
The Hidden Gulf
Special | 26m 46sVideo has Closed Captions
Deep beneath Gulf waters, entire ecosystems live in total darkness.
Deep beneath Gulf waters, entire ecosystems live in total darkness. When the Deepwater Horizon oil spill threatened their existence, scientists raced to learn more about the life that lives on the edge of our knowledge. Join the experts who endure life offshore as they use cutting edge mapping, coral propagation techniques, and more to restore these important communities.
Problems playing video? | Closed Captioning Feedback
Problems playing video? | Closed Captioning Feedback
The Hidden Gulf is a local public television program presented by mpb

The Hidden Gulf
Special | 26m 46sVideo has Closed Captions
Deep beneath Gulf waters, entire ecosystems live in total darkness. When the Deepwater Horizon oil spill threatened their existence, scientists raced to learn more about the life that lives on the edge of our knowledge. Join the experts who endure life offshore as they use cutting edge mapping, coral propagation techniques, and more to restore these important communities.
Problems playing video? | Closed Captioning Feedback
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- [Announcer] This program is made possible through a grant from the National Marine Sanctuary Foundation with funding from the Deepwater Horizon Open Ocean Trustees.
The National Oceanic and Atmospheric Administration and the United States Department of the Interior are leading efforts for the trustees to restore deep sea communities injured by the 2010 Deepwater Horizon oil spill.
(gentle music) (gentle music continues) (gentle music continues) - Corals are marine invertebrates.
They are cnidarians, so think of them as similar to similar families as jellyfish or other things with stinging tentacles.
A lot of people think about warm tropical and subtropical corals that are found in shallow areas, think the Florida Keys, the Great Barrier Reef in Australia, or maybe in Hawaii.
- They produce calcium carbonate structures, this hard coral structure which is almost like a rock.
And that's what produce the shallow coral reefs of the world.
And most of the ecosystems in which there are corals, the diversity, the number of species that are there is orders of magnitude higher than in any other ecosystem.
For instance, if you go to a shallow water coral reef, it's estimated that 1/4 to 1/3 of the diversity in the ocean is in those places.
- People may be really surprised by this, but we actually find corals that live in the deepest and darkest places on Earth in our deepest oceans.
And as we descend into the water column, the light becomes more limiting and the temperature becomes colder.
- Mesophotic literally translates to middle light.
So these are areas in the ocean that receive a little bit of light, but not very much.
Typically, it's gonna be somewhere between one and 10% of the light levels that you might see on the surface.
Now, deep benthic communities are the sea floor communities that are far enough down that they receive basically no light.
The light will attenuate or get less as things go down.
You lose various wavelengths.
You lose your reds first.
And so, going down, you get your indigo and violet wavelengths of lights that penetrate further down, and eventually go to nothing.
- Most of the deep water corals, they are more flexible.
They don't have this rigid, rocky structure.
They are more like a branch, like a bush, and they are kind of erect in the water column.
And they are mostly eating by filtering, collecting particles from the water.
- As we descend into the water column, temperatures become lower and lower.
It becomes colder and colder, and the animals slow down.
Their metabolic rates become slower and they grow more slowly.
I am struck by the ages of corals that we've been able to age in the deep sea, in the mesophotic environments.
Many of them can be tens to hundreds to thousands of years old.
So a colony that may be a foot or two feet high may have been around for hundreds of years.
- Lots of corals are relatively slow-growing, so they're really susceptible to a whole multitude of dangers.
- There has been a lot of human activities, and those human activities have produce detrimental issues to those ecosystems.
- Fishing activities, fishing line, that could potentially get entangled in corals.
These are really fragile organisms that are attached to the sea floor and don't take a lot to knock 'em over.
There are animal threats such as invasive species like lionfish.
We also have other human types of impacts, including oil.
(gentle music) (helicopter rotors thrumming) - On April 20th, 2010, I remember it clearly 'cause I was actually at work that day and was down helping some divers at our facility, build some underwater pens for sea turtles.
It was kind of a very surreal moment when they say, "Oh, wow, there's a big explosion, lots of oil.
Looks like they could have a lot of trouble capping it."
As the days and weeks went on, realized this was not just a normal incident.
It was really unprecedented in the scope and scale.
- People don't realize how long that oil was not capped for.
The oil spill and the explosion happened in April, and that didn't get capped until July.
So it's just so much oil that's just pouring out into these deep water communities.
- When we saw the initial images of the oil spill in 2010, what we initially saw was the slick at the surface of the water.
But what wasn't obvious, what wasn't visible was that the oil also was being injected at the bottom.
Because it was exposing environments throughout the water column from the top to the bottom, there were organisms from really tiny bacteria all the way to big animals that were impacted.
- In the days and weeks around the incident, there's a lot of scrambling.
- [Amanda] We had to essentially assess the impacts to these different environments in a really scientifically robust way.
- People start quantifying the amount of the damage.
And in the coral world, that was going out to the sea with mostly ROVs and trying to go colony by colony, trying to say, "This is in good shape, this is in bad shape, this is somewhat affected," and quantifying the amount of that damage.
So we start seeing all these pictures of corals in the deep ocean full of oil.
(camera clicks) (somber music) - [Amanda] They're basically stuck in the mud or on the sea floor.
They can't run from this catastrophe.
(camera clicks) (somber music) (somber music continues) (no audio) (gentle music) (gentle music) The goals of the The goals of the mesophotic and deep benthic communities' portfolio is to gather information to better understand mesophotic and deep benthic communities.
Those data can be used to inform management decisions Those data can be used to inform management decisions like where to protect these organisms.
- The overarching mission of this project - The overarching mission of this project is restoration for mesophotic and deep benthic communities impacted by the 2010 Deepwater Horizon oil spill.
One of the most direct ways we can do that is to propagate corals.
We can cut off portions of the organism, We can cut off portions of the organism, and then glue them to a substrate, and then put them back, and these will grow into new organisms.
and these will grow into new organisms.
Think of it like coral gardening.
- To help improve the health of these communities that were damaged by the oil spill and to improve the full community ecology.
- We could do that because corals are colonial organisms.
So if you look at a coral very close, you're gonna see that there are things that look like my hand.
And you have the replication of that And you have the replication of that across the colony, right?
And then the colony look like a bush, but that bush is composed of thousands of these replicates.
but that bush is composed of thousands of these replicates.
They are identical replicates, genetically identical.
So if you cut one of those little things and put it into another structure, you remove it from the colony very carefully and put it in another place, then you will have ano a new colony, identical to the one that you have before.
- This can happen either in a nursery area where we put it back where it was from, or sometimes in the lab where we'll take them back and try to grow them and then use them for spawning stock.
- Collecting samples of corals takes multiple steps and a lot of preparation.
Those collections occur at depth.
Those collections occur at depth.
A small snip of sample of those coral branches are clipped off, placed into some sort of container.
It's sealed at depth so that the temperature remains constant.
When we're bringing up corals, When we're bringing up corals, there are specific people who have specific tasks, and that included us taking the coral snips or coral fragments, attaching them to a substrate, a rock, a rack, and then redeploying that rack out into the ocean onto the sea floor.
- And once it's done on deck, we have the whole process of getting it back down.
You don't really wanna just toss these things over the side.
So we fabricated, we're calling it a coral elevator.
Basically, it's some big tubs that we can put water into, and then crane over the side with live corals lower to the sea floor.
So either an ROV or divers can take them and put them in the appropriate places.
- And that's just the start.
- And that's just the start.
So once we then come back to the dock, we have aquarists at the federal labs and in our partner labs who are working really hard to make sure we get those corals back into the lab facilities into the laboratory aquarium.
A fundamental aspect of us being able to do the work at sea A fundamental aspect of us being able to do the work at sea is to have good maps.
The existing maps that we have for areas The existing maps that we have for areas in the Gulf that we're targeting are not at high enough resolution for us to determine where we might find corals, where we might find habitats of interest.
like mesophotic and deep benthic communities.
They're fuzzy.
They're fuzzy.
It's like taking a map on your phone app and seeing essentially a lot of streets, but you can't see the street names.
By going offshore and collecting more mapping data at higher resolution, we start to see more, and it gets into more detail.
- We'll use sonars.
- We'll use sonars.
Sound is emitted through a transducer, goes down, bounces off the sea floor, and comes back.
By listening for that sound, we can tell really accurately how deep it is, but from kind of the tone of the sound that comes back, we can get some idea of the sea floor also.
Despite all the efforts we're putting into it, Despite all the efforts we're putting into it, we still need to go take images at the bottom and match that up with sonar so our modelers can go in and make predictive maps of where they think these habitats will be.
- We're taking remotely operated vehicles to take a look.
The ROV, remotely operated vehicle, can help give us images of the sea floor to help confirm where we might find corals.
It takes a lot of different innovations and technologies It takes a lot of different innovations and technologies to collect sea floor maps.
to collect sea floor maps.
It takes a lot of people and expertise to collect the samples from the sea floor and then make information or understand those environments.
(no audio) (no audio) (no audio) (machine whirring) (machine whirring) (machine whirring) (machine whirring) (waves crashing) (waves crashing) The SATFADS mission took place The SATFADS mission took place in the Flower Garden Banks National Marine Sanctuary, which is located in the western Gulf.
It is an area that serves as a really great reference It is an area that serves as a really great reference of healthy coral environments, which are helping us understand the coral habitat, the communities of organisms that are supported and serve as a reference for areas that may have been impacted by the spill.
The SATFADS expedition I would say is The SATFADS expedition I would say is one of the most complicated expeditions in my career.
We're working with saturation divers, We're working with saturation divers, humans that are going underwater to do this really intense work.
We also had a remotely-operated vehicle on this expedition.
We also had a remotely-operated vehicle on this expedition.
So we're putting a vehicle in the water to go deeper and collect samples.
A lot of moving parts, A lot of moving parts, a lot of potential areas for things to go wrong.
It can be incredibly nerve-racking.
It can be incredibly nerve-racking.
Every minute is accounted for.
Every minute is accounted for.
Those minutes represent the science objectives Those minutes represent the science objectives of multiple people.
We can't explore every aspect of the sea floor with an ROV.
We can't explore every aspect of the sea floor with an ROV.
We can only cover a little ground each time.
We can only cover a little ground each time.
And when we're looking for corals, trying to figure out where to find them, it is like looking for a needle in the haystack.
And so when we're doing these transits between locations, And so when we're doing these transits between locations, there is a sense of urgency and a sense of, there is a sense of urgency and a sense of, I guess, nervousness.
I guess, nervousness.
We wanna make sure that we're not missing anything.
(gentle music) (gentle music) (gentle music continues) (gentle music continues) - I picked out a transect - I picked out a transect based on the bathymetry on the map, kind of going up slope from a deeper area, kind of going up slope from a deeper area, and then going into a ridge line with some rocky outcroppings.
At first, some of the areas that upslope, At first, some of the areas that upslope, it was not as rocky as I expected.
The terrain was right, but just it was a finer sediment than I expected.
- [Carlos] We thought that we were going to find - [Carlos] We thought that we were going to find this coral from about 75, 70 meters to about 95, 100 meters.
And so we went all the way to 110 meters, and then we started to not see anything.
and then we started to not see anything.
- We haven't found the habitat that we were looking for.
- We haven't found the habitat that we were looking for.
We haven't found the marker on the sea floor that has all of these corals that we're looking for.
We may have to make decisions, really difficult decisions to move on to the next task so we can ensure we get the rest of the work done.
We're dealing with a real time sensitive issue.
We're dealing with a real time sensitive issue.
- Corals need many aspects, but one of the major ones is to have a hard bottom because the larvae is gonna be in the water column, and then eventually once the larvae is ready for settlement, it's gonna look for a hard spot.
And that hard spot needs to be devoid of sediment, otherwise the sediment will smother the coral and then it will die.
So in some of the time that we were in the ROV, So in some of the time that we were in the ROV, we saw some rocks which are hard sediments, good places for larvae to settle.
Yet we didn't see corals there.
Yet we didn't see corals there.
- All the clues pointed to that this direction was right, - All the clues pointed to that this direction was right, and you're not finding that, and it's very nerve-racking and... You wanna try to make sure you're being efficient with your time on the sea floor, but we need to find the corals in order to do our work, to do the science that we planned.
And so that stress is palpable.
It's not just me.
Everyone in the room is just keeping their eyes peeled, on the monitors, making sure we're not missing something obvious.
- And so it was kind of unsatisfying, what's happening, why the corals are not here.
Let's go back.
Let's go back where we started, and let's move a little bit higher in the water column.
And so that was almost at the edge And so that was almost at the edge in which we were calling off the operation of the ROVs.
(gentle music) (gentle music) And so it was kind of like this last 30 minutes, an hour And so it was kind of like this last 30 minutes, an hour that we found the corals.
that we found the corals.
(bright music) - All of a sudden, we see this gorgeous piece of coral, - All of a sudden, we see this gorgeous piece of coral, and it's just like the light was on it.
and it's just like the light was on it.
It was that ah moment where you just see the coral, it's there, and it's the first time we've seen it in this whole trip.
- We start seeing a small coral and then another coral, - We start seeing a small coral and then another coral, and then, oh, let's move a little forward.
Let's move more into the rock, and then we've seen more corals.
And then you start seeing the big coral, the big, big colonies.
When you find them, you generally really find 'em.
When you find them, you generally really find 'em.
They'll be very sparse and then all of a sudden you'll have a really high density area.
And so from there, we just went into kind of a collection mode, trying to find specimens that we could take a snip off.
- Once the ROV comes back to the deck, - Once the ROV comes back to the deck, then we take those corals out of the bio boxes or their containers, put them into other containers in the aquaria.
Everything is done under controlled conditions.
Everything is done under controlled conditions.
So we can keep those corals as stress-free as possible.
And then we get to do the science.
And then we get to do the science.
We could learn more about what those corals are doing, how to keep them healthy.
We are learning those fundamental aspects of the corals, We are learning those fundamental aspects of the corals, their biology, their physiology, and that information helps us better understand areas that we may wanna protect in the future.
(water gurgling) (gentle music) (gentle music) - [Chris] One big thing with this project is - [Chris] One big thing with this project is we are responsible for putting out more corals than we take.
So everything that we do and take from the sea floor is very intentional.
- I value making sure - I value making sure that we share this information with the public.
And the public aquariums, including Audubon, have established these exhibits.
Through the hard work of our team and the hard work of the aquariums, we've been able to share our science, share the beauty and vibrancy of these mesophotic and deep benthic communities with the public, and maybe that will inspire them to become ocean scientists or ocean engineers, or at least have value in our ocean environment.
- For me, it's really - For me, it's really this whole thing is about looking towards the future.
this whole thing is about looking towards the future.
This has a chance to really work and to go back, This has a chance to really work and to go back, give nature a good headstart from some things that we've caused.
from some things that we've caused.
- The ecosystems are slowly kind of healing.
- The ecosystems are slowly kind of healing.
If we provide some tools for them to accelerate that healing, I feel that that remediation process is gonna be a lot better, and more sustain, and probably sustaining the future than what is happening in some other shallow water ecosystems.
(gentle music) The most common estimation of the growth of these corals The most common estimation of the growth of these corals is about two centimeters a year.
And so it will take probably decades And so it will take probably decades to really see the fruits of this work.
But so far what we've seen in But so far what we've seen in the experiments that we've done and the things that we have done in the ocean, everything has been looking in the right direction.
Every year, we are more convinced that Every year, we are more convinced that they are going to survive and they are going to do better in the future, and that's a good thing.
(gentle music) (gentle music) (gentle music continues) (gentle music continues) - The National Marine Sanctuary Foundation - The National Marine Sanctuary Foundation is honored to be a key partner in restoring mesophotic and deep benthic communities in the Gulf.
The foundation is a leading voice for US National Marine sanctuaries, including the Gulf's Flower Garden Banks National Marine Sanctuary.
We are proud to aid this work through developing aquarium partnerships, supporting ROV operations, and bringing the public face-to-face with restoration through education and outreach and more.
This restoration work isn't easy, but it's crucial to ensuring these ecosystems thrive for generations to come.
- The Department of the Interior and NOAA are leading projects for the Deepwater Horizon Trustees to restore the deep sea communities in the Gulf that were injured by the 2010 Deepwater Horizon oil spill.
Scientists and resource managers from the US Geological Survey and Bureau of Ocean Energy Management were some of the first members of this team implementing these restoration projects in the Gulf.
It's remarkable how much we have been able to understand about these understudied habitats in such a short amount of time.
- NOAA is involved in every aspect of the mesophotic and deep benthic restoration projects.
From coordinating at-sea missions to growing and caring for corals in our labs, we're honored to be part of this dedicated team.
Together, we've made great strides to advance and share the science needed to better understand these habitats and how to restore them.
The partnerships we've formed through these projects will allow us to continue this work to ensure resilient and thriving marine communities in the Gulf.
(gentle music) (gentle music) (gentle music continues) (gentle music continues) (gentle music continues) (gentle music continues) - [Announcer] This program is made possible through a grant - [Announcer] This program is made possible through a grant from the National Marine Sanctuary Foundation with funding from the Deepwater Horizon Open Ocean Trustees.
The National Oceanic and Atmospheric Administration and the United States Department of the Interior are leading efforts for the trustees to restore deep sea communities injured by the 2010 Deepwater Horizon oil spill.
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The Hidden Gulf is a local public television program presented by mpb