Can Swarming Robots and Cloud Umbrellas Help Save Coral Reefs?

As reefs continue dying off, scientists have started to think more boldly about how to protect them

The world’s reefs are fading fast.
The world’s reefs are fading fast. Photo courtesy of Flickr user Eric Burgers

A little more than a year ago, Australian scientist Roger Bradbury declared that it was game over for the world’s coral reefs. He referred to them as “zombie ecosystems” that were neither dead nor really alive, and “on a trajectory to collapse within a human generation.” He went so far as to suggest that it’s now a waste of time and money to try to protect coral reefs. Instead, he argued, scientists should focus on figuring out what can replace them.

His piece in the New York Times provoked a lot of feedback, much of it suggesting that he had been far too dire, that while the situation may be grim, it’s not hopeless and that the last thing scientists should do is to stop looking for ways to keep them alive.

Now, as we slide into the last weeks of summer, is Bradbury seeming more prescient? Is it clearer that we’re a year closer to the demise of one of more diverse and vibrant ecosystems the Earth has seen? Most experts would tell you no, that they’re not ready to concede coral reefs are going the way of dinosaurs. But they haven’t had much reason to be more hopeful, either.

A study from Stanford University, published last month, concluded that if carbon emissions stay near where they are now, there will, by the end of the century, be no water left on Earth that has the chemical makeup to support coral growth. The ocean will simply be too acidic.

Another research paper, published in the journal Current Biology earlier this week, suggests that without serious action on climate change, reefs in the Caribbean will likely stop growing and start to break down within the next 20 to 30 years. They’ll basically wear away. An extensive survey is being done in the Caribbean this summer to determine how much of its coral reefs has already been lost. Some estimates are as high as 80 percent.

Clouds as umbrellas

It’s reached the point where some scientists think they can no longer rely on natural forces to keep reefs alive; instead they’re developing ways to use technology to save them. A team of British researchers, for instance, believes geoengineering is called for. Their idea is to turn clouds into umbrellas that would protect reefs by bouncing more sunlight back into space.

They would do this by spraying tiny droplets of seawater up into the clouds above the reefs, which would have the effect of making the clouds last longer and cause their tops to brighten and reflect more sunlight. That should lower the water temperature and slow any bleaching of the coral down below.

Geoengineering makes a lot of people nervous because once humans starts manipulating nature on that large a scale, it’s nearly impossible to foresee all of the possible ripple effects. But they could be minimized in this case because the cloud spraying would be targeted to skies only above reefs. That said, even its boosters don’t see this as a long-term solution; at best it buys some time.

Robots that work like ants

Another group of scientists, this one based at Heriot-Watt University in Scotland, is thinking even more boldly. Their idea is to set loose swarms of small robots on dying reefs and have them transplant healthy coral into places where it’s needed. Each robot would have a video camera, along with the ability to process images, and basic tools, such as scoops and “hands” that can grab the coral.

Clever, but also quite challenging. The robots, called coralbots, would need to learn to identify healthy coral and distinguish it from everything else down there. And they would need to be able to navigate their way around the ocean bottom and keep from running into other obstacles and, God forbid, healthy coral.

A key to this approach is how successful the scientists are at programming the robots with “swarm intelligence.” They would work together like ants or bees to perform complex tasks, with different robots having different roles. One might know how to spot places where coral can be planted; another might focus solely on planting.

But it could be a while before we find out if swarming robots is an answer for saving reefs. The researchers hoped to raise about $100,000 on Kickstarter, but weren’t able to reach their goal.

One piece of technology that is functional, however, is the device that’s performing the Caribbean coral reef survey mentioned above. Custom-designed lenses on three camera bodies, mounted at the end of a six-foot pole and propelled by a motorized sled, are capturing amazing 360-degree images of life on the ocean floor. See for yourself.

Sea stories

Here are more recent developments in the world of coral reefs, ocean life and beaches:

  • Just beware of crevasse-seeking fish: CSIRO, Australia’s national science agency, has helped develop the first sunscreen filters that mimic the sun protection used by corals on the Great Barrier Reef. But you may have to wait a bit to take advantage of the Reef’s special powers. The filters, which are resistant to both UVA and UVB rays, may not be incorporated into commercial sunscreens for another five years.
  • Where fish pray never to be caught: Earlier this month an artificial reef more than 200 feet long and designed to look like a rosary was lowered into the sea off the coast of Sto. Domingo in the Phillipines. In addition to becoming a home for sea life, the rosary reef was created with the hope that it will become a tourist attraction.
  • Hard to get past the idea of glass in your trunks: Meanwhile, back on the beaches, pulverized glass may begin replacing actual sand. In Florida’s Broward County, officials are considering using finely-crushed glass to help fill in sections of beaches where sand has eroded.
  • The bad old days: Scientists at the Scripps Institution of Oceanography in San Diego say that the last time Earth was a “greenhouse world”–when the planet had very high levels of greenhouse gases 50 million years ago–it had few coral reefs, tropical water that felt like a hot bath and a paucity of sharks, tuna, whales and seals.
  • Finally, we get jet packs, and now this?: A state agency in Hawaii has begun a review of the use of water-powered jet packs. Seems that the devices, which have become popular among tourists wanting to launch themselves over the ocean, may be doing damage to coral reefs.

Video bonus: Take a breather and see what’s going on at the bottom of the sea. Check out NOAA’s live-streaming video camera.

Video bonus bonus: See how statues are being turned into a man-made reef off the coast of Mexico.

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