Gulf of Mexico, it's really extraordinary.
So, it's also very important,
because we talk about the Flower Gardens,
the coral reefs,
that coral larval settlement
is chemically mediated by the coralline algae,
which are composed of high biogenic calcite,
that is very sensitive to decreases in ocean pH.
So there is the calcite,
this coralline algae, likes to calcify,
the major crowd consists of calcite,
and those are the only algae that produce,
actually, calcite.
Most of the calcium carbonate
is found in the other polymorph, aragonite.
But we see, that in some of those calcium rhodoliths,
we have both.
So, the fact that they are so sensitive,
the calcite's sensitive to decreases in ocean pH,
those corallines and those rhodoliths,
may be the first indicators of ocean acidification.
By having calcium carbonate, this dissolve,
and the solution of calcium carbonate,
with, of course, resulting negative effects,
on a variety of biotic interactions,
and because all those calcified organisms
will probably not be able to withstand much,
too much of the ocean acidification.
But, I have to say,
they are extremely difficult to identify, taxonomically.
It's much easier to identify the fleshy algae,
but those little corallines are extremely difficult,
because so many look the same from the outside.
But like with all the macroalgae,
it's the inside of the organisms that we like to look at.
So what we want to work up, in the Flower Garden Banks,
what we have begun, is studying the biodiversity,
the taxonomy and systematics,
and those other evolutionary relationships,
of all those corallines,
and we have described a lot of species,
also the biogeography.
So one of those particular species
that we find in the Flower Garden,
whether they relate to, in other parts of the world,
and the Gulf of Mexico.
So it's very interesting,
and it really is all-encompassing, basically.
So the Flower Garden Banks,
they're all hard banks,
and they are found on the top of salt domes,
but what's very interesting,
is that all throughout the northwestern Gulf here,
we have different hard banks,
but it's only in the East and the West Flower Gardens,
that those salt domes are basically topped by corals.
All the others are mostly topped by those rhodoliths.
And, but it's also very interesting,
it's that they are found, those hard banks,
all of those, in offshore here, in Louisiana,
in the vicinity of areas
of intensive oil and gas exploration.
Those banks surmount salt dome slopes,
where the strata trap the hydrocarbons.
And that's where,
that's why they're always in the vicinity
of the oil and gas exploration.
The salt domes are nearly 100% pure salt,
with tiny fractions of calcium sulfate.
And, if underground water dissolved the salt away,
the remaining calcium sulfate
forms a somewhat insoluble barrier,
that is then acted upon
by anaerobic sulfate-reducing bacteria,
which then convert the calcium sulfate,
to calcium carbonate, which is calcium carbonate,
and there is such an enormous amount
of calcium carbonate in those hard banks,
all over the northwestern Gulf,
because it started,
a lot from the conversion of calcium sulfate.
So, the bacteria obtain the carbon necessary
to reduce the calcium sulfate to limestone,
which is calcium carbonate,
from those petroleum hydrocarbons,
that accumulate in pockets along the salt dome banks,
and the edge.
And it is in the banks' caprock slopes and peaks,
that are then covered by those free-living, unattached,
benthic algal nodules.
That's what we see here,
and that are, then also called rhodoliths,
'cause they're red stone.
And, we see that those rhodoliths
are predominantly accreted by crustose corallines.
Which are also called the CCA, crustose coralline algae,
that precipitate calcium carbonate
in their organic cell walls.
So the whole area is already saturated
with calcium carbonate,
and on top of that, you have all those calcified algae,
the coralline algae.
So it's a very rich area for calcified algae,
And common in the rhodolith beds,
because you have those individual rhodoliths,
and then they form big aggregations,
called rhodolith bed or the aragonite nodule beds.
We found them both in the West and East Flower Gardens,
below the zone of the hermatypic corals,
and what we've seen,
is that most of the very interesting depths,
are at 50 to 80 meters depth.
And that's where we see all those wonderful nodules,
and you can see, there is some are green,
because some of those nodules
are gonna be covered by green algae,
by spongy green algae, by coralline algae,
by all the types of red algae, etc.
Very diverse, and it's probably here
to 10 different species in that little site.
So it's very interesting,
and we see that often,
they're interspersed with a little bit of sand,
but mostly, once you get into those rhodolith beds,
basically they dominate the bottom,
and they are so important in the hard substratum,
because a lot of animals need to attach to hard substratum.
And there they are, those rhodoliths to attach to.
And here is a shot, this is really wonderful,
where we see the big, large, fleshy algae,
and also intermingled with all those other little nodules,
because they attach to those nodules.
Then we have also brown algae, we've got green algae,
it's extremely diverse.
And here too, we have, when we want,
when we see an alga we want,
there is the manipulator arm of the ROV
focuses on a particular alga
and then sucks it out and put it into a basket.
And then we can, once it comes on board ship,
we can then take it and work from there.
But you see here, right away,
you can see that there is a little nodule,
this is a coralline alga,
and on top, is a completely different crustose alga,
but that has nothing to do with corallines.
So there is a lot of mixtures going on.
Because there's so much competition for space,
once there is a nodule,
everyone is gonna wanna, basically settle on it.
And here we see a lot of nice green ones,
but everything is full of those nodules, those rhodoliths.
And we see that also, with the rhodoliths,
we have a whole bunch of fleshy algae,
wonderful greens and here too,
they are lowered then in the basket.
A great big variety.
Seems a little rhodolith here, it's a coralline,
and on top, it's a green alga,
and then on top of that,
you have more fleshy algae.
So it's really a very dynamic system,
and they can roll.
So sometimes, they roll if there is enough current there,
and then of course it flips,
and then it continues to grow upside down.
They're very dynamic.
And this is here the first poll question.
Kelly?
Kelly: Okay, yes. We have a poll question for everyone.
We wanna see if you've been paying attention.
We wanna hear the answer,
What are mesophotic habitats?
Are they deepwater, light-dependent ecosystems,
deepwater, light-independent ecosystems,
shallow, light-dependent ecosystems
or shallow, light-independent ecosystems?
So, go ahead and make your selections.
We'll give you about 30 more seconds.
About half of the people have responded at this point.
Suzanne, they're definitely favoring one answer
over the rest.
-: Okay.
Kelly: We'll let you know what that is, in just a minute.
Yeah, they're, it sounds like they've been listening.
(Suzanne chuckling)
Okay, we're up to 70% voting,
we'll give it another 10 seconds, or so.
Get your votes in now.
What are mesophotic habitats?
Alright, we're gonna close the poll now,
and share the results,
and it looks like 54% of the people responded
that these are deepwater, light-dependent ecosystems.
And we're back to you, Suzanne.
-: Okay, so, we continue then.
So, once we get all those nodules,
you see here, for example,
you can see that they're all attached,
the fleshy algae are attached to the nodules, etc.
And a lot of those algae are completely new for the Gulf.
They are absolutely extraordinary.
There are some gelatinous ones,
there are hard ones and they all grow together.
So, and these are all the rhodoliths,
and those are probably here,
six different species of rhodoliths.
You might think they all the same,
they are not.
And then, we bring those, live, to the lab,
and then we have it to further study.
It's really fantastic.
And there are actually two,
we found that there are two major categories of rhodoliths,
of those algal nodules.
One, that are biogenic in origin,
and those are formed
by the crustose coralline algae themselves,
so, basically, it's everything that you see,
in those little nodules,
are formed by the crustose corallines.
And you see, here too, those are different species,
and those are, with all those knobs and stuff,
those are, typically, biogenic ones.
And Joe Richards, who's was a former student of me,
and who's now here at post-doc,
his specialty is corallines,
and he, basically he took one of those little spines,
and cut them open with a razor blade,
and then opened it up,
and you see that this here,
with the scanning electron microscope,
you see there are all those little cells,
and surrounding those cells,
it's all gray, and so, well,
that's all the calcium carbonate in the form of calcite.
And then you see, interspersed, those openings,
which were the basic, the conceptacles,
the fruiting bodies of that species.
But here we have, what is very interesting,
we have another polymorph of calcium carbonate,
called aragonite.
So we have here the main...
Calcium carbonate is the calcite,
and inside those empty conceptacles,
or fruiting structures, we have aragonite.
So, it's very interesting.
And that's a typical biogenic rhodolith
and they belong in the three orders of the coralline algae.
We find them in both the three orders.
And then we have the other group,
which are called the autogenic rhodoliths,
and they are rhodoliths with a non-coralline core.
So it's different from the biogenic rhodoliths,
which are formed by the corallines themselves.
And the autogenic ones, it's different,
it's a piece of rubble,
a piece of calcium carbonate rubble,
that become secondarily,
basically settled by either green or corallines,
or little animals
or other crustose algae.
So that's different, so that was-
so that then became calcium carbonate,
and that then gets settled.
And we see here that we-
so whenever we see greens,
and so those are gonna be green algae,
those are gonna be,
they are growing on autogenic rhodoliths.
We have here too brown ones,
but you see some of those with those little spikes,
those are gonna be the biogenic rhodoliths.
And there is a great variety
of those biogenic and autogenic rhodoliths.
You see those spikes?
Those are the biogenic ones,
and the others,
are gonna be the autogenic ones.
And you see, they completely grow together,
in those rhodolith beds,
so, that's a biogenic one and along other algae.
This is a little Halimeda,
it's a green alga that also produce calcium carbonate,
in aragonite form and then once it breaks off,
it can contribute to calcareous sand.
So everything is very dynamic,
in those fantastic, kind of, mesophotic habitats.
So, after we were,
we could go to the Flower Gardens,
we were able to collect an alga here,
that turned out to be Mesophyllum erubescens.
And that's so interesting
because that species was never found
in the northwestern Gulf.
It is found in Brazil
especially in all the banks in the northwestern Gulf
but we had not,
we had not no material in the Flower Gardens,
and here it is, here it shows with SEM
how the reproductive structures are situated where they are
and how the plant basically grows.
And what is so interesting
is the fact that we have those salt domes,
and when we look in Brazil,
so, there too, you have those salt domes,
and a lot of the oil explorations.
While there is a lot of similarities
between the algae we find in those rhodolite beds in Brazil
and in those of the northwestern Gulf,
because there's all that sulfate,
which then converts into calcium carbonate.
And there, we find the greatest, in those two areas,
the greatest diversity in rhodolith.
Very different from what we find in the coast of Ireland
or the coast of Brittany, in France,
or the Mediterranean.
We don't see that great diversity as we see here.
So, we've talked,
and we wrote a little paper
about the range extension of that species,
with the first times found in the sanctuary.
And also, we continue, you can see,
so you would think those are all the same things,
no, they're all different,
because when we do the sequencing,
the DNA sequencing of it,
we found that there were three different species
that we found in the northwestern Gulf,
and that was the first time too,
that that genus was found in the Gulf, as a whole.
So we see it, it's like the Red Sea,
we have the New Zealand,
but it was never described,
or it was never reported from the Gulf
and we have that three,
we described that three new species.
Really fascinating for the diversity
as it is tremendous.
And then we're also interested in describing of new species
and this is one that is close to the heart
of Emma Hickerson,
and she alerted us to that.
And it is indeed, absolutely extraordinary.
It's, they are not rhodoliths,
they are not, they are coralline algae,
but they are not rhodoliths, they are not nodules,
they are not appressed to a hard substratum,
but in fact, what you see here,
is they are very flaky and fragile,
and when you look underneath that area here,
the living parts of the alga,
you see here, you can see,
that those are the older part of that alga.
So basically it dies out and up above it,
you get the new alga growing.
It's really very special, we think.
And because of that, we are naming it after Emma Hickerson,
as a new species,
of a genus that was never reported in the Gulf.
So we see here for example,
this is the upper part of some of those little blades here,
these little dots are the reproductive structures
and this is the underside,
you can see it's already white,
but then on top of it,
you get those new layers being formed,
and that's, that often forms a depth
of those algal platforms.
Very interesting.
And here we see how they actually
are attaching to the bottom.
So this is that species we're calling after, Emma.
But then we have, we found other species in the same genus,
which are also new, we still have to describe,
and you see it's a little bit more rigid,
it's not as flaky as the other one.
And when we look at where they all come out,
we see that there are six species that we found,
of that Crustaphytum in the Gulf
and they all are distinct species,
in addition to the one from, we named after Emma.
So what we see here is Joe Richards,
who has sequenced all of those species from the Gulf,
those are just Gulf species,
and we see there's a whole bunch of new one,
a spinoff that are being, that's the right bit,
but that's all in press now,
and this is only from the Gulf of Mexico,
including the Flower Gardens
and then other parts of the Gulf.
And what we see is that there are like here,
over 20 species completely, species that we have
recognized and characterized,
instead of maybe the four or five that were shown,
that were listed before in the Gulf,
so it's really an explosion of diversity,
that we are looking at
and it's probably another 30 or 40 new species
that are waiting to be described.
It's absolutely extraordinary,
that great biodiversity of those coralline algae.
And also when we were,
when I was invited by Emma and Marissa to be on the trip,
it was for deep water survey,
but I saw those little mounds there.
And, Tom...
(pages rustling)
Yeah, Tom Bright, I'm sorry, mentioned
that this was all built those mounds,
by little fish, little sand tilefish.
And he builds a little dome and then lives inside
and attracts females, etc.
And we saw them, it's absolutely extraordinary,
'cause I didn't know what those were,
and he mentioned it.
And you see there too, those mounds are so diverse,
all different parts of the corallines and all the algae,
and every time you see those, I forgot to say,
those laser points that means it's,
this is of 10 centimeters.
So we see the rest is kind of flat
and suddenly we have those little mounds
that were built by that little fish.
So they are really ecosystem engineers,
then we can say
and it's like beautiful cathedrals (chuckling),
and basically nothing.
And also, what we found is that those rhodoliths
are often very closely associated with other invertebrates,
for example, as soon as we saw that big conch
and as soon as we came close,
we saw first that there was an octopus,
who was there resting in a little ledge inside.
And as soon as we came close,
he came out of it's little rhodolith bed, as we can see.
And you could see on those tentacles,
there were actually some of those rhodoliths attached to it.
And, we don't know exactly what he was doing,
but it's like he was
because a lot of algae grew on those rhodoliths,
and there were a lot of herbivorous fish,
it seemed and so perhaps he's attracting them,
and just waiting to catch it.
So it's all very interesting.
We don't know all the answers of course,
but as soon as we came close up,
he moved out of that hiding place,
and then right on top of those little rhodoliths
and the conch.
So this is very interesting,
and probably some people may know better what it means.
But we see here too, you see all those coralline algae,
green algae and this is most consolidated platforms,
and at the bottom, you have the rhodoliths.
And you see, full and full of algae diversity.
So now we are at another poll question.
Kelly: Yes, we are.
You all did so good on the first one,
the majority of you got the right answer,
let's see how you do on this next one.
What are rhodoliths?
Are they biogenic algal nodules, autogenic algal nodules,
important ecosystem engineers, or all of the above?
Let's see how closely you've been paying attention.
Well, it looks like there's a-
and Suzanne, there's a whole bunch
who're heading for one direction,
but other few answers out, on others,
so let's see how we do overall.
We'll give it about another 20, 30 seconds.
We're up to 70% voting right now.
Keep on voting folks.
Do you think it's biogenic algal nodules,
autogenic algal nodules, important ecosystem engineers,
or all of the above?
About five more seconds,
and then we'll close the poll.
And the results are in.
88% responded "all of the above",
and that would make you correct.
Suzanne has covered all of those topics,
and the answer is all of the above.
-: Yeah.
Kelly: Alright. Back to you, Suzanne.
-: Okay (chuckling)
So what we see here is that,
in addition to those rhodoliths,
those non-attached nodules and coralline algae,
we can see that there's also-
those coralline algae also can consolidate substrata,
hard substrata in areas that were a little bit deeper,
we found then the rhodolith zone.
And here you can just see here, this little area,
it is, here is-
oh no, where's my-
Yeah.
You can see, that it's a...
I'm looking for my...
I cannot find my...
Kelly: Right now your cursor's on the top right photo.
-: It's, I don't see it,
but anyway, that's where I want, top right.
You see there are pinks, those are one,
that's one species of coralline,
another one is another species of coralline,
the bright red, it's not a coralline,
but it's a crustose algae,
in the Peyssonneliacae.
We have a whole bunch of pinks.
All different species, all competing for space
and often growing on top of one another.
And we see here too, underneath,
we see those are all Peyssonneliacae
on those major platforms that we see.
And they also keep all that hard substratum together,
as compacted, so that the algae grow
basically from one alga to the next one.
And so they all cover that hard substratum
and become part of the hard substratum.
And here we see too, we have a lot of little ledges etc.
And then you see a hole with a fish
and so that were hiding in there underneath.
And all around it, you see again, those fleshy algae,
and those coralline algae and crustose algae.
So everywhere you go it's a bit different
and that makes it so fascinating,
because there's one algae here,
were not found in certain areas, in the Flower Gardens
but here they are.
So every spot we see, is so rich in algae
and they're all so different.
I like what we see here too,
some consolidated outcroppings where we have corallines,
we have Peyssonneliacae, all the crustose algae, etc.
And here, too, those outcroppings,
and you see at the bases here,
we have those rhodoliths, those nodules,
and here we can see again, we have some nodules,
those are the autogenic ones,
and here are some probably, a biogenic one.
And we see that on the autogenic one,
we have in this case, a coralline,
it's gonna grow over it's little nodule,
and basically attach to another nodule next.
And so little by little, we see that they become attached,
and form, become part of the consolidated,
kind of substratum.
So it's very interesting.
And then you see here on top,
you have the little green nodules,
and other green, all growing on top of one another.
It's really fascinating.
And then you're gonna have the little fish,
who prefer this little alga to eat,
herbivorous fish and then another one here.
And so everything is, looks very healthy,
and that's just feeds a lot of that entire ecosystem.
So, when did we become actually aware
of the importance of the rhodoliths, of those nodules,
for the biodiversity in the northwestern Gulf of Mexico,
the mesophotic habitats, and also for alga ecology?
So because it happened after April 20, 2010,
when the BP/Deepwater Horizon oil spill
spilled over 200 million gallons of crude oils
in the vicinity of our research sites,
and this is where there was the,
it blow up the Deepwater Horizon,
that was second bank, this was one of our area,
another one was Ewing Bank,
and this was very badly impacted by the oil spill.
Because Ewing Bank, which before the oil spill
was so diversity-rich for rhodoliths and other species,
looked like a graveyard,
when we first revisited the site in December 2010.
You can see,
while all those rhodoliths were teaming with life,
pre-oil, it looked very healthy,
now they look dead, were bleached, and bare.
And, it's-
so that's all we found,
so we brought them to the lab, just to get something back,
and we put those kind of, dead looking rubble,
in the lab, in microcosms and water
that was collected from the same area
we got those nodules from.
And then what happened after a couple of weeks,
we would see, like we see here,
that some of those dead-looking rhodoliths,
suddenly became, again completely covered by algae,
that looked exactly the same as that was in the-
that was appearing in the Gulf before the oil spill.
So that would then be an autogenic rhodolith and those two.
So we say how is that possible,
all those things we did not see in the field,
but they all grew out of those surface
of those dead-looking rhodoliths.
So that's where I became so interested in that
because before that oil spill,
none of the people in our lab
were interested in crustose corallines,
but afterwards, we saw, my gosh, it's so interesting,
and we really concentrated a lot of efforts
in understanding them.
So, Thomas Sauvage, who was also
a former grad student,
what he did, he did environmental sequencing
inside those rhodoliths, autogenic rhodoliths,
and he recovered a great diversity of photosynthetic taxa,
in the interior of, in this case, six autogenic rhodoliths,
as well as from the other calcareous substrata.
And what he found is that you see all of that
it was teeming with, basically,
finding of diversity of a whole bunch
of macroalgae and also micro, small, and the big ones.
So that's what made us think that those rhodoliths
even do they looked dead,
were actually marine biodiversity hotspots
that may function as seed bank,
for the diversity of those algae,
because they were not there in the field,
we bring them home
and suddenly we get all those algae
and photosynthetic algae in our tanks.
And then, that was for the autogenic algae
and then the biogenic one,
those are the one
with all those weird little spines, tubercles.
There too, we found the same thing,
that there was plenty of life inside the cells
of this biogenic one you see here.
Those are the cells' interior, that's all calcite,
calcium carbonate, and they just...
Sherry Krayesky, was also a former PhD student,
she found all those weird things,
inside those biogenic ones,
so the autogenic one should bring diversity,
because, of course, you can have all those,
in all those crevices.
And so within that autogenic rhodolith,
you can find a whole bunch of things,
within the biogenic ones they can only grow,
we get structures where only in the cells itself
of the coralline.
And so we found those after the oil spill.
So there too, we said that the interior
of those biogenic rhodoliths,
are also marine diversity hotspots,
that, perhaps, may function as resting stage,
as it was for microalgae.
These are those.
And in order to confirm that,
Sherry Seif, was able to pull out
some of those weird stages
and was able to link them,
in with mature, basically type of dinoflagellate algae,
called Prorocentrum, that were swimming in the aquarium.
So, based on DNA sequences,
she could show that actually those weird stages
that we see here,
were actually part of the life stage of dinoflagellate,
in particular the Prorocentrum,
because you see the DNA was exactly the same.
So those lived in calcium carbonate-lined cells
so those are the hard, we call them the endolithic stage.
Lithic is like a stone inside, that we see here.
And we were able to link those stages inside,
with the free-living stages.
So that was really, very exciting.
And then to confirm even further,
she picked those weird stages,
and did TM on it and you can see it's very young,
because they don't have a real cell wall yet and so...
But it has a lot in common with the TM shots,
where the structure is not those dinoflagellates.
So this is really nice,
that we could see that there are those microalgal stages
that nobody knew about,
that are found in those rhodoliths.
And then she looked more and more
in different types of biogenic rhodoliths
and everywhere, we see different kind of stages.
So a lot of them, we haven't been able to link yet
with a certain microalgal stage
but that's all gonna happen.
So, we have another polling question.
Kelly: Yes, we do.
And here we go, folks.
The interiors of rhodoliths can be important
diversity- rich ecosystems, as are their exteriors.
True, or false?
Oh, there's a definite leaning on this one, also, Suzanne,
we've got some good votes coming in.
-: Okay.
Kelly: Good votes.
We're about halfway there.
Keep voting, folks.
Oh, I can tell you all have been paying attention.
They've been listening, Suzanne, they really have.
We're gonna go ahead and close the poll
and 99% think that is a true response.
And I would say they're correct.
Right, Suzanne?
-: Absolutely. Yeah.
So each of those rhodoliths
is actually an ecosystem by itself
and then at the individual level, the individual rhodolith.
And then we have all those rhodolith beds
and so on the big level, we have another ecosystem.
That's why it's so interesting
and we were not aware of it,
we only became aware of it because of that oil spill.
So, and now we find them so interesting
probably the most exciting algae
in the whole northwestern Gulf.
So what did we learn,
is that that environmental sequence as already said,
demonstrate the importance of rhodoliths
for microalgal ecology and biodiversity
in those deepwater habitats.
And then, that the interiors of those rhodoliths
are marine biodiversity hotspots,
and also that, even though many of the macroalgae,
the large front of the macroalgae are still not present,
offshore Louisiana,
offshore the western-most banks, offshore Louisiana,
the cryptic microscopic stages
are present inside rhodoliths
and this has potentiality of regeneration in the field,
which we haven't seen much of it.
So happily, the oil spill did not reach the Flower Gardens,
so they stayed very healthy and full of diversity,
whereas offshore Louisiana, where we all,
where we went back in,
where close to where we are, close to Lafayette,
it's still very sad,
and when we go, we barely can see anything alive.
And it's the same with crustaceans,
where we, a person who does crustaceans,
and also one who studies molluscs.
And there too, those crustaceans,
and of molluscs have not increased either,
after 12 years now.
So this is kind of, scary a little bit.
So also what we have learned,
is that those life history stages,
that are, that go inside those rhodoliths,
those life history stages of macroalgae
may be much more common than is currently understood,
because a lot of those macroalgae form blooms,
and there's a lot of bloom-forming algae,
where do they they come from?
We don't know.
Well, I think some of them
may very well come from hiding to those rhodoliths.
So this is also very interesting for future research.
And we know those rhodoliths are very important
in understanding algal community cycling,
to just completion of life cycle
and then also for resilience
and so, very interesting.
And that the environmental sequencing
what it has done,
opened the door to assess the universality
of those endolithic stages
of bloom-forming macroalgae,
that span many different phyla
or divisions, as they're also called,
very high-level roles in marine ecosystems worldwide.
So we can ask, how do actually-
what is the dynamics of those stages,
those weird life history stages of this macroalgae,
inside a rhodolith?
This is for the surface of the rhodolith
and you peel, you cut it off,
and then you see all those cells,
that has a weird stage in it.
And those cells-
I don't see it again.
Just a minute.
Oh, where there was a little arrow that was on some stages
and look some of those weird stages,
like these three stages,
and you see there everyone has basically every hole,
every cell interior has one of those weird stages.
And surrounded the whole of the cell,
again, we see it's all calcium carbonates.
So we still don't know exactly what the point of entry is,
inside that interior of the rhodolith, and how they get out.
But, so we think, so that we still don't know.
So what I'm gonna to say is purely speculative
at this time.
So we speculate that biogenic rhodoliths species
because coralline algae,
a lot of them slough off off their surface layer.
So they have a surface layer
that it can be immediately, wipe it off,
it disappears and it could be that because of that,
with all that type of tissue,
that's now open to the elements,
maybe it can harbor those populations
of those macroalgae that are not there permanent
but perhaps are transient life history stages.
So that this, perhaps this is true.
And then once those stages can then make blooms,
once they are released in the water column
from the interior of the rhodolith,
because remember, they are rolling stones,
so they often they can, there's a lot of abrasion,
so they roll and some parts can also slough off like that.
And perhaps like that,
all those weird stages become part of the rhodolith,
and then the rhodolith, the coralline forms,
which goes on top of it.
So that's perhaps what happens.
And also, you see here, where there's the arrows,
we see those big holes.
Like those are actually pit connections, openings,
who basically connect the different cells.
And those openings are like the same size
of those microalgal stages.
So maybe they can go through,
they can travel through those pit connections.
We don't know.
And alternatively, also we see here,
what is this, oh, we see here there's rhodoliths
with a whole bunch of holes in it.
And those can be borers
it can be animals that bore into the calcium carbonate,
and those too, those borers,
could also be responsible
for releasing those microalgal stages by opening burrows,
and then releasing those microalgal stages
to the water column.
And that too is really fascinating,
because of the coupling
of bentho and planktonic type of life histories
and how this all is so important,
based on those rhodoliths.
So they are really-
we think completely fascinating organisms from that.
And so this we did on the rhodoliths,
more westward from Louisiana hard banks.
So we would like to conduct research too,
to see whether the same phenomenon occurs in the rhodoliths
on the Flower Garden Banks.
And so this is all on the agenda
but it takes much time to do all the research
and we couldn't do it, for the most part of 2020,
so hopefully later in the summer
and so we can continue doing all our research.
So if you do research,
we like to do the Flower Gardens,
it's to continue our biodiversity research,
but evolutionary relationship research
about geography of all those mesophotic algae
in the Flower Gardens,
and we will do that of course,
in collaboration with, Emma Hickerson and Marissa Nuttall.
So there's so much to do
and also future research what is needed,
what would be really interesting to do,
is study these historical samples,
to assess shifts in communities,
and then the effects of global warming,
and ocean acidification on these calcifying organisms
and those crustose corallines.
And also what would be interesting
is to study the contribution of the rhodoliths,
in understanding large-scale ecosystem processes
such as community structure, biogeochemical cycle,
and also to unravel the whole complexity
of that whole rhodolith ecosystem.
At individual level, one rhodolith at a time
or at the whole community level,
in those big rhodolith beds.
And also look at the interactions
between microbes and predator-prey interaction,
symbiotic associations,
characterizations of the transport
of nutrients and energy, etc.
So there's so much to do
when we just look at those rhodoliths
and they are very easy to keep
when we want to do DNA sequencing,
because we can just keep them in some silica gel,
or some cat litter, what we see in that blue,
and we keep it, it's okay for years we can have them.
So that's how we can always go back
what happened 10 years ago.
We can sequence it and we're gonna get nice DNA sequences,
to then compare with the sequences from other species
or from the same species from other areas and so.
And we keep them alive.
So basically, this is what I wanted to convey,
is that those algae in the Flower Garden Banks,
are so fascinating to study
and because also they are those,
especially those coralline algae,
are so important to the whole ecosystem
of the whole Flower Garden Banks.
So that's what I wanted to say.
Kelly: Thank you, Suzanne,
and we're right at 7:30, so folks,
I understand we haven't had time for questions yet,
but Suzanne has agreed to stay on with us
for another 10 to 15 minutes.
So, I'm gonna go ahead and do the normal wrap up,
for those of you that need to leave,
right now at 7:30,
and then if you'd like to stay on with us,
Suzanne will answer questions for another 10 to 15 minutes.
So Suzanne, I'm gonna to grab the control back from you
to show my slides again.
-: Do I need to do anything? No...
Kelly: No, just hang out there, one second,
and we'll be right back to you in a moment.
Depending on the number of questions we have left
at the end,
after we get Suzanne to answer a few of them,
we will attempt to get more answered
after the webinar ends
and if we do, we will email out those responses to everyone.
Please, also remember to check out
the links we've shared with you in the chat box
throughout the course of the webinar,
we've provided the link to Suzanne's seaweeds lab,
as well as to some photos of more rhodoliths
and things at some of the banks
in our expansion areas of the sanctuary.
And don't forget we have a PDF of that one paper out there,
about rhodoliths as a biodiverse ecosystems,
as biodiversity hotspots,
I think was the wording in the paper.
So that's also available in the handout pane of our webinar.
Thank you for attending
this Seaside Chats presentation on Remarkable Algae
of Flower Garden Banks National Marine Sanctuary.
The image on this slide shows the algal nodule habitat
full of colorful reef fish from Bouma Bank,
one of the new expansion areas
for Flower Garden Banks National Marine Sanctuary.
This is the last of our Seaside Chats presentations
this year, for 2021,
but we invite you to check back in with us next January
at the flowergarden.noaa.gov website
to see what we'll be offering
for our 2022 Seaside Chat season.
We also welcome any feedback or further questions
and you can submit input
by replying to the followup email you'll receive,
or by emailing us flowergarden@noaa.gov.
Today's presentation has also been
part of the National Marine Sanctuaries Webinars Series,
and while Seaside Chats lasts just one month each year,
our National Webinars series continue throughout the year
to provide educators with educational
and scientific expertise, resources and training,
to support ocean and climate literacy in the classroom.
Be sure to check the website
for recordings of past webinars,
and a schedule of what's to come.
As a reminder,
we will be sharing the recording of this webinar
via the National Marine Sanctuaries webinar archive,
and also on the Flower Garden Banks
National Marine Sanctuary website.
So, we will notify you when those links are available
for the recordings of this presentation.
Following this webinar,
all attendees will also receive
a PDF copy of a certificate of attendance,
that provides documentation for one hour
of professional development for today's presentation.
If you are an educator outside of Texas,
please use this certificate
to help you get your hours approved in your own district.
For those of you in Texas,
we have provided our Texas CPE provider number,
and you will need that to get your credits
at your school district.
If you require additional information,
please contact me, Kelly Drinnen, at flowergarden@noaa.gov
and I'll be happy to help you out.
There will also be a short evaluation
that has questions for you to answer
following today's presentation.
Please complete the survey
immediately after signing off the webinar,
and it should only take about three minutes of your time.
We greatly appreciate any feedback you are willing to share.
Thanks again, to Suzanne for a great presentation
and for the willingness
to hang out a little bit longer with us
and answer some questions,
and thanks to you all for taking the time
to join us this evening.
This concludes the main portion of the webinar.
We will now go into just a continuation
with our question and answer period.
We hope you'll stick with us.
So, Suzanne, you don't have to worry anymore
about screen anything.
I'm just gonna to share questions with you at this time,
and you can just stay on camera for everybody,
if you'd like to turn your audio back on.
-: Back on?
Kelly: Yes. There you are, I hear you now.
So the first question is,
Does this represent something like succession
in terrestrial systems,
where the rhodoliths are replaced
by the settlement on top of them,
or do they persist despite that settlement?
-: Well, I think it depends on the type of species.
Some of them
(keyboard clicking) were on top of one another,
so there is a succession,
because you mean like the algae,
are they successional? Yes.
In spring you're gonna see less algae, fleshy algae,
than in late summer,
like when we go September or something,
end of August, September.
That's the real peak for the fleshy algae
in the Flower Gardens.
But we never, from the pictures, I know that,
because we haven't really personally been going to those
in the winter or in the early spring.
So I've only been in the late summer.
But from the images that Emma showed,
there are less fleshy algae in the winter and early spring,
than in late summer.
So there is a clear succession, yes.
Kelly: Okay.
Next question-
-: Corallines, don't know how they work
because we don't have many specimens.
It's very difficult to recognize those corallines
just from an image.
As you can see, you have to either extract the DNA from it,
sequence it or look on the, looking at the anatomy, etc.
So we don't know whether some, the same rhodoliths
that we find in the Gulf, in the Flower Gardens,
in September, October,
or do we also find in very early on.
So that, what kind of shape they are in,
that we don't know.
Kelly: Thank you.
Next question,
for the rhodoliths, -: Yeah.
Kelly: For the rhodoliths that are collected
with the ROV,
do you keep them in aquaria on board,
or do you pack them in bags,
like we saw in your photos there?
Or how are they kept bring them back to you?
-: We bring them in big coolers,
with some oxygen,
like when you want to keep fish alive.
So we bring them in big coolers with oxygen bubbles.
Once they come on board,
we have a whole bunch of coolers
and then we take them to the lab,
and there we have already those microcosms,
those big aquarium ready.
We just need to add the water into and the material.
And then everything is ready to study.
Kelly: Okay.
-: We collect them on board, we bring them with us
back to Lafayette,
and there we transfer them into microcosms,
along with the water that each particular alga
and collection of algae was collected from.
So we know that we have no cross contamination,
that those rhodoliths come along with their own water.
Kelly: Have these endolithic life history stages
of macroalgae been noted in shallow reef rhodoliths?
-: That I don't know.
No, they have not,
but I haven't looked at shallow reefs
and we have wonderful reefs
like even in West Africa and so,
that are intertidal.
But nobody, I think has looked at the inside of it.
So I don't dare to say. We don't know.
Kelly: Okay.
Question about... -: Don't know (chuckling).
Kelly: That's okay.
The large-bladed fleshy red algae
that was in some of your photos,
what's the taxonomic identity of that red algae?
-: Halymenia. Some are, it's a Halymenia.
A new species (indistinct) (keyboard clicking)
with the big blades,
wonderful red blades.
It's a bit gelatinous, yeah.
Kelly: Wonderful.
All right, if autogenic rhodoliths are the calcium carbonate
left after biogenic rhodoliths die,
or is their origin completely different?
-: The origin is different.
The origin is from what's that stuff,
it's the rubble that is calcium carbonate.
And like you remember when I said about
that salt gets transformed into calcium carbonate
with the help of bacteria.
So you have a lot of rubble that already exists
at the bottom.
And then it's some of that rubble,
that gets covered, grown over, by certain corallines
or some brown algae or some animals.
Like some soft corals, they can attach to it.
So those are the autogenic one.
And so the biogenic one are the ones that are ...
the rhodoliths that are formed only
from the coralline algae themselves.
The other one is rubble that gets covered secondarily
by corallines or other brown algae crusts.
But the biogenic one, starts with a couple of cells
and continue to grow and grow,
into those biogenic ones.
And they're always much smaller than the big ball
the stuff can be.
Those nodules that are autogenic.
Kelly: Okay.
Do the macroalgal rhodoliths grow in annual layers?
Is there any way of telling annual growth patterns,
like in trees and corals?
-: I think some people are working on that,
with some labs, who are the geologists
and so who are working on that.
And I think there is, in University of Alabama,
they are looking at things like that, but I don't,
I haven't, that's not something that I have followed.
But they try to see if there is an analogy about that.
See how all this goes, how old are they?
Those rings basically, once you...
So I don't know much about that.
Kelly: Okay.
-: Sometimes I can see, I don't see.
Kelly: Do rhodoliths and crustose coralline algae
perform similar functions in shallow water environments?
Can they contribute to neutralizing ocean acidification?
-: Yeah, they do,
because you can have shallow,
the coralline algae its important everywhere.
And, but some corallines have more calcite
and others have more proportion of aragonite
and they have studies that have been done,
not from, like in Australia and so
that showed that those corallines
that have relatively more aragonite in their cells,
resist better ocean acidification.
Those that have more the calcite as part of the limestone,
they are more sensitive to it.
So it's difficult to generalize too much
because they are different types of calcium carbonate,
some are more sensitive to the acids than others, etc.
But yeah, I think it's the same
whether it's very shallow or very deep,
because those corallines you find at all level,
but I haven't looked at shallow water rhodoliths,
except some in the tropical part of Panama.
And that's so...
Kelly: I'm gonna take one more question,
and that is, is the average thickness of the algae
on the nodules consistent or does it continually grow?
-: It basically can continually grow,
but they are rolling.
When we talk about those nodules,
they roll and then pieces fall off
and then they continue to grow.
So that's why they may look all different
but they all the same thing, the same species
and then others who look all the same,
but they all different species.
So it's very weird and they should keep us busy.
(Kelly chuckling)
Such great diverse, I never been in a place like here,
like the Flower Gardens on those trips
we went with the ROV, and on those other hard banks,
closer to Louisiana.
I never seen anything so rich in diversity of corallines,
it's absolutely extraordinary.
Kelly: Well, Suzanne.
We're so excited to hear your excitement
for what you do. (Suzanne cackling)
And the expansion areas are this wonderful new horizon
ahead of us to continue working and studying.
And we're happy to have you along for the ride.
-: Well, we hope so because all of us here,
in Lafayette,
we are all so excited about all the algae.
(Suzanne chuckling)
Kelly: Well, hopefully it continues to be
even more remarkable.
We learned some amazing new things in the coming years.
-: So many new things we still have to describe
and everything is crazy.
It's absolutely crazy to have such a rich area.
And I never knew that before I came to Louisiana in '96.
I never was,
I never knew about that.
But then we had (indistinct) who was the chairman
in the department of biology, and he had gone,
he knew the Gulf, very well.
And so he brought me along on some of those expeditions.
And then I was, oh my goodness.
So he completely changed the way we see algae
based on what we find here in the northwestern Gulf
and in the Flower Gardens.
Because all those very interesting phenomenon
that we found in the rhodoliths,
after the oil spill,
we haven't really seen some of those
in the Flower Garden rhodoliths
but we had to look at many more things,
many more-
Kelly: Well, I'm sure we're gonna keep you busy
for a long time to come.
-: Yeah. (both chuckling)
Kelly: Thank you so much, Suzanne,
thank you everyone for joining us this evening
and staying on for the extra question and answer period.
We're so excited to have you with us
and we hope you'll join us for Seaside Chats
again next year in 2022.
If you wanna stay in touch with us
at the Flower Garden Banks,
we have an email list you can access
from our website to make sure you keep hearing from us.
-: I have. -: And Suzanne,
if you have something to add?
-: Yeah. Well, thank you very much
for listening and for inviting me again.
So it's been a pleasure.
Kelly: It's been a pleasure having you.
Folks, that concludes today's webinar.
Thank you very much.
Suzanne: Thank you.
(Suzanne chuckling)
Goodbye. (keyboard clicking)