The Enchanting Underwater Sculptures Saving Our Reefs

A pair of white and black striped banner fish float by.

All you can hear is your own methodical inhales and exhales as an unusual site materializes in the water ahead of you. You blink a few times from behind your mask to make sure what you’re seeing is real: a cone-shaped cement structure planted in the sand and covered in…casts of human faces?

Should you make your way to one of Thailand’s most popular dive spots, the island of Koh Tao, this scenario is not so unlikely. You could very well see some of New Heaven Dive School’s artificial reef sculptures while scuba diving and feel, well, some kind of way about them.

At least, that’s what New Heaven’s Artificial Reef Program Director Spencer Arnold was hoping for when he designed the sculptures.

“I really like the idea of people seeing themselves in these ecosystems. Normally when we’re just looking at coral, they’re incredibly simplistic and primitive organisms that we have little empathy for,” Arnold said. “At least, it would seem. Otherwise we would be trying harder to save them.”

Coral reefs are made of tiny invertebrates called polyps that band together to form colonies. Despite looking like plants, they are actually animals, and they have a unique relationship with photosynthetic algae that helps them grow. Hard corals build tough exoskeletons from minerals in the water to protect themselves, and these exoskeletons form the basis of what we know as coral reef habitats.

Even though coral reefs cover less than 0.1% of the Earth’s surface, they are home to over 25% of marine species, according to the Coral Reef Alliance. This fact makes them one of the most biodiverse habitats on the planet.

But coral reefs are in deep trouble these days. Anthropogenic and natural threats have led to the death of about a fifth of the world’s coral from 2015 to 2018. UNESCO scientists predict coral reefs will disappear by 2100 unless we drastically reduce CO2 emissions.

Coral reefs provide value worth an estimated $30 to $170 billion. Without them, everything we know and love could be affected, from the seafood on our plates to our vacations and our friends’ jobs in the tourism sector.

Through building artificial reefs, New Heaven stimulates new coral growth. Because coral reproduces asexually, you can grow new coral from fragments of existing coral knocked off from rough seas or poor anchoring.

Arnold explained, “The artificial reef provides a stable habitat for corals to thrive on. So corals rolling around in the sand — a small coral fragment would die in that dynamic ecosystem. Take that coral dying in the sand and plant it onto a stable surface, that coral can now essentially adapt itself to steady environmental conditions and start thriving.”

The goal is both restoration of current reefs as well as breeding a new generation of hardier corals. The “gardened” coral encrusts the sculpture, grows to maturity, and reproduces, starting a new generation of coral colonies better adapted to withstand the coming changes in the ocean due to climate change.

Creating artificial reefs is not a new idea: humans have been making artificial reefs for centuries, though in the past they have been made of sunken found objects. The “art” of it is a newer trend, however.

Thanks to the intriguing marriage of art and science, there are now artificial reef sculptures all over the world. Artist Jason deCaires Taylor has been designing them for over a decade, including creating the world’s first underwater sculpture park in Grenada, West Indies in 2006.

“The loss of our environment, how our oceans are changing, is such a vital thing that we all need to discuss it, we all need to act upon it immediately,” deCaires Taylor told BBC News. “Creating works about something else just seems arbitrary or pointless when we live in such critical times.”

New Heaven’s Reef Conservation Program [NHRCP] is now testing a newly available technology that could stimulate coral growth on artificial reefs at 3-5x the current rate.

NHRCP has built and installed electrified reefs in their CoralAID site to test the formerly patented Biorock technology against its non-electrified counterparts. They pump a low voltage electrical current (safe for swimmers and marine life) through the structure, which causes minerals suspended in the seawater, such as calcium, magnesium and bicarbonate, to precipitate and harden onto the structure through a process called mineral accretion.

The minerals form a hardened substance not unlike the substrate of natural reefs. Mineral accretion creates chemical and physical conditions that help coral fragments planted on these structures grow faster.

This technology is a promising tool in the marine restorationist’s toolkit, though few around the world have had access to it until now.
Ultimately, the true art and beauty of these artificial reef sculptures is if they’re successful, they will soon be unrecognizable, Arnold explained. Corals will grow over eerie images of human faces underwater, transforming them into images of hope.

Arnold added, “At the end of the day, whether people like the sculptures or not is inconsequential. They’ll still serve as fantastic habitats for coral growth and that’s ultimately the real point of this work in the first place.”