Each “ark” can shelter around 400 fish. Photo: Coralarks.org
Ty Roach says most reef restoration projects fail within three years, and even successful ones can be wiped out by a single marine heat wave. A molecular biologist and coral reef ecologist, Roach is moving from academia to the private sector with technology he believes could be a breakthrough for rebuilding reefs.
Roach is the CEO of Coral Reef Arks, a company developing spherical structures to restore reefs. The idea grew out of research he began during his PhD. He says, unlike many restoration efforts that start with a solution and then test its effectiveness, his team spent decades studying how viruses and bacteria affect reefs, and engineered a design meant to create the right balance from the start.
Roach’s team says the spherical design has key advantages: they’re movable and adaptable. Each sphere, called an “ark,” is up to 10 feet wide and suspended 30 feet above the seafloor in 60 feet of water. This mid-water placement helps reduce bacterial and viral threats while allowing the structures to be raised or lowered to avoid heat and excess sunlight, reducing the risk of coral bleaching during marine heat events.
“If you plant corals back into the environment that they died in, the likelihood that they (survive for) a long period of time is really low,” Roach told me. “If you plant corals back on a degraded reef, it still has all these positive feedback loops that are leading to coral mortality. And if you put corals back on the (ocean floor), they’re there forever. If a heat wave comes through, everything’s demolished.”
“We’ve engineered the arks in a way that we can move them both vertically, up and down through the water column, but we can also transport them,” added Roach. “If a site becomes degraded, let’s say you suddenly have an algae bloom or nutrient runoff input, we can pick these up and move them. The idea of getting things off the bottom isn’t totally novel, but the scale at which we’re doing it is definitely unprecedented.”
Roach says data backs up the design. Compared with traditional restoration, the arks have doubled coral survival rates, boosted growth, reduced biofouling, improved microbial balance and water quality, and supported more diverse species. They also attract marine life, as each ark shelters about 400 fish.
They currently have structures deployed in Puerto Rico, Curaçao, Saudi Arabia, the United States, and Madagascar. In Saudi Arabia, the arks are part of university research testing probiotics on corals. Roach declined to disclose the cost of the product.
Evan Orellana, a marine biologist and Surfrider Foundation’s regional manager for Florida and Puerto Rico, says several factors determine whether a coral restoration product works. These include attachment success – how well coral larvae settle and grow – along with the size of gaps in the structure, which should provide shelter for reef fish without inviting too many mid-level predators. Placement also matters, as the spot where a reef once existed isn’t always the best place to start a new one.
Orellana warns that not every artificial reef project is beneficial.
“There is a lot of greenwashing you have to be careful with,” said Orellana. “Good intentions don’t always make a great project. I see artificial reefs popping up for the sake of art or just saying you have a reef in a place where people can access it, but it might not do well in terms of species success. There is always a trade-off. Is it an educational tool for the public to view, or is it actually going to be a viable reef in the long run?”
The spheres are movable, which is a big advantage in the design. Photo: Coralarks.org
Roach is confident his team has accounted for these factors to create a product that works. The designs are open-source, but he says they would be difficult to replicate without the expertise of what he calls the best scientific team in the world for reef restoration.
“We haven’t patented (our structures) intentionally,” said Roach. “We want to keep it relatively democratized. If there are people who can come up with a way to do this that is scientifically grounded, then they can move forward with it.”
“But we have quite a few little trade secrets up our sleeves,” Roach added. “There are some things I can’t share on the material science side of things – these aren’t just random balls that we decided to throw out in the ocean.”
After testing several materials, Roach says the latest models use polylactic acid, a biodegradable compound designed to last about 25 years in the ocean – enough time for coral rock to form and replace the structure. The team can engineer versions to last up to 100 years if needed, but Roach notes they are still refining the balance of building a structure durable enough for corals to take hold without adding unnecessary plastics to the ocean.
While Coral Reef Arks is still in its early stages, Roach is confident that if anyone has the answer to coral reef restoration, it’s him and his team.
“I probably understand the fundamentals of what makes a reef work and what makes a reef healthy or unhealthy, at least as good as anyone else in the world, if not better,” said Roach. “(Our structures provide) all the things that you would want out of a reef, if you’re really looking for the ecological services that reefs provide to surrounding communities.”