They are always out there.

At any one time, if you
take a drop of water

from anywhere in the oceans,

you'll literally see hundreds
of different species.

But sometimes,
algae grow out of control.

What we're
really concerned about

is the frequency and the
duration and the intensity

of these blooms.

Harmful algal blooms

have dominated the headlines.

What used to
be isolated blooms

are now becoming very,
very common and widespread.

And they are
affecting the ecosystem.

I think even just
looking at our historic numbers

we saw higher numbers in
our area of strandings

this past year with both sea
turtles and marine mammals.

But how are
they impacting human health?

You can end up in
the hospital for weeks.

And will
they ever go away?

One thing we do know

is we seem to be seeing bigger
and longer-lasting blooms.

23 00:01:26,400 --> 00:01:26,900
Major funding for this program

was provided by the
Bachelor Foundation,

encouraging people to
preserve and protect

America's underwater resources,

and by the William J. &
Tina Rosenberg Foundation,

the Do Unto Others Trust,

and by the following.

(tense music)

Algae are
aquatic plant-like organisms

that include a broad
range of species

from microscopic phytoplankton
to large seaweeds.

They are the energy
producers of the sea.

At these low levels,

they're a food source
for other organisms.

It's just at the high
levels, where we get blooms,

where they become,
if you will, killers.

When algae
grow out of control,

they can cause
harmful algal blooms.

So, harmful algal blooms
are just occurrences of algae

that have some kind of
negative repercussion

either to the
environment or to humans,

either human health, economy,
tourism, things like that.

Harmful algal
blooms have been reported

in Florida since the time of
the Spanish Conquistadors.

What is changing now,
these things occur naturally,

these are algae that have
existed in the oceans

long before we even had
societies as humans.

They're starting to
grow more frequently

into these harmful algal blooms

and spreading out where
we see them in our waters.

So, what used to
be isolated blooms

are now becoming very,
very common and widespread.

So, this is a problem.

57 00:03:19,400 --> 00:03:21,380
Florida Atlantic University's

Dr. Brian Lapointe is
an algae specialist

interested in how
nutrient pollution

affects algal blooms.

To figure it out, he samples
the macroalgae sargassum

from his lab in
the Florida Keys.

We have many, many species,

but Sargassum natans
and Sargassum fluitans

are the only species
that have adapted

to this floating life
on the ocean surface.

A common
sight in the tropical

and subtropical ocean,

sargassum mats are
important for the ecosystem.

Sargassum in its natural
state is a very positive thing.

Sargassum that is floating
on the ocean surface

supports a diverse array
of invertebrates and fishes

that are associated with it.

Some of these are
endemic, in fact,

they don't grow anywhere else.

But like any algae,

sargassum can grow
out of control,

causing a harmful algal bloom.

What we've seen
happen, just since 2011,

is what I call too
much of a good thing.

These dramatic
increases in sargassum growth

are thought to be
caused by increases

in nutrients in the water.

We have some major
river discharges,

all carrying increasing
nutrients to the coastal ocean,

where they become
available to sargassum.

But other factors as well,

such as atmospheric deposition,

rainfall carrying increasing
amounts of nitrate,

for example, can be
playing another major role

in delivering more
nitrogen to sargassum.

And while sargassum

is not a toxic marine algae,

coastal communities feel
the negative impacts.

The
infrastructure to deal

with these excessive amounts
of sargassum is just not there.

We've never had to
deal with this before.

I hear from resorts
around the Caribbean

that are literally
ready to shut down.

They are powerless
to do anything

to deal with this problem.

They've tried a
variety of things,

they tried to haul
it off the beach,

and that might work on certain
days when the wind is low,

and the currents aren't strong.

But ultimately, forces
of nature overcome.

One theory
is that a sargassum bloom

might trigger other
kinds of algal blooms.

As the sargassum decomposes,

it releases chemical compounds,

including nutrients that
can become problematic.

Logically, anything that's
gonna fertilize the oceans

and give a release of
nutrients is a problem.

(dramatic music)

As part
of his research,

Dr. Malcolm McFarland
regularly takes water samples

from Florida's
Indian River Lagoon.

So, this is a device
that takes a measurement

that is very similar to
what a satellite might see

orbiting the Earth.

It basically measures
the color of the light

that is reflected

from the surface of
the water back upwards.

We generally sample once a
week or every other week,

it depends on what
time of year it is.

We like to keep tabs on
what's going on out there.

These are basically plants,

so they require fertilizer,
just like land plants do.

A lot of those nutrients
come from agricultural runoff

or sewage treatment plants,
people's septic systems.

All these sources are
increasing the amount

of nutrient pollution that
is entering the lagoon

and other coastal waters.

One species
Dr. McFarland monitors for

creates what is
known as brown tide.

The brown tide
refers to a species

called Aureoumbra lagunensis,

and this is especially abundant

in the very northern parts
of the Indian River Lagoon,

near Cape Canaveral.

Brown
tide makes the water

look like chocolate milk.

The water turns
brown, dark, dark brown.

So, at nighttime, they're
actually using oxygen

just like we do,
for respiration.

They can draw down the
oxygen in the water,

and they can cause a fish kill.

So, all the other organisms
that are in the water

that need oxygen suddenly
can't breathe, essentially.

It's an unusual species
that a number of years ago

was associated with deep,
open ocean environments,

but it has found a
niche within these

coastal lagoons here in Florida,

and also over in Texas.

It is a very small cell.

So, it's only a little bit
bigger than most bacteria,

but it gets incredibly abundant.

As far as we know,
it is not toxic.

It has not been
terribly well-studied

as some of the other
organisms, like the red tide.

Red tide is
another harmful algal bloom,

one that does produce toxins.

Severe red tide outbreaks
have made headlines as fish,

some as large as whale sharks,

as well as sick or dead sea
turtles and marine mammals,

have washed up onshore.

Red tide generally refers to

a bloom of a species
called Karenia brevis.

It's a type of dinoflagellate,

which is a type of
phytoplankton that is common

throughout the world's oceans.

And generally, when it
gets very abundant,

it can discolor the water
red, hence the name red tide.

It's a really
interesting creature.

It has animal-like
characteristics

and it has plant-like
characteristics.

The animal-like characteristics

is that it has a
couple flagella,

and it can actually
swim up to the surface.

The plant-like characteristics
are that it photosynthesizes.

So, it's in one of
these unique categories

that have a little mix of both.

Karenia brevis is
particularly bad, um

it produces a toxin
called brevetoxin.

That's where the
Brevis name comes from.

It is a neurotoxin.

Red tides
are a regular occurrence

off the Florida coast.

Florida gets them
pretty close to annually.

Now people will kinda
scratch their heads at that

and say, oh, I remember
such and such a year there,

we didn't have any
dead fish on the beach.

Sometimes the way the
physical oceanography works,

there's a red tide perhaps
sitting 10 miles offshore,

but the currents are such

that they don't
get pushed onshore.

In 2017, there
was a severe red tide outbreak

off the west coast of Florida.

The extensive bloom lasted
nearly a year and a half,

even making its way to
the east coast of Florida

for a few months, which
is a rare occurrence.

It got advected over,

most likely through
the Florida Current

and up through the Gulf Stream,

up into the east
coast area of Florida.

We hope that is not a harbinger

of what may happen
in the future,

that the blooms
on the west coast

are getting bigger
and more persistent,

and because of that,
their chances of getting

moved over to the east
coast are now gonna go up.

And if the east
coast may start seeing

these same kind of
effects year after year.

During
that same outbreak,

Dr. Monica Lara conducted
regular reef monitoring

with her students
on the rocky reefs

off the west coast of Florida.

About a couple of weeks
after we believe the red tide

came through on
some of those reefs,

we did go out and dive,

and it was a
dramatic difference.

There were very few fish,

the invertebrates
were still there,

but there were some
bivalves that were dead

all over the place.

One of the theories, and
that's all it is, is a theory,

is that red tide
released the toxin,

the toxin gets in the water,

goes across the
gill slits of fish.

Again, it's a neurotoxin,

so it affects the
central nervous system,

and the fish quit breathing.

Kills the fish.

The reef was silent.

It's like the sounds from the
animals were completely gone.

So, it was like desert,
a silent desert.

It was really, really dramatic.

Once the dead
fish begin to wash up on shore

during a red tide event,

many birds start
to feed on them.

Early signs of a red
tide in and the seabirds

is kind of staggering,
drunk behavior,

or they won't be able
to stand or walk.

Kind of be placed on the
ground, just sitting there.

It really affects their
neurological system,

so they just are
kind of hopeless

until somebody picks
them up or they die.

Rescue groups
say seabirds of all sizes

were affected by the
red tide outbreak.

We actually see
the smaller birds,

like the ruddy turnstones
and the sanderlings, first.

They are kind of our
canary in the coalmine.

We'll see them immediately,

and then we start
getting the bigger species,

like the laughing gulls and
the double-crested cormorants.

Seabirds
are impacted not only

from eating poisoned fish,

but also from swimming
through bloom-filled waters

and inhaling the brevetoxin.

With fluid therapy,

the stronger birds are able to
expel the toxins and recover.

We release about
3/4 of the sick birds,

which for being such a bad
red tide was really good.

During
this severe bloom,

rescue missions
were also underway

at neighboring Mote
Marine Laboratory.

We had extremely elevated
numbers of strandings.

We've recovered over 300
sea turtles this year,

over 30 dolphins,

assisted with countless
manatee recoveries and rescues.

Marine animals
are affected by the brevetoxin

in different ways.

So, for our sea turtles,

they generally get it
through their food,

and it's a neurotoxin. They
get really disoriented,

they have a hard time surfacing
and clearing to get air.

So, a lot of the carcasses
we were recovering

had you know indications
of drowning.

If we can get to the animals
in time, we can get them help,

But, unfortunately, you
know, there aren't people
out there to see them.

Similarly, for the manatees,
it's also a neurotoxin.

They get that through their
airways when they're breathing.

And much like the turtles,

if we can get to them in time,
they can come out of it.

We've had animals that
we're holding their head

because they won't even
surface to breathe.

As we hold their head
and they're breathing

a little bit fresher
air that's not right at

the air-water interface,
they can come out of it.

And they can metabolize that
toxin and actually like leave

while we're waiting for the
rescue trucks to get there.

So, it's, um, that's,
those are always sort
of interesting cases.

And for the dolphins, we
don't have a great handle.

We know they get it
through their food,

but we haven't had any live
dolphins to respond to.

We know it kills them,

because we've recovered
many carcasses,

and most of the animals that
we've tested from the summer

had been positive for
brevetoxin at high levels.

So, we know that's acute
cause of stranding.

But I don't know how it affects
them when they're alive.

Humans are
also vulnerable to red tide,

since it can aerosolize,

and its toxic particles
can be breathed in.

A certain subgroup of
humans are very susceptible

to breathing the
airborne toxins,

and in particular, asthmatics
need to be very careful

when there's a red tide in town

to not be exposed to the toxins.

The good news is, everybody
reacts to the toxin,

and when you inhale it,
you get a dry cough,

you get nasal congestion,
you get eye tearing.

And why I say that's good

is that you know
you're getting exposed.

It's not like
something like radon,

that you have no knowledge of.

So, the important message
is, don't avoid the beach,

but know what
beaches are impacted

and what beaches are okay.

Brevetoxin
likely becomes airborne

through wave action.

Humans can also get
sick from consuming fish

or other seafood that have
been exposed to red tide.

Fish consume the toxin,

and the toxin accumulates
in the guts of the fish.

So, if we fish during a
red tide, and you filet it,

you won't get sick from
any potential toxin,

because the toxin's in
the guts of the fish.

We do need to educate people,

there are some cultures who
consume whole fish soup.

And so, they need to know
that during red tides,

you can't throw the
whole fish in there.

Your family potentially
can get sick.

The causes
of red tide blooms

still aren't clear,
although it is thought

that there has to be a
perfect mix of temperature,

oceanic conditions,
and nutrients.

During certain years,
the conditions seemed right,

that there's some
kind of a nutrient

that is added to the system.

And so, then they're able
to increase in numbers.

What that nutrient
is, we're not sure.

Whatever that nutrient is,

some experts say humans
likely introduced it

into the oceans.

Average abundance of red
tide on the west coast now

is about 15 times more
than it was 50 years ago.

To generate 15
times more red tide,

you need 15 times
more nutrients,

and I can't think of any
natural sources of nutrients

that have increased 15-fold.

But of course what has
increased dramatically

here in South Florida
over the last 50 years

is number of
people, agricultural
interests, and so on.

We're just driving
along the northern side

of the Caloosahatchee River

sampling in various
locations along there, right,

we just finished
sampling the Ortona Lock.

It's one of three
damns and locks

on the Caloosahatchee River.

And now we're heading
over to the west coast.

Red tide isn't the
only algal bloom

that's been wreaking serious
havoc in Florida waterways

in recent years.

Dr. Larry Brand has been
sampling for cyanobacteria

in the waters around
Lake Okeechobee

and in the Caloosahatchee
River for almost 20 years.

Well there's a lot of changes.

I can't really say for sure
there's been a longterm change

over the past 20
years, but certainly,

some years you have really
bad blooms of cyanobacteria,

and some years you have less so.

But it's very clear that

these are very
nutrient-rich waters,

and you often do get these
large blooms of cyanobacteria.

When water levels in Florida's

Lake Okeechobee get too
high, flood managers,

fearing a breach in the
dike surrounding the lake,

discharge billions
of gallons of water

through canals,
rivers, and streams

into the Gulf of Mexico
and the Atlantic Ocean.

This can bring nutrients
which have built up

in Lake Okeechobee
to the estuaries,

causing these algal blooms.

The cyanobacteria tend to
do better in warmer weather,

so we tend to get these blooms
primarily in the summertime.

'Course it's also
in the summertime

because that's when
you have more rainfall

here in South Florida,
that's the wet season,

so you get a lot
more land runoff,

and of course that's the
source of most of the nutrients

in Lake Okeechobee and
the Caloosahatchee River.

Various nutrient
sources on land,

and then during the wet season,

all that rain water flushing
those nutrients

into the water bodies.

Cyanobacteria are also known

as blue-green algae.

They were some of the
first organisms on Earth.

They're really tough, it's
really hard to kill 'em.

And we now know they produce
a lot of pretty nasty toxins.

They also produce over
1,000 other compounds

which simply have not
been characterized yet,

we have no idea what the
health hazards may be

when you're exposed
to these blooms.

But some of the best known
ones are for microcystin.

That can lead to
longterm liver damage

and even liver cancer,

and more recently
we've discovered a
compound called BMAA,

and there's increasing evidence,
pretty good evidence now,

that it can lead to
neurodegenerative diseases

like Alzheimer's,
Parkinson's, and ALS.

Blooms of cyanobacteria

are characteristically
bright green,

and can be as
thick as guacamole.

Every time I travel along
the Caloosahatchee River here

or along the shores
of Lake Okeechobee,

I see people fishing.

I know there's high
concentrations of
BMAA in these fish

and probably also microcystin.

I certainly would not eat
the fish in this river.

But I do see people doing so.

And there's no signs along
any of these water bodies

warning people about the
presence of these toxins.

Experts say the
biggest question now

is whether cyanobacteria
pose an even bigger,

more silent threat than we know.

Well right now what
we're focusing on is the

possibility of the toxins in
these blooms of cyanobacteria

getting into the air.

Now for the red tide offshore,

it's been known for
a long time that

that toxin gets into the air,

'cause it has immediate
effects on people's

eyes, nose, throat.

I call that a good toxin
in that you know right away

you're being exposed to it,

so you can do
something about it.

But these toxins here in
these blooms of cyanobacteria,

like microcystin and BMAA,

microcystin can have
short-term effects,

but the BMAA has no
short-term effects,

it only has longterm effects.

If that toxin is
getting into the air,

if you live near this river

or some of these
other water bodies

that get frequent
blooms of cyanobacteria,

you could be breathing in
this BMAA, not know it,

and then 10 or 20 years from now

you could come down
with Alzheimer's.

So it's a much more
insidious toxin.

To determine if cyanobacteria

can become airborne,

a multidisciplinary team
at the University of Miami

is working with Dr.
Brand's water samples.

The team designed a wave tank

to create conditions like
those at Lake Okeechobee.

We have a wind
wave tank set up

in order to blow air and create
more realistic conditions

for the transfer of the aerosols

across the air-sea interface.

So we're gonna
create this condition

where the wind's blowing
over the water surface

and see what's produced.

My lab does realtime
techniques to measure the size

as well as the composition
of these particles,

but if we wanna
quantify their toxins,

what we do is we collect
the particles on a filter,

and then Dr. Popendorf's
lab extracts the material

off of the filter and
uses her mass spectrometer

to quantify the toxins and
also figure out which toxins

are present in the samples.

So the two techniques
are really complementary

for understanding the
impacts of these particles

on human health.

This project
is in its early stages,

so the results
are still unknown.

But one researcher
from the medical school

is already anticipating
some interesting results.

My lab studies
neurological diseases,

including
neurodegenerative diseases,

and we use fruit fly as a model.

After exposing
some flies to cyanobacteria

from Lake Okeechobee blown
through a bubbler for an hour,

Dr. Grace Zhai noticed
some differences

in the flies' behavior.

So, there're
several behavior tests

to look at their
nervous system function,

and so, first one and
most commonly used one

is called a climbing behavior.

So what you can see actually

is normally flies would
climb up if I flip this,

all the flies started
to climb upwards.

This is the first time we're
running this experiment.

So, we can already see
an immediate difference

between these two groups.

So this one hasn't been exposed.

This one has been exposed
to the aerosolized particle

for one hour.

So can you tell
which one is faster?

Not all
toxins found in nature

are necessarily bad.

One of Dr. John Berry's missions

is to identify new compounds
in harmful algal blooms

that may actually be
beneficial to humans.

In one experiment, he
tests toxins he extracted

from cyanobacteria
on cancer cells.

We pulled out compounds
that people just,

they're not on the radar
yet, and that's the idea,

is to get some of these new
potential toxins on the radar

so that we can
start to understand

if they're having an effect.

They've been a real goldmine
for people looking for

biologically active natural
products for drug leads,

so, they're sort of these
toxin slash drug producing

little factories
out there in nature.

Florida has been hit hard

with multiple algal blooms
negatively impacting

the environment, human
health, and the economy.

The length and severity of
these blooms is getting worse.

People living along
Florida's biggest waterways

are clamoring for help in
putting an end to the blooms.

There are a number of people

who are starting to hypothesize

that we've hit a tipping point,

that the combination
of climate change

and the patterns of
rainfall and warmer waters

that we've gone through,

combined with all
the development

and land use practices
that we're doing

around our coastlines and
the nutrient pollution

that we're putting
into our waterways

has put the systems into
a very bad position,

that they're irrevocably harmed,

that we're not
gonna get them back.

I don't fundamentally
believe that,

I do believe if we can get a
control on nutrient pollution

nature will fix itself.

Nature is very resilient, it
just needs time to recover.

If we keep on beating
it and polluting it,

it's never going to
recover, and yes,

we'll be living
with this forever.

Major funding for this program

was provided by the
Batchelor Foundation,

encouraging people to
preserve and protect

America's underwater resources,

and by the William J. &
Tina Rosenberg Foundation,

the Do Unto Others Trust,

and by the following.