Sustainable Fisheries through Advances in Aquaculture: Aquaculture Innovator - Yamamoto Toshimasa

"RISING"

"Sustainable Fisheries through Advances in Aquaculture"
Aquaculture Innovator - Yamamoto Toshimasa

A saltwater aquaculture farm.

Fish are farmed and fed within cages floating on the sea surface.

As an island nation, over 90% of Japan's aquaculture

is conducted in this way,

including bream, yellowtail and other fish varieties

common in Japanese food.

But since the 1960s,

global fish consumption per capita has more than doubled.

And with fisheries pushed to their limit,

2013 saw marine aquaculture

overtake traditional wild capture

as a source of fish for human consumption.

But uneaten feed and fish feces from aquafarms

have been identified as a cause of harmful algal blooms,

while mariculture installations are also vulnerable

to extreme events like typhoons and tsunamis.

In the hills of Okayama,

on the west of the Japanese archipelago,

is Okayama University of Science,

home of the Animal Life Education Center.

Here, we find someone focused on tackling the challenges

faced by aquaculture.

Drat! Got away again.

Professor Yamamoto Toshimasa is a veteran of research in the field.

Nice and fat.

This one's probably about three kilos.

Looks tasty.

His lab uses a closed-loop system

to produce over two tons per year of usually marine

dwelling fish like these hata grouper.

Active organic filters containing bacteria

are used to cleanse the water for repeated reuse.

Most closed-loop aquaculture sees 5% of water

replaced each day,

but in Yamamoto's lab, this is reduced to just 0.1%,

making the approach ideal even for inland installations.

Our aim is aquaculture you can do anywhere,

wherever you go, any desert, any mountaintop.

The first secret is the type of water they use.

Developed by Yamamoto himself,

it's easier to maintain and longer-lasting than seawater.

And that's not the only advantage.

450 kilometers from Okayama,

near the foot of Mt. Fuji, is Numazu, Shizuoka Prefecture.

The home of one of Japan's most productive fishing fleets,

it also attracts numerous tourists in search of the freshest fish.

This local sushi restaurant receives a fish delivery from Yamamoto.

These hata are fantastic.

Nice and lean, and as fresh as it gets.

I'm sure they'll taste great.

Hata grouper! Fresh today!

Order your freshly cut grouper!

Hata is actually a premium fish seldom landed in Numazu.

Here you are.

But what will the diners make of this mountain-raised fish?

The texture's great.

It was nice and firm with a consistent texture all the way through.

I've never had hata before.

It was really good.

So, this plump hata grouper was raised within Yamamoto's lab.

Studies have shown that hata farmed using Yamamoto's method

grow 1.6 times faster

than those farmed onshore in seawater.

The reason is Yamamoto's specially developed water.

This isn't seawater and it's not freshwater.

It's developed in our lab

to provide the optimal environment.

What is it that sets this water apart from

both seawater and freshwater?

The tank in which these carp are swimming contains freshwater.

This is what we use to make our optimal water.

This powder combines the base minerals from seawater

that are essential to marine fish survival.

Next Yamamoto transfers two sea bream to the same tank.

These marine fish can't survive in freshwater.

But in just a few minutes,

they are happily swimming alongside the carp.

Marine and freshwater fish need specific minerals to survive.

The secret to whether or not they'll be able to survive

is actually in the balance of sodium, potassium and calcium.

So while seawater contains some 60 different substances,

the truth is that fish only really need three of those.

Most of them seem to be superfluous.

Keeping mineral content to the bare essentials means that

this water has a salt concentration of only around 1%.

But how does that help fish grow faster?

Fishes' own cells also have a salt concentration

of around 1% compared with 3.5%

in the seawater around them.

This results in the loss of water due to osmotic pressure.

To replace these lost fluids,

they constantly take in water,

removing excess salt via the gills and in hyperosmotic urine.

But this process requires energy.

Because Yamamoto's water has a similar salt concentration

to the fishes' own cells,

the need to expend this energy is eliminated,

and this is thought to be the root of the faster growth.

Yamamoto has long been leveraging these benefits

for the terrestrial aquaculture of marine fish.

In 2011, he succeeded in farming "fugu" pufferfish,

a highly prized delicacy in Japan.

Marketed under the university's name,

it commanded high prices

and was sold as freshly cut premium sashimi.

Another Japanese favorite is "unagi."

These freshwater eels migrate to the sea to spawn,

but dwindling stocks have seen prices skyrocket.

In 2012, Yamamoto managed to farm this species

which is classified as endangered.

To date, he's succeeded in the terrestrial aquaculture

of 10 species of sea creature.

His previous career was in the metal industry

where he researched the impact of factory effluent on fish populations.

Then, at the age of 31,

he pursued an interest in fish to set up a home aquarium stockist.

In 2001, he was invited to lead a new course

teaching aquarium staff at a vocational college

affiliated to Okayama University of Science.

But the college was located in the hills some distance from the sea.

I visited the proposed site,

and there it was in the hills with nothing for miles around.

I asked where we'd get our seawater and they said that

we could just buy in artificial stuff.

But the cost of artificial seawater went way

beyond the budget available to Yamamoto

making trips to fetch seawater himself a daily necessity.

He used a pump to fill a tanker and drive back into the hills.

It was tough doing this every day

and taking it back to the hills.

His classes called for as much as five tons of seawater per week.

And this constant demand was further driven

by the need for seawater to culture the plankton used as fish feed.

Then one day, a student asked Yamamoto

why plankton couldn't be cultured in freshwater.

He suggested culturing marine plankton.

The one we use is called Brachionus plicatilis-in freshwater,

which is the same thing as saying

"let's throw this tuna in a lake."

The first time I just thought, what's he on about?

But then he asked a second and a third time.

And it was that idea from a student

that provided the spark for Yamamoto's water.

We visit his former student to hear more about the background to this story.

After graduation, Takahashi Nobuhiro moved back to his hometown

where he now runs a tropical aquarium retailer.

As a student, he realized that culturing the marine plankton

used for fish feed in freshwater

could ease the burden of procuring seawater.

I tried culturing Brachionus in freshwater

and somehow it worked.

I told Yamamoto-sensei about what I thought was my successful attempt,

but when we looked closer and measured the salinity,

there was still a small amount of seawater mixed in with the water I used,

so it wasn't 100% freshwater.

Seawater residue on the unwashed tank

had resulted in a minuscule salt concentration.

But for some reason, the plankton grew

even more vigorously than in seawater,

and that gave Yamamoto an idea.

I thought, hang on,

if we can get these results with 1/10 seawater,

maybe our water worries when it came to culturing fish

or culturing plankton were over,

and perhaps we didn't need seawater after all.

He really helped shatter the received wisdom.

Yamamoto began to reexamine the composition of seawater.

And after a year of experiments,

he discovered that a mineral balance of 29 parts sodium

to one part each of potassium and calcium

created the ideal conditions for fish.

By 2006, he'd perfected his own optimal water.

Having finally found a way to culture marine fish absolutely anywhere,

he realized its potential applications in land-locked countries.

Ulaanbaatar is the capital of the central Asian nation of Mongolia.

It's also home to an aquaculture installation in a converted cinema.

In 2019, Yamamoto partnered with the local arm

of a Japanese construction firm to start farming hata grouper here.

And with Yamamoto unable to travel in person due to the pandemic,

since 2020, the facility has been operated solely

by local staff.

Hi there! How are you?

Aquaculturist, Battorj Amartuvshin

previously studied under Yamamoto as an exchange student in Japan.

He provides daily updates on the state of the installation in Ulaanbaatar.

Due to the pandemic,

the border with China was shut down and goods couldn't get in.

We had real issues with the late arrival of water

testing kits and fish feed.

I was so stressed that some nights I couldn't sleep.

And having kept meticulous track of the data

from Mongolia over the last two years,

Yamamoto tells his colleagues how well they are doing.

Imagine if we packed up today and shipped all the fish we have there.

What do you think the total mass of fish would be?

Maybe about 700...

No, 800 kilos?

Nope. It's 1.23 tons.

It's amazing.

You're doing a great job, Amar!

Thanks.

Among the hata raised by Amartuvshin

is this seven-kilo specimen,

bigger than anything raised so far in Okayama.

To spread the word about the freshness and flavor of the cultured fish,

they launch tastings at restaurants in Ulaanbaatar.

This French restaurant serves a colorful hata and tomato soup,

along with succulent hata steaks

that perfectly showcase the quality of Amartuvshin's produce.

It's very good.

It's amazing they can raise marine fish

in a land-locked country like Mongolia.

And Amartuvshin and the team continue to work towards the day

when fish might become a staple of every day Mongolian home cooking.

I feel like I've got the hang of aquaculture now,

so I'd like to try raising some different kinds of fish.

I'm so grateful to the fish for surviving the local climate for us.

And Yamamoto has actually been leveraging his approach

to support developing nations since 2013.

In conjunction with JICA,

he's conducted successful trials culturing river shrimp in Cambodia.

And moving forward, there are hopes that expanded production

could be a big help for impoverished inland farmers.

Our water makes aquaculture possible

in any part of any country around the world.

We've had requests for assistance from many countries,

so beyond continuing our research,

I want to make those partnerships a reality.

December 2021,

and Yamamoto makes the 680-kilometer journey

from Okayama to Fukushima Prefecture.

It's the region of the nuclear disaster

triggered by the Great East Japan Earthquake and Tsunami of 2011,

and the ramifications for local fisheries continue to this day.

As of February 2022,

restrictions on most marine fish shipments have been lifted

after a majority of local species

cleared Japan's legal limits for radiation.

But coastal fishing has been slow to recommence

and consumer fears persist.

This supermarket chain has 17 stores

across Fukushima Prefecture.

But with local supplies limited,

the seafood corner is stocked entirely with fish

caught elsewhere in Japan or overseas.

Even here, Fukushima-caught fish is a very rare sight.

Company executive, Ito Yoku has been searching for a solution.

Ever since the nuclear disaster,

customers' health and safety concerns et cetera

have made it hard to sell local fish.

Our business grew out of fish retail,

and because of our heritage selling local fish,

it really is highly regrettable

that we're currently unable to do that.

And local customers feel the same.

It's a real pity.

There's all sorts of nice local fish.

Fukushima fish really is good,

but of course...

I've never had it.

You haven't, have you? It's hard to find.

Ito hit upon the idea of aquaculture,

to farm and sell another Japanese favorite,

sockeye salmon, right here in Fukushima.

Fillets for cooking will be over here.

But we also want to sell fish to be eaten raw

to showcase the strengths of aquaculture in terms of safety,

freshness and flavor.

And cultured fish are also free from parasites,

so we also hope to present the fish sliced for sashimi.

Sockeye salmon is known for its red color and fine flavor,

with most examples caught in the wild.

But here, they've recently completed an aquaculture installation

on the company's premises,

and the drive to farm salmon using Yamamoto's approach

is now underway.

It's a joint effort between this local supermarket chain,

Yamamoto's lab, and a major telecommunications firm.

The high-tech setup will use digital monitoring technology.

We'll be mixing our water inside this tank.

Pretty nice setup, huh?

All that's left to do is add the fish.

I'm looking forward to the new year.

Supermarket employee Akiyama Yukihito

undergoes training with Yamamoto at his lab in Okayama

including guidance on how to feed the salmon.

Salmon won't eat feed that's sunk to the bottom.

You need to scatter it correctly.

I've heard that sockeye salmon

can be quite a difficult fish to raise.

Migrating to the sea after hatching in the river,

sockeye salmon are famously ill-suited to aquaculture,

and tales of successful cultivation are rare.

January 2022,

and a delivery of 1,000 sockeye salmon

fry arrives in the prefectural capital.

Good morning.

Hey there. Happy New Year.

With the tanks already prepped with Yamamoto's water,

all that remains is to add the salmon fry.

How is it?

Is it dissolving properly?

Yes.

But while everything had seemed to be in order...

Let's check the temperature in the tanker.

6.5 degrees? That cold?

Akiyama-san, what's the water temp in there?

What, inside?

12 degrees.

12 degrees?!

Oh no, this is too cold.

We can't just put them in like this.

The shock will kill them.

The long journey through cold weather

has lowered the temperature in the shipping tank

significantly below that in the indoor installation.

They quickly start switching buckets of water between the tanks

to bring the temperatures closer.

It's exactly 10 degrees.

Within two degrees.

Let's do it.

After an hour of teamwork,

the temperature difference is finally in check...

And at last they can transfer the fry to the indoor tanks.

It's better if you lower the bucket in.

Don't just tip them out.

That's it. That's the way.

Bucket by bucket, they transfer the salmon fry.

And at long last,

the fish are comfortably ensconced in Yamamoto's water.

It's always good to get the fish into a new installation.

Yep, it's a good feeling.

This is great.

I'm really happy that we've finally made it this far.

I think there's a lot of anticipation for this across Fukushima,

so I can't wait to deliver safe, healthy local fish.

It's hoped that these salmon might be ready for market in

as little as one year,

and Yamamoto will be supporting his partners

every step of the way

to make Fukushima salmon a reality.

We're very lucky that our aquaculture technology

is suitable for use anywhere.

If this terrestrial aquaculture can be used in struggling regions,

then at the end of the day,

that's our ultimate goal.