by FORT LAUDERDALE, Fla. (AP) — Researchers in South Florida trying to prevent predatory fish from eating lab-grown coral are using biodegradable straws in an effort to create what some call a rainforest restore the sea.
Scientists around the world have been working for years to address the decline in coral reef populations. Just last summer, reef rescue groups in South Florida and the Florida Keys were trying to save corals from rising ocean temperatures. As well as working to keep existing corals alive, researchers are growing new corals in laboratories and then placing them in the ocean.
But protecting the underwater ecosystem that holds up to 25% of all marine species is not easy. Even more challenging is to ensure that coral grown in a laboratory and placed in the ocean does not become expensive fish food.
Marine researcher Kyle Pisano said one problem is that predators like parrotfish try to attack and destroy the newly transplanted coral in areas like South Florida, leaving them with a 40% survival rate. With projects calling for thousands of corals to be planted in the next year and thousands of corals to be planted in the next decade, the losses add up when pieces of coral can cost more than $100 each.
Pisano and his partner, Kirk Dotson, developed the Coral Fort, claiming that the small biodegradable cage made in conjunction with drinking straws increases the survival rate of transplanted coral to over 90%.
“Parrot fish on the reef really, really enjoy biting newly transplanted corals,” said Pisano. “They throw it like popcorn.”
Fortunately the fish eventually lose interest in the coral as it matures, but scientists must protect the coral in the meantime. Stainless steel and PVC pipe barriers have been set up around transplanted corals in the past, but these barriers needed to be cleaned of algae growth and eventually removed.
Pisano had the idea of creating a protective barrier that would eventually dissolve, eliminating the need to maintain or remove it. He began experimenting offshore with biodegradable coral cages as part of a master’s degree program at Nova Southeastern University. He used a substance called polyhydroxyalkanoate, a biopolymer derived from the fermentation of canola oil. PHA biodegrades in the ocean, leaving only water and carbon dioxide. Its findings were published last year.
The coral cage consists of a limestone disc surrounded by eight vertical pade brand drinking straws, made by Atlanta-based WinCup Inc. generally want to stand themselves facing down to eat.
Dotson, a retired aerospace engineer, met Pisano through his professor at Nova Southeastern, and the two founded Reef Fortify Inc. to further develop and market the patent-pending Coral Fort. The first batch of cages were priced at $12 each, but Pisano and Dotson believe that could change as production increases.
Early prototypes of the cage made from standard pad drinking straws were able to protect the coral for about two months before it dissolved in the ocean, but that was not long enough to combat the parrot fish’s welfare. When Pisano and Dotson reached out for help, the company assured them that it could make almost any custom shape out of its biodegradable PHA material.
“But it turns out that the boba straws, right out of the box, work fine,” Dotson said.
Boba straws are wider and thicker than normal drinking straws. They are used for a tea drink that includes tapioca balls at the bottom of the cup. For Pisano and Dotson, that extra thickness means the straws don’t last long enough to protect the growing coral before they disappear harmlessly.
Reef Fortify hopes to work with reef restoration projects around the world. The Coral Forts are already being used by researchers at Nova Southeastern and the University of Miami, as well as the Hawaii Division of Aquatic Resources.
Rich Karp, a coral researcher at the University of Miami, said they have been using the Coral Forts for about a month. He pointed out that it takes a lot of time and effort to do any work underwater, so having a protective cage that dissolves when it is no longer needed cuts their work in half.
“Simply caging corals and then removing the cages later, that’s twice the amount of work, twice the amount of bottom time,” said Karp. “And it’s not really scalable.”
Experts say coral reefs are a significant part of the oceanic ecosystem. They occupy less than 1% of the world’s oceans but provide food and shelter for nearly 25 percent of sea life. Coral reefs also help protect people and their homes along the coast from storm surges during hurricanes.
