Giant Coral Reef

We just came back from covering Senator Whitehouse's event here in RI, showcasing great energy and environmental leaders.  Coral reefs, we found out there from the experts, play a remarkable role in protection our coast line from storm surge and flooding.  There are many examples where areas protected by sea grass and healthy coral reefs had little or no damage, and no deaths, during major events, unlike other nearby areas that were devastated.

Giant Coral Reef in Protected Area Shows New Signs of Life

By KAREN WEINTRAUBAUG

A giant clam in the Phoenix Islands Protected Area. Credit Craig Cook/Undersea Medical

In 2003, researchers declared Coral Castles dead.

On the floor of a remote island lagoon halfway between Hawaii and Fiji, the giant reef site had been devastated by unusually warm water. Its remains looked like a pile of drab dinner plates tossed into the sea. Research dives in 2009 and 2012 had shown little improvement in the coral colonies.

Then in 2015, a team of marine biologists was stunned and overjoyed to find Coral Castles, genus Acropora, once again teeming with life. But the rebound came with a big question: Could the enormous and presumably still fragile coral survive what would be the hottest year on record?

This month, the Massachusetts-based research team finished a new exploration of the reefs in the secluded Phoenix Islands, a tiny Pacific archipelago, and were thrilled by what they saw. When they splashed out of an inflatable dinghy to examine Coral Castles closely, they were greeted with a vista of bright greens and purples — unmistakable signs of life.

“Everything looked just magnificent,” said Jan Witting, the expedition’s chief scientist and a researcher at Sea Education Association, based in Woods Hole, Mass.

Global climate change is wreaking havoc on corals worldwide. Coral bleaching has caused extensive damage to regions extending from the Great Barrier Reef to the Caribbean and nearly everywhere in between.

“Threats to tropical coral reefs worldwide have escalated to a level that imperils the survival of these complex, diverse and beautiful ecosystems,” Janice M. Lough, an Australian researcher, wrote in a February opinion piece in Nature.

Coral can be severely damaged by rising water temperatures, which cause acidification, as well as by pollution and human activity like tourism, fishing and shipping – prompting some governments to restrict such activities.

If Coral Castles can continue to revive after years of apparent lifelessness, even as water temperatures rise, there might be hope for other reefs with similar damage, said another team member, Randi Rotjan, a research scientist who led and tracked the Phoenix Islands expedition from her base at the New England Aquarium in Boston.

No one actually knows what drives reef resilience or even what a coral reef looks like as it is rebounding. In remote, hard-to-get-to places, our understanding of coral is roughly akin to a doctor’s knowing only what a patient looks like in perfect health and after death, Dr. Rotjan said.

Coral Castles’s revival might be an isolated situation, a fluke in a faraway place. But Dr. Rotjan and her team are on a quest to find out why this coral and other reefs nearby came back to life.

“There’s a recipe book that can be developed out of what we’re learning here,” Dr. Witting said. “You need to make a strong case that this can work before anyone else will try it.”

Divers from the New England Aquarium surveying reefs in the Phoenix Islands Protected Area last September. Credit Craig Cook/Undersea Medical

The lagoon sits in the middle of the largest of the Phoenix Islands, which are inhabited by just a few dozen people, part of the island nation of Kiribati (pronounced KIRA-bas).

The eight-island chain has been listed as a World Heritage Site for its beauty and abundance of wildlife: birds, sea turtles, schools of fish, deepwater sleeper sharks and 200 species of coral. The area has also been a cemetery for sunken ships since voyagers first set out across the Pacific.

To understand the stresses facing corals — from pollution and climate change, for example — researchers would like to isolate each problem. Almost everywhere on Earth, corals must endure climate change and human activity. But not in the 157,626-square-mile Phoenix Islands Protected Area, created by the government in 2008. Shipping lanes skirt the preservation area. Commercial fishing there ceased last year.

Dr. Rotjan, who is also the chief scientist for the area’s conservation trust, said the recent protections might have fostered the coral rebound. The algae that live in corals may also be evolving to cope with warmer temperatures, or hardier coral species may be supplanting others, she said.

In a letter published in Nature earlier this year, another global team of researchers reported a similar coral recovery after they reduced the acidity in three lagoons in the southern Great Barrier Reef, off Queensland, Australia. Carbon emissions increase the acidity of seawater.

“It’s encouraging, because if we do the right things, health might restore in a pretty responsive manner,” said Rebecca Albright, one of the paper’s authors and a postdoctoral scientist at Stanford University.