Scientists have developed a gel that improved coral larvae settlement by up to 20 times.
Due to ocean warming as a result of climate change, these underwater ecosystems are severely threatened. Scientists working on coral reef restoration have struggled to get coral larvae to settle on degraded reefs or to attach to human-created structures that might not “smell” like home to the larvae.
However, researchers at UC San Diego’s Scripps Institution of Oceanography and Jacobs School of Engineering created a new gel, called “SNAP-X,” which slowly releases some of coral larvae’s favorite “smells.”
Daniel Wangpraseurt, the study’s senior author and a marine biologist at Scripps, said:
“Coral are animals, and their larvae are selective about where they are going to attach because once they do, they’re stuck there. With SNAP-X, we created a material that releases chemical cues that tell coral larvae this is a good place to live.”
The research, published this week in Trends in Biotechnology, was conducted with funding from the US Defense Advanced Research Projects Agency’s Reefense program, which aimed to develop self-healing, hybrid biological and engineered reef-mimicking structures for coastal protection.
Coral reefs are severely threatened by ocean warming caused by climate change. They are projected to decline by 70-90% at 1.5 degrees Celsius (2.7 degrees Fahrenheit) of warming relative to preindustrial times, and by 99% at 2°C (3.6°F). The decline of coral reefs, with their kaleidoscopic beauty and estimated $375 billion in economic value, is something the Coral Reef Ecophysiology and Engineering Lab at Scripps are working tirelessly to prevent.
Wangpraseurt added:
“I’m over hearing that corals are dying — I’m more interested in what we can do about it. My lab’s approach is to combine marine biology with physics and bioengineering to come up with new solutions.”
Scientists have long known that certain types of crusty algae, known as crustose coralline algae, release chemicals that encourage baby corals to attach to surfaces. However, translating this knowledge into practical solutions to boost coral settlement had remained elusive.
Wangpraseurt and his lab wanted to develop a substance that could deliver these chemical cues over an extended period of time in the ocean to accelerate reef recovery efforts.
Samapti Kundu, a postdoctoral researcher at Scripps who worked on the project during her time at UC San Diego’s Department of Chemical and Nano Engineering, and the study’s first author, said:
“If you just throw these chemical cues in the ocean they dissipate very quickly, making it hard for coral larvae to find their source. We needed to develop something like an extended release drug delivery system that would slowly release these settlement cues in the ocean.”
