Changing Seas

(soft music) - [Narrator] Far out in the eastern Atlantic, a lush subtropical oasis rises from the depths of the open ocean.

This is Madeira, a volcanic island formed some 20 million years ago.

- [Filipe] Madeira comes straight from 4,000 meters depth.

- [Marc] We are an island in the middle of the Atlantic.

It's like a rock.

- [Laura] So in a few miles from the coast, we already go to 1,000 to a few thousand meters depths.

- [Filipe] It's super easy to study these offshore environments.

- [Narrator] This makes Madeira a hotspot to observe whales and dolphins.

- [Rita] Madeira has 30 species that have been identified here.

It's one third of the number of whales and dolphin species across the world.

- [Filipe] And of those, say 11 are known to use these waters on a regular basis for their vital activities.

(water splashes) These animals can swim a lot.

There are no physical barriers between countries or islands.

- [Narrator] The marine mammals are known to spend a lot of their time in a vast region known as Macaronesia.

- [Laura] Which is different archipelagos in the northeast Atlantic.

So Azores, Madeira, Canary Islands and Cape Verde.

- [Filipe] We know these oceanic island seamounts work as oasis in terms of productivity.

- [Narrator] But even remote archipelagos like Madeira aren't immune from plastic trash that's floating in the ocean.

- [Joao] Marine plastics, it's a global problem.

- [Pedro] We find lots of stuff.

- [Ana] Plastic pollution is really becoming one of the highest pressures ever in the ocean.

This is a silent threat.

- [Narrator] Plastic pollution can impact marine life in two ways.

- [Ana] One for entanglement and ingestion, and the other through chemical toxicity.

- [Annalisa] And it can have long term effects on the population survival and on the physiology of these organisms.

(dolphins chirping) (gentle music) - [Narrator] How impacted is the remote Madeira archipelago by plastic trash?

And how are scientists studying the issue?

(dramatic music) - [Announcer] Major funding for this program was provided by the Batchelor Foundation encouraging people to preserve and protect America's underwater resources.

Additional funding was provided by the Parrot Family Endowment for Environmental Education.

(gentle music) - [Narrator] Madeira.

Nicknamed the pearl of the Atlantic, this Portuguese outpost is located closer to north Africa than mainland Portugal.

Known for its wine and flourishing gardens, whales have also long played an important role on this island of eternal spring.

(bright music) - There was an important whaling period in Madeira.

It operated during about four decades, between 1940 to 1981 when the last whale was killed.

And it was targeted mainly to one species, the sperm whale.

- They're considered to be one of the species that we see all year round.

- [Filipe] They caught about 6,000 animals during that period.

- It stopped because whale products were not needed anymore.

The whale hunters stopped the activity voluntarily.

And then the waters of Madeira became protected.

And this became a sanctuary for whales.

(gentle music) - [Narrator] Today, tourists come to see the whales, and researchers study the animals along the island's southern coast.

- We have deep divers that come fairly close to the coast.

And these deep divers are, for example, sperm whales, pilot whales and beaked whales and even Risso's dolphins.

But also we have more coastal species such as bottlenose dolphins.

- [Narrator] Scientists with MARE-Madeira's marine megafauna group are conducting a variety of studies on the animals that frequent local waters.

- We started in 2016, and we're much interested in the population dynamics of cetaceans, whales and dolphins.

(dolphins chirping) - MARE-Madeira is part of a large institute in Portugal.

At the moment, we are around 40 scientists including Ph.D.

students, technicians, communication people, project managers.

And we have, I think at the moment, 13 to 14 nations represented in our group.

(gentle music) - [Narrator] To understand the presence of plastics in the surrounding waters, and the impacts they are having on whales and dolphins in the area, postdoctoral researcher Annalisa Sambolino conducted net trawls.

- The nets mainly used for microplastic sampling is a manta trawl.

So it's like a net that is able to filter the water and collect samples in the first 20 centimeters of the water column.

And trawling this net during 20 minutes or less for about one mile.

And so we have an idea of how much microplastic you can find in that area.

- [Narrator] Next, items are closely examined under a microscope.

- This sample that we collected, it was quite far from the coast.

It was about two to three miles.

So where we have depth already of about 1,000 meters.

And we found that in the water was all these micro and mesoplastics.

- [Narrator] Particles smaller than five millimeters are considered microplastics.

- After five millimeters, normally they've been called mesoplastics.

And after that, it depends a bit on the study, but it could be up to 25 millimeters, for example.

And then it will be called macro.

And I will just count all the plastic I found, I will annotate which is the color, the type of plastics or whether it is a fragment or a filament.

A film or a fiber, for example.

And normally I will also measure them, and then, it will go for polymer analysis.

- [Narrator] Microplastics are split into two categories, primary and secondary.

Primary microplastics are manufactured to be small for a specific purpose, like microbeads found in personal care products or pellets that will be melted down to create larger plastic items.

- [Annalisa] The secondary microplastics are those particles that they come from the fragmentation and degradation of the bigger pieces of plastics.

They become smaller and smaller while they are in the ocean and they get weathered by the sun, by chemical and physical processes in the ocean.

So what we find here, many times it was these kind of small fragments that were very clear because they already lost all their colors because they come from farther away.

(gentle music) - [Narrator] Knowing that plastics are in the ecosystem, made the experts want to see if squid and pelagic fish, which are fish occurring in the open sea away from the shore or bottom, were feeding on these plastics.

- [Annalisa] Most fishermen here they go out and they fish pelagic fish.

They can sell it in the market.

- [Narrator] These fish are not only popular with Madeirans but are also a food staple of bottlenose dolphins.

- So this is a sample from the digestive system of a mackerel.

And we check what was inside the stomach or the intestine.

Mostly what we find is the microfibers, the synthetic fibers, and these are fibers that mostly come from the clothing, and they just end up in the ocean because of all the washing machine and the wastewater treatment plants are not able to filters all these fibers.

These fibers, they are everywhere.

They are contaminating the air we breathe, they contaminate the water we drink.

So I think it's more like a general problem.

It's not specific only of marine organisms.

- [Narrator] Annalisa also analyzed the muscle tissue of the fish.

- [Annalisa] The muscle, I was keeping it to analyze for phthalates, that is a class of plastic additives that could be absorbed from the plastics they ate.

So the idea was to study both like which plastics they ingest, but also like what is the effect they have in their body.

So which are the chemicals that they absorb in the body after ingesting the plastics.

(gentle music) - [Narrator] Phthalates are a group of widely used chemicals that make plastics more flexible and durable.

They are also found in cosmetics and personal care products.

Phthalates interfere with the body's natural hormones, making them detrimental to human health.

The chemicals have an adverse effect on multiple organ systems, as well as reproductive health and child development.

- They can have an effect in our body, but in also in marine organisms as endocrine disruptors.

One of the most common effects is to affect the fertility of the organism.

So that's why you can have long-term effects on the population survival itself.

In almost all the samples we analyze, we found some concentrations of these phthalates and some microplastics inside digestive systems.

The concentrations were low, they were not like alarming concentrations of course, but it was showing that there is like a chronic exposure of these organisms to both plastics, synthetic particles, and phthalates.

(light music) - [Narrator] When available, Annalisa also analyzed squid, the primary diet of deep-divers like short-finned pilot whales.

- In squids, we found a bit less both of particles and concentration of phthalates.

We think because of the different depth at which they feed.

We think that farther you are going from the coast and less pollution you should find.

But at the end is not really what we found out because the plastics is mainly transport here by ocean currents.

And also like there is an influence from the plastic that is runoff from the island as well.

We saw a difference in the amount of microfibers, for example, that were in the sea.

Especially in the rainy season, you will see a lot more.

And so we imagine that is because there is a runoff from the island itself.

But beside that, we know also that the ocean currents, brings up here a lot of microplastics.

It comes mainly from the Canary Current.

- [Narrator] Knowing plastics were present in the fish and squid that bottlenose dolphins and short-finned pilot whales feed on, Annalisa wanted to know if these top predators were impacted as well.

- [Annalisa] They are the two main resident species here that we can find the most during all the year.

- [Narrator] The researchers conducted minimally invasive biopsies of the animals to collect a small sample of skin and blubber.

- Phthalates, like many other chemical compounds, accumulate in the fat tissues.

And so we knew that if we could find them, it will be in the blubber of the animals.

And we found phthalates, some of them more than others, we analyze six different types.

Especially two of them that we know that are the most dangerous, but they're also the most ubiquitous, we found in almost all the samples.

Most likely, this is an indicator that these chemical compounds are also present in other tissue of the animal.

In bottlenose dolphin, there was one main prevalent type of phthalates that was in there.

And pilot whales are more a deep diving species also had a different profile of contamination.

We think it's a bit dependent on the prey the eat, but also like the habitat where they live.

From the samples we had, the bottlenose dolphin were more affected.

And it will make sense because they stay in this area where there is more concentration of plastics, and they stay closer to the coast as well.

(gentle music) - [Narrator] Sperm whales and short-finned pilot whales are two of the species of toothed whales that can be seen in Madeira year-round.

- Both pilot whales and sperm whales are very social species.

They live in pods.

They can go up to three to four generations living in the same pod.

- And the intelligence that these animals demonstrate, it's incredible.

I think they have a complexity in them that it's absolutely fascinating.

- [Narrator] Recent studies seem to indicate that deep-diving toothed whales, like short-finned pilot and sperm whales, wash up with a higher proportion of plastics in their guts than animals who feed in shallower water.

- For deep divers, we see that they're usually found with like shopping bags, like film-like plastic, within their digestive tracts compared to shallower divers that instead tend to ingest more like fragments of plastics.

And of course, this ingestion of plastic in both cases, lead to problems and either like the diving behavior or the feeding behavior and eventually to death of the species.

- It's a slow death.

It's a horrible death.

(soft music) - [Narrator] Deep-diving toothed whales rely on echolocation to hunt their prey in the dark, deep sea.

- They have this extra sense, they produce a sound, that echoes in an object or a prey and gets back to them.

And, they have this physiologic capability of interpreting that sound, that echo that comes back.

And that is really an incredible adaptation of nature because it allows them to see the environment wherever they are.

- What we were wondering is what if the echos that they're used to receive for like thousands, millions of years from their preys right now are very similar to the echos that started to receive from things that we are putting into the ocean, such as like plastic and especially the fact that there are some species that ingest a lot of quantity of plastic and specific type of plastic.

We decide to look into that on the acoustic point of view.

The main prey item of deep divers such as sperm whales and pilot whales is believed to be deep sea squids.

- Something in the plastic composition must be acoustically similar to the acoustic signature of the real preys of these deep diving species.

(pensive music) - [Narrator] To find out, the researchers set up a preliminary experiment in a large saltwater tank at a facility in the Canary Islands.

- And we collected a subset of different type of plastic that can generally be found in stomachs of stranded species and a sample of natural prey.

- [Narrator] Using an echosounder attached to the wall of the tank, the experts sent out an acoustic signal to bounce off the various plastic and prey items.

- And we listened to that sound coming back, trying to imitate these cetaceans, how they would see those items.

Could they differentiate between a plastic bag and squid?

- [Laura] And what we saw is actually that there are many overlaps of these acoustic signature with natural preys with some type of plastic.

Meaning that possibly the echo that these animals receive back from the plastic is almost the same or like very similar to those that would receive from the natural preys.

- There is something in the plastic signature that makes these really well adapted animals mistake their prey for plastic.

- [Laura] And now that we are seeing this overlap, okay, maybe we continue.

- Probably doing some experiments actually in the ocean, not in the tank.

And maybe use some live prey specimens.

- I think it's very, very interesting like try to link this acoustic world that we cannot really perceive to actually make a sense of what these animals sense and perceive and why things are going bad in that kind of way.

(soft music) - [Narrator] Knowing how big of a problem plastic pollution is in the oceans, MARE-Madeira researchers also assess where and what kinds of trash washes up on the island's shores.

To document seasonal changes, the experts go out every three months during low tide.

- It's to assess what's happening here, what is coming in our waters and what they expected to see in the future is what is the litter will come and stay in our beaches.

(energetic music) - [Narrator] To collect micro sized items, the team sets up five 50-square-centimeter quadrats, 25 meters apart, at the high tide line and sifts the top layer of sand.

The collected items are then taken back to the lab for analysis.

- They already realize there is more common types of plastics who are coming here and what is important to understand what is staying here to us to assess and to provide some planning for the future.

- [Narrator] Larger trash is collected by walking the beach.

- [Silvia] They walk in the line spreading in the beach to see everything that you can collect as a macro litter in the beaches.

And then in the end, you do that square where you do a categorizations of the litter that you collected.

- [Narrator] Items are sorted into different categories, including those that float and those that sink.

Organisms often attach themselves to floating plastics, which can travel long distances in ocean currents.

- They can be invaders in other areas and sometimes the invaders can spread more easily and occupy space for the native ones.

That's why it's important for us to understand from where they are coming and to understand if you need to do some intervention to just, "Okay, you cannot spread here because you will affect directly other communities."

(gentle music) (waves murmuring) - [Narrator] During a long-term monitoring program on biodiversity in 2016, the MARE-Madeira team also came across a previously undescribed type of plastic pollution.

- These are little plastic crusts encrusted to the rocks in the intertidal environment.

We were the first to actually characterize that type of plastic pollutions in the world.

And we believe that those plastic crusts are the result of a combination of things.

First, it's the mechanical action of waves throwing bigger pieces of plastic into the rocks.

Then you have the rocks that have a special texture and a special temperature.

And these plastics, they kind of melt and are encrusted in the rocks.

This is not an exclusive phenomenon in Madeira.

We now know that this problem was already reported in different parts of the world.

- [Narrator] In addition, the research team uses drones to study the accumulations of larger plastic trash.

- They are quite a complimentary methodology.

And they are very good to assess remote areas.

It can cover our larger areas, and it's more fast.

- [Narrator] A drone pilot collects overlapping images taken at the same height that can later be stitched together into one large photomosaic.

This sizable image serves as a contamination map of an area on which trained experts can mark all the trash they can identify.

- For example, this is a bottle.

But if someone is not common to see a rock beach or a sand beach, maybe you'd be, "I don't know if it is a rock or not."

But the trained eye, can understand the difference between the light and the organic shapes, and as you can see, this is a white bottle.

You can easily assess everything and count and create areas and say, "Okay, in 100 kilometer I have five, I have 100 objects."

Then you can assess the quantity and how contaminated is your area or no.

- [Narrator] These drone assessments have many practical applications.

- Where is the area you need to more focus on cleaning or need to be with more human interaction with the beach.

- So we should have a very permanent intervention on those sites because we have there an opportunity to remove those items away from the current.

And so that's why we are increasing our work in the last few years on those sites.

- [Narrator] Since 2020, the regional government has been conducting quarterly surveys and cleanups of the area's shorelines.

- Every three months we go to 10 different locations.

And the remote accumulation site is whenever we can.

What we would expect as most of the population and the activities are on the south part of the island is that most of the items were found here, what our numbers are showing is that there's a big, big difference.

And most of the items get ashore on the north part of the island.

So that proves our idea that we are really influenced by the Northern Gyre Currents.

And so it gives us a view that most of the items were coming from other places.

We are getting here some items from the Caribbean or from North America.

European measures will do nothing about them.

And some of them are from the United States, and I know that it's a big red flag when you know that your litter is polluting somewhere really far away.

And a really important site for nature conservation.

We need to take care of our things where we are because we might be polluting somewhere else that might not have the amount of money, for example, to study or to remove those items.

(light music) - [Narrator] While Madeira is seeing fewer impacts from plastic pollution than mainland Portugal, it is still exceeding international pollution thresholds by 90%.

- So we can say that we are less worse.

(chuckles) Let's call it like this.

So it's not just our problem.

It's an international one.

It's everyone's problem.

- This is not natural.

This is not the normal way as the environment should works.

- Animals have an intrinsic value, and nature has an intrinsic value, and we don't know enough of nature to know what happens if a part of it disappears.

- As much as it's a problem for marine mammals, it is also a problem for us.

We're seeing more in the long-term impact that plastics in general is having on our health as well.

This is a general problem that we have to address like from the source.

(pensive music) - [Narrator] Many challenges remain.

But researchers continue to improve our understanding of the impacts plastic trash is having on our oceans and the whales and dolphins that call it home.

- So I think there were a lot that we did in the last 10 years, but I do believe that there is still a lot to do.

Each time that we answer one question, we have three more questions, so I think it's a never-ending story, but I hope that in 10 years we have responded to a few more questions.

(bright music) - [Announcer] Major funding for this program was provided by the Batchelor Foundation encouraging people to preserve and protect America's underwater resources.

Additional funding was provided by the Parrot Family Endowment for Environmental Education.

(energetic music)