Narrator: In Kalymnos, Greece,
divers have long profited from one of
the ocean's natural treasures: sea sponges.
You can pick up a synthetic sponge
for just a couple of dollars.
But a single sea sponge
hand-harvested from the Mediterranean Sea floor
could set you back $30.
Harvesting these sponges is dangerous work,
and the risks don't guarantee big rewards.
Sponges used to be plentiful in the Mediterranean,
but these days they're hard to find.
And it's making this already difficult job harder.
So what's happening to the sponges here?
And is this what's making them so expensive?
Synthetic sponges, like the ones commonly used
to wash dishes, are cheap.
And that makes them popular.
But natural sea sponges have been used for centuries.
And they're still essential for pottery, painting,
and even as a surgical tool.
But to get your hands on a sponge like this,
a diver first had to hand-harvest it from the seafloor.
High-quality commercial sea sponges
are found in select regions,
including off the coast of Florida and the Caribbean Sea.
The most valuable ones are largely found here,
in the Mediterranean.
But they're not so easy to come by.
And it means the dangerous effort to find them
isn't always worthwhile.
One of the most dangerous parts of harvesting sponges
happens at the end of a dive.
Although it's less common now,
the most common injury divers face
is decompression sickness.
This happens when divers transfer
from a high-pressure environment
to a low-pressure environment too quickly.
Nitrogen builds up in a diver's body
as they go deeper underwater,
and the body needs time to release this nitrogen
before reaching the surface.
Otherwise, divers risk hurting parts of their body,
or worse.
Narrator: Not only is this one of the biggest risks,
but it's also more time-consuming than the dive itself.
The time it takes to resurface
depends on how deep a diver swims.
A diver might only spend 30 minutes diving at 50 meters,
but they could spend between one and two hours
just returning to the surface safely.
Narrator: It's becoming crucial for divers
to fish in deeper waters,
where more valuable sponge species can be easier to find.
But diving deeper also means
a diver has limited time to harvest.
Otherwise, too much time is lost to resurfacing
and resting between dives.
Despite the little time they have,
extracting the sponges isn't a quick or simple task.
At times, divers must grab hold of a sponge
with both hands, using their force
and a bit of wiggling side to side to extract one.
It's important that they leave enough sponge substrate
attached to the seabed.
That way, the sponge has the potential to regrow
and the population can be sustained.
Another hurdle divers face
is how many sponges they can harvest.
In shallow waters, divers can harvest
only as many sponges as they can carry.
Typically, a diver will carry
about three to four nets' worth of sponges,
or about 8 kilograms, to the surface
before going back down to search for more.
But there's no guarantee a diver
will find that many sponges.
Today especially, there's a good chance they'll return
with fewer sponges than they hoped for.
Narrator: There are likely a few factors
causing this decline.
Narrator: Antonis Kampourakis spent 50 years
diving for sponges.
He believes the climate crisis
is one major cause of the declining population.
The other main issues are likely waste and disease.
Narrator: Sponges used to be known as "soft gold" in Greece.
They thrived in these warm waters,
which is why the Greek islands, and especially Kalymnos,
have historically been a center for sponge fishing.
But the dangerous nature of this work
and the lack of sponges in the sea
make it difficult to find divers who want to do the job.
Compared to the hundreds in the '60s,
only about 30 to 40 people
still dive for sponges in Kalymnos today.
And this is actually one of the reasons
the prices of some sponges have gotten so high.
Because fewer people dive for the sponges here,
and because the ones that are left are difficult to find,
the sponges have more time to grow.
And this means the ones divers do find are often bigger,
which makes them more valuable.
At a separate processing facility,
producers clean batches of the extracted sponges
to remove any remaining black residue from the sea.
A worker then trims each sponge one by one.
Although bigger sponges are worth more,
workers often cut them down.
This makes a sponge easier to clean and bathe with
and naturally more marketable.
Nikolas Makriplis processes five sponge species
from the Mediterranean.
Sponges from this region are desirable
for their durability and softness.
Narrator: Fino is one of the most coveted types he sells.
A single 12-centimeter sponge of this species
can retail for $30.
Narrator: Higher prices mean a better return
for divers and merchants like Nikolas.
But with fewer sponges to find, the future of an industry
that once carried the island of Kalymnos
has a major hurdle to face.