USGS reveals findings on shrinking coral reefs, speak to solutions for erosion

coral reef
Posted at 1:27 PM, Oct 07, 2022

WEST PALM BEACH, Fla. — Coral reefs are beautiful, colorful and critical in terms of biodiversity, but their longevity is also in question.

"We're at the point now where most reefs around the world have seen up to 50% declines in the amounts of living coral," Lauren Toth, a U.S. Geological Survey Research Physical Scientist, said.

Toth said after thousands of years of growth or stability, 85% of reefs in the Florida Keys are now shrinking because of disease, temperature swings and storms, according to new findings by the U.S. Geological Survey.

"The changes we've seen over the last 50 years in the Florida Keys really are reflective of what we've seen happen on reefs globally," Toth said. "They're currently eroding at a rate that some parts of the reef could disappear in several hundred years, which seems like a lot of time, but that's a lot of structure that's being lost."

The loss Toth described puts coastal residents and property at greater risk during storms.

Curt Storlazz with the U.S. Geological Survey's Pacific Coastal and Marine Science Center explained how reefs lessen the impact of a hurricane.

"It causes waves to break, and when waves break, they dissipate energy, so wave height goes down," he said. "What we showed is coral reefs across the U.S. protect $1.8 billion in infrastructure and economic activity annually and over 18,000 people."

Storlazzi said reefs can break up 97% of wave energy and cited Hurricane Fiona that slammed Puerto Rico in September. He said without the natural protection of reefs, the storm that reportedly killed as many as 25 people could have been much worse.

"We have no time to waste," Andrew Baker, a professor with the Department of Marine Biology and Ecology at the University of Miami's Rosenstiel School of Marine, Atmospheric, and Earth Science, said. "We need this coastal protection now."

Baker's team is engineering hybrid reefs using forms of concrete. They use wave tanks to test the reefs in simulated storm forces.

Baker said the goal is to create tougher structures that thrive in concert with natural reefs. The project is backed by grant money from an arm of the U.S. Department of Defense.

"I think it's a real seal of approval that this approach is worth exploring," Baker said. "It allows us to think big and try a whole bunch of different methods to try to build more resilient reefs as quickly as possible.

Toth said if some of the coral reef restoration efforts that are now underway reach their goals, reef growth can be restored to levels we have not seen in 7,000 years.