Global ocean warming accelerates threats to coral reefs, need to remove CO2

In How fast are the oceans warming?, L. Cheng, J. Abraham, Z. Hausfather, & K. Trenberth, 2019, Science, 363:128-129, reassess global ocean temperature data and finds that the heat content of the ocean is increasing considerably faster than had been realized, and at an accelerating rate over the last 15 years.

Source: NY Times – and Environment

The world passed the temperature tipping point for mass coral bleaching in the 1980s (T. J. Goreau, & R. L. Hayes, 1994, Coral bleaching and ocean “hot spots”, AMBIO, 23: 176-180), and as predicted 30 years ago coral bleaching episodes have gotten more frequent and severe to the point that we have now lost most of the world’s corals (T. J. F. Goreau, R. L. Hayes, & E. Williams, 2018, We Have Already Exceeded the Upper Temperature Limit for Coral Reef Ecosystems, Which are Dying at Today’s CO2 Levels, GCRA White Paper, UN Framework Convention on Climate Change Talanoa Dialog).

At the time that we passed the bleaching tipping point the rate of shallow ocean warming on this scale (compared to the 2006-2015 average) was only around -15, compared to +5 now!

The clear future prognosis is for greatly increased future surface temperatures and mass bleaching heat stroke events to steadily wipe out the most vulnerable corals.

Coral reefs are the world’s most valuable ecosystem ( below, De Groot et al., 2012, Global estimates of the value of ecosystems and their services in monetary units, Ecosystem Services 1:50–61). Since most global economic ecosystem service losses are from coral reef degradation (Costanza et al., Changes in the global value of ecosystem services, 2014, Global Environmental Change, 26:152-158), we can expect severe economic consequences for all tropical coastal countries, especially for island nations.

The last hope to preserve coral reefs and the species and people who depend on them now lies in urgent large-scale:

  1. deployment of Biorock Coral Arks, the only method that protects corals from dying from extreme high temperature bleaching events
  2. atmospheric carbon dioxide removal to reduce CO2 to safe pre-industrial levels (Geotherapy)

The survival of coral reefs and of billions of people who depend on them are at stake.

Biorock™ Coral Ark grows elkhorn in Jamaica

Elkhorn coral, Acropora palmata, was the most common coral in shallow Jamaican and Caribbean reefs in the early 1950s until the corals were killed from sewage pollution, global warming, soil erosion, and new diseases. Now it is locally extinct almost everywhere around Jamaica and the entire Caribbean, with only small surviving populations at isolated spots, and the species is regarded as severely endangered throughout its entire range.

The Biorock™ electric reef restoration method was invented in Jamaica in the 1980s, and immediately found that elkhorn coral, staghorn corals, and all other local species of corals were growing on Biorock reefs at record rates even in locations where they would otherwise have died from poor water quality (T. J. Goreau & W. Hilbertz, Reef restoration using seawater electrolysis in Jamaica, 2012, in T. J. Goreau & R. K. Trench (Editors), Innovative Technologies for Marine Ecosystem Restoration, CRC Press).

Biorock is again being used in Jamaica to grow a small elkhorn reef at a site that was once covered with vast elkhorn forests, and where now only a small handful of surviving small colonies remain. When these are broken naturally by storms, we rescue the small broken fragments, most of which die from rolling around on rocks and algae, transplant them onto the small Biorock reef, and grow them into large colonies.

These photos show the prolific growth of these newly transplanted fragments. After a month or two there are large numbers of white areas which mark very rapid growth of coral polyps forming new branch tips, each of which will elongate into a separate branch. Some of these fragments are forming more than a dozen new branches. GCRA will post photographs of the growth of corals on the Biorock Elkhorn Coral Ark from time to time.

Besides Jamaica, Biorock Coral Arks™ are currently growing elkhorn, staghorn, and many other species of Caribbean coral in Panama, St. Barthelemy, Curaçao, and Grenada, and around half the world’s coral species at around 500 Biorock Arks in Indonesia.

All photos below by Dan Brewer, January 11 2019.


10 years ago on Gaia Discovery – Thomas Goreau on Coral Restoration with Biorock

As published in Gaia Discovery on August 8, 2008

by Mallika Naguran

He is a pained man on a mission. Dr Thomas J Goreau is sickened with seeing widespread and massive destruction of coral reefs that were once resplendent underwater rainforests, a joy to fishes and fishermen alike.

And he has no choice but to act as the value of reefs is immeasurable. “Coral reefs provide most of the marine biodiversity, fisheries, shore protection, and tourism for over 100 countries. All of this depends on having healthy corals. No other organism can do this,” says Tom.

The President of the Global Coral Reef Alliance (GCRA) is charged up to reverse the situation with a bit of help from technology. “To restore reefs we must eliminate the stresses that damage corals and use new methods to grow them faster and more resistant to stress,” he says.  

Technology to Help Grow Corals

Tom has an illustrious career. He was previously Senior Scientific Affairs Officer at the United Nations Centre for Science and Technology for Development, in charge of global climate change and biodiversity issues, and has published around 200 papers in areas such as coral reef ecology, changes in global ocean circulation, tropical deforestation and reforestation and mathematical modeling of climate records.

Tom developed the method to predict the location, timing, and severity of coral bleaching from satellite data with Ray Hayes. In 1990 Tom formed GCRA, a non-profit organization for coral reef protection and sustainable management, with a network of volunteer scientists, divers, environmentalists and organizations.

Corals grow 3 to 5 times faster with Biorock.

Using technology as a means, essentially Biorock that was invented by the late Wolf Hilbertz, they address the needs of coral reef restoration, marine diseases and issues caused by global climate change, environmental stress and pollution.

The method allows reefs to survive and recover from damage caused by excessive nutrients, climate change, and physical destruction. To build a Biorock reef, a low voltage electrical current is passed through a conductive frame that’s anchored to the seabed. Power can be sourced from chargers, windmills, solar panels or tidal current generators.

The electrolytic reaction causes mineral crystals such as calcium carbonate and magnesium hydroxide found in seawater to grow on the structure. Within days, a whitish hue that is made up of precipitated minerals coat the structure’s surface – a sign that the wired frame is ready for action.

Divers then begin transplanting coral fragments from other reefs and attach them to the frame. The coral pieces begin to bond to the accreted mineral substrate immediately and start to grow at a rate up to five times faster than usual. Soon the frame with dotted corals becomes a habitat for a reef ecosystem, attracting colonizing marine life such as fish, crabs, clams, octopus, lobster, and sea urchins.

“In the Maldives during the 1998 warming, fewer than 5% of the natural reef corals survived. But on our GCRA reefs, 80% of corals not only survived, they flourished,” says Tom.  Corals from these reefs are now recolonizing the surrounding natural habitats, I am told. GCRA reefs are growing vibrantly in Thailand, Indonesia, Papua New Guinea, Panama, and Mexico.

Growing Up Among Corals

Tom, growing up in Jamaica was swimming as soon as he could walk. “I have dived longer and in more reefs around the world than any coral scientist,” says Tom, previously Senior Scientific Affairs Officer at the United Nations Centre for Science and Technology for Development.

What Tom did to pass time as a boy.

What Tom did to pass time as a boy.

Tom could very well have coral DNA in his cell structure as his father Thomas F Goreau was the first diving marine scientist, researching on coral ecology in 1948. Grandpa Fritz Goreau was notable too for pioneering underwater photography using self-made underwater cameras and breathing dive apparatus. They took the first high quality photographs of coral reef organisms in the Central Pacific, Bahamas, and the Great Barrier Reef among other locations.

“When I was young we would travel around Jamaica where my father would show his underwater photographs to fishermen and tell them why the reefs were disappearing and in danger.  So it is just something I grew up doing and had the fortune of learning from the person who knew the most about coral reefs,” says Tom.

“I continue only because no one else has this background, experience and knowledge, and somebody has to maintain it,” he adds, in spite of losing parts of his hand to a barracuda attack in 2004, which has since been reconstructed.

“There is almost no place that my grandfather, father, or I knew in the past that is not heartbreakingly damaged, many so badly ruined that there is just no trace at all left of the reefs, not even rubble. Most of those who live in those areas now don’t even realize what they have lost,” he frowns.

Seeing is Believing

In spite of evidence that coral reefs are thriving thanks to Biorock where they were once bleached, dead or crushed, the path chosen to save coastal reefs using this proven technology is full of rocks. 

“As a career choice, it has been suicidal to be in a field where there is no funding – it is impossible to survive. I often wish I had not been obliged by circumstance to have to do this and could have had a job that I would be actually paid for.” Among the difficulties he encounters, Tom speaks about the lack of faith.

A new reef is born where once barren.

“No one believes what we do is possible until they see it themselves. Growing bright coral reefs swarming with fish in a few years in places that were barren deserts is something everybody thinks can’t be done, but has been done in nearly 30 countries with only small donations, mostly from local people who remember how their reef used to be and realize they must grow more corals now,” he explains.

Describing local funding as “a drop in the bucket”, he urges the immediate resources from other sources. “Until governments, big international funding agencies, the private sector, and big international conservation groups realize that if we don’t have policies and funding to restore what we have lost, it will very soon be too late.”

Photos by Tom Goreau and Club Aqua, Bali.

Tom, who is also the Coordinator of the United Nations Commission on Sustainable Development Partnership in New Technologies for Small Island Developing States, can be contacted at

Visit his website at

Recharging Indonesian marine biodiversity

Thomas J. F. Goreau, PhD
President, Global Coral Reef Alliance
Scientific Advisor, Biorock Indonesia

Indonesia has the largest and most biodiverse coral reefs, mangroves, and seagrasses of any country in the world. Sadly, all are under severe pressure. Around 95% of the coral reefs have been badly damaged or degraded from bombing, poisons, soil runoff, sewage and chemical pollution, new diseases, and bleaching caused by global warming. More than half the mangroves have been cut and dredged out for shrimp ponds, around half of which have been abandoned due to shrimp diseases. Their loss is causing severe coastal flooding in adjacent, now unprotected, land, such as Jakarta, North Java, Sumatra, Kalimantan, and across South East Asia. Seagrass beds are dying as they are buried in mud from eroded soils washed away from jungles that are being deforested, logged, and converted to oil palm plantations, and as increased sewage and agricultural fertilizers from land trigger harmful algae blooms that smother seagrass and coral reefs. As Indonesia’s priceless coastal ecosystems vanish, fisheries are collapsing, beaches washing away, and rare endemic species may be lost forever.

Sulawesi lies in the central core area of the highest biodiversity in Indonesia, the “heart of the heart” of global marine species diversity. Those reefs that have not been bombed, poisoned, or bleached have the highest coral cover, biodiversity, and growth in the world. The incredible diversity of this area is due to many unique environmental and historical factors, too many to cover briefly here, but which will be covered in a future book on coral reefs. Since GCRA spends almost all our time regenerating the most damaged reefs where only a last few dying corals survive under severe stress, we fully appreciate the need to save the last and finest coral reefs remaining before they too vanish from global warming and pollution.

There is an urgent need for new methods to regenerate damaged coastal ecosystems to maintain the shore protection, fisheries, tourism, and biodiversity services they provide. In the face of accelerating global warming, global sea level rise, and pollution the old ways of restoring these ecosystems have proven to be expensive failures, when conventional coral fragment farms are catastrophically wiped out by bleaching, diseases, and hurricanes, and mangroves and seagrasses laboriously transplanted are washed away by increasingly strong storm waves before their roots can grow. As these stresses increase, future long term success in regenerating these crucial ecosystems can only come with regenerative methods that greatly increase the settlement, growth, survival, and resistance to extreme environmental stresses from high temperature, mud, pollution, and waves. Biorock is the only method that does all these, not just for corals but for all marine animals and plants. Biorock reefs keep entire ecosystems alive during extreme stresses that would kill them, and regenerate entire ecosystems even in severely polluted areas where there has been no natural recovery. Around 500 Biorock Coral Arks built by Biorock Indonesia teams in Bali, Lombok, Flores, Sulawesi, Java, Sumbawa, and Ambon are growing about half of all the coral species in the world, and dramatically increasing the marine biodiversity around them.

GCRA recently filmed prime coral reefs in North Sulawesi with Take Action Films, who are preparing a documentary on long term change in coral reefs. At many of these magnificent sites the shallow reefs are still completely covered with huge table corals, up to 4 to 5 meters across. Deeper waters are dominated by soft corals and sponges. But despite their magnificence, these reefs are not invulnerable to global warming, new coral diseases, and land-based pollution.

Shallow reefs are dominated by table corals, this site is a relatively “poor” reef, it has some of the lowest coral cover, coral size, and diversity seen in these dives

Drop off walls like this are completely covered in bright soft corals and tunicates

This wall site is dominated by trees of the spectacular green-black coral Tubastrea micrantha, and sponges

Large gorgonians are common

But all is not perfect in this underwater Paradise. In 2016 and 1998 high temperature bleaching events killed more than 95% of the corals in reefs across southern Indonesia, and such events are getting more frequent and more severe because of global warming. The hardiest coral species of all, and the last to die from severe bleaching stress and pollution, were found in 2018 to be dying from new disease outbreaks in areas down-current from large shrimp and fish farms. The work of GCRA’s James Cervino and colleagues strongly suggests that these poorly studied diseases are caused by shellfish pathogenic bacteria and viruses spreading from shrimp and fish farms. Working in research partnership with Institut Pertanian Bogor, Indonesia’s top agricultural and fisheries research university, Biorock Indonesia and the Global Coral Reef Alliance hope to identify the pathogens causing the new coral disease outbreaks and determine how they are linked to commercial mariculture.

In November 2018 Biorock Indonesia trained local teams in Ambon, to save the last corals left in badly polluted Ambon Bay:

Ambon Bay is a model for restoring damaged reefs, mangroves, and seagrasses in severely polluted areas like Jakarta Bay, Surabaya, Makassar, Balikpapan, and all the other coastal cities imperiled by sea level rise all along the shores of South East Asia.

Outbreaks of coral eating snails and starfish are also making severe inroads on prime reefs.

This large soft coral has been eaten in patches by two large cowrie snails with black tissue covering their white shells, above the finger, which points to a mass of brown eggs laid on the soft coral tissue. Another mass of white eggs of a different species were seen nearby on the same coral. Although the snail eats the soft coral, it does not kill it, and previously damaged, now recovering, portions are seen. The damage done by Drupella snails to hard corals is vastly more severe, and is be worse than Crown of Thorns damage in many places

In the Red Sea islands off the coast of Ethiopia and Eritrea in the early 1960s the late Professor Tom Goreau first discovered how Acanthaster starfish eat corals by extruding their stomach out through their mouth, covering and digesting coral tissue, and then pulling their stomach back inside their mouth. He had first collected live specimens of Acanthaster starfish at Bikini Atoll in 1947, when they lived in deep caves and only came out at night. It is not known what predator they were hiding from that controlled their populations at that time. In the late 1960s, when huge swarms were first documented in the Western Pacific, he led studies of major outbreaks in Saipan, Guam, and Palau. Swarms of half a million or more starfish migrated around entire islands eating all the corals, until they starved to death because there were no more corals left to eat. The reefs then recovered over a decade or so, but only if they were in prime quality water free from global warming, pollution, disease, and other human impacts, until a new swarm of starfish grows and eats them. Recovery was rapid in the old days, a decade or so, but now recovery is exceptionally rare because of accelerating human-caused environmental deterioration.

In the finest reef seen, with spectacular coral cover and diversity, we found and removed a small herd of coral eating crown of thorns starfish, Acanthaster planci

Removing the starfish has to be done very carefully because they are covered with toxic spines. In this case the only tools we had were a small bag and a pointer stick

This coral, broken and flipped over by a storm or by anchor damage, is being turned back over to its right side

Also in 2018 an earthquake in Lombok did damage to many Biorock projects in the Gili Islands, mostly to the power supplies destroyed in fallen buildings. The Gili Eco Trust, our local partner, has been busy repairing the damage.

Despite all these threats, Indonesia still has the world’s largest and most diverse coral reefs, mangroves, and sea grasses, but in the future they will be even more threatened than before when global warming, global sea level rise, and pollution, and human pressures get worse.

Biorock Indonesia, GCRA’s partner, is doing its best to train local groups to set up community-managed Biorock Coral Arks across Indonesia to regenerate entire ecosystems. The Global Coral Reef Alliance’s Thomas Sarkisian recently tested new, much more efficient power systems, needing much less maintenance in Bali, and Biorock Indonesia hopes to upgrade the performance of projects across the archipelago as soon as funds can be raised. At the same time Biorock Indonesia & GCRA are working to develop and expand sustainable community-based mariculture technologies for corals, fishes, lobsters, oysters, giant clams, sea grass, mangroves, and many other species. We thank Take Action film for their support in getting to these sites.

Biorock Barong And Rangda reef installed in honor of Agung Prana

Thomas J. F. Goreau, PhD
President, Global Coral Reef Alliance
Scientific Advisor, Biorock Indonesia

The late Agung Prana, a leader of Balinese ecotourism, was commemorated by installation of a Biorock reef shaped like the quintessential Balinese mythological figures, Barong and Rangda, at the Pemuteran Sea Festival on December 14, 2018.

Agung Prana

Agung Prana pioneered Pemuteran development based on traditional Balinese philosophy of balance and harmony between humans and nature. His goal was to preserve natural beauty for a serene tourism experience, and regenerating coral reefs was part of that vision. Pemuteran’s peace was the opposite of the constant hustle and bustle in densely crowded tourist areas in the south of Bali, where rice fields are paved over with concrete, beaches fouled with plastic, and you can’t hear the waves over the noise.

Thanks to Agung Prana’s support, more than a hundred Biorock reefs were built in front of Taman Sari Resort in Pemuteran, each a different size and shape, the largest concentration of reef restoration projects in the world. Pemuteran changed from one of the poorest villages in Bali to one of the most prosperous, because visitors came from all around the world to swim over beautiful corals and spectacular fishes, right in front of the beach. These projects have received many global awards for ecotourism and environmental leadership, including the United Nations Equator Award for Community Based Development, and the Special UN Development Programme Award for Oceans and Community Development.

Oka Dwi Prihatmoko, Putu Catra, Bagus Mantra (holding his father’s portrait), Made Gunaksa, Rani Morrow-Wuigk, Komang Astika, & Kadek Astawan at Agung Prana’s funeral

Agung Prana was a traditional Balinese leader from the old kingdom of Mengwi, with major responsibilities in maintaining ancient Balinese culture. To honour him, the quintessential Balinese Tale of Barong and Rangda was the obvious choice. Barong, the lion who represents Good, confronts Rangda, who represents Evil, in battle to maintain the balance of the universe. The dramatic Barong dance, accompanied by beautiful Gamelan gong orchestra music, tells the most famous Balinese tale, intimately familiar to all Balinese and the core of presentations of Balinese artistic traditions to visitors.

The Barong and Rangda Biorock sculpture was designed and built by Made Gunaksa at the Biorock Centre.

Made Gunaksa building the Barong

The installation team was led by Komang Astika of the Biorock Centre, wearing wearing white shirt at centre. Tom Goreau, scientific advisor to Biorock Indonesia, is at his right, Rangda between them wears a flower wreath, with some of the many volunteer divers.

The complete Barong and Rangda Biorock reef structure was borne into the water by a large and enthusiastic team of divers.

It was floated with air barrels and swum to the site.

Underwater team lowering and moving the reef to the installation site

It was a truly mythological vision underwater.

Corals were attached to the reefs.

Corals starting to grow on the new reef.

The day after installation and the structure being electrified the rust had vanished from the sheet steel on the Barong and Rangda figures the rebar base had begun to turn white with new limestone growth, and new coral growth could be seen where corals had begun to attach themselves to the structure.

The project uses an innovative new power supply designed by Thomas Sarkisian of the Global Coral Reef Alliance. Measurements the next day after installation showed it was delivering as much direct current trickle charge to the structures as the old power supplies, but using only around one third the alternating current from land. Not only will the more efficient power supplies use much less power, they will also require much less maintenance.

Installation of the Agung Prana Memorial Barong and Rangda Biorock Reef was filmed by Take Action Films from Toronto for their forthcoming film on long term change in coral reefs.

The Global Coral Reef Alliance and Biorock Indonesia thanks the family of Agung Prana, the Biorock Centre staff, Taman Sari Resort, the village and people of Pemuteran, and all the many people, far too many to mention in a report this size, who helped as volunteers and sponsors for helping this unique project to happen. We will periodically post photographs and video of the project.

Biorock beach regeneration expands

Thomas J. F. Goreau, PhD
President, Global Coral Reef Alliance
Scientific Advisor, Biorock Indonesia

The severely eroded beach at Pulau Gangga Resort, North Sulawesi, Indonesia that was naturally regenerated at record rates with Biorock Anti Wave (BAW) reefs (Goreau & Prong, 2017) continued to grow throughout 2018, even through the monsoon season when they normally would have eroded. A second set of BAW reefs on another side of the island grew back an additional severely eroded beach within months of installation, during the monsoon erosion season on that side of the island. Coral, barnacle, oyster, sea urchin, crab, fish populations, and seagrass and sand-producing calcareous algae continue to increase around the BAW reefs.

When the project began in early 2016 there was a 1.5 meter high erosion cliff in the sand right at the front edge of the beach huts, which were about to be moved inland before they could fall into the sea. The tree at center had collapsed on its side into the sea. The fallen horizontal trunk is now buried underneath the sand and a former side branch is now forming a new vertical trunk. Most of the beach growth took place in the first three months as the beach profile turned from concave to convex, but the beach has continued to grow continuously since, throughout both calm and rough monsoon seasons. On this beach erosion is caused by winds from the northwest (at left) during the Australian Monsoon.

From above. By late 2018 the high tide mark had moved seaward by about 10 meters, and the low tide mark by about 15 to 20 meters, as the beach steadily grows.

Looking south beyond the end of the project, the naturally widened beach has extended to the southern end of the island. Strong longshore currents carry sand from bottom to top along the beach. At low tide the tops of a new set of BAW reefs installed by Paulus Prong in mid 2018 can be seen at top left. The unprotected beach on that side had continued to erode after the first beach grew back, so Paulus Prong installed a new set of BAW reefs in front of the eroding beach in mid 2018. That beach had eroded at the opposite season from winds from the southeast during the South East Asian Monsoon.

In mid 2018 the tree at top left was about to fall down because the sand underneath it had completely washed away, the trunk was hanging in the air supported by horizontal roots from the land side, and an erosion cliff about 1 meter high ran along the top left of the image. Beach growth in less than six months is now burying the BAW structures that were closest to the shore.

Beach regeneration at record rates appears due to the fact that wave energy is dissipated by diffraction and refraction through BAW reefs, with little erosion-causing wave reflection, always caused by solid sea walls, and to growth of new sand around structures by calcareous algae. Rates of beach growth naturally depends on wave energy, tidal range, and longshore currents, so will be different at every site.

These extraordinary results suggest that BAW reefs could also turn severely eroding beaches into growing ones at many other places, especially low-lying islands like Pulau Gangga that are already suffering from flooding,caused by global sea level rise and death of coral reefs by global warming.

Read also and watch

Coral Bleaching: Global Warming versus Ocean Acidification

T. J. F. Goreau & S. Muka, Letters, American Scientist, 2019, 107:4


To the Editors:

Sam Muka’s article “Trashing the Tanks” propagates the most perniciously widespread and hard-to-eradicate falsehood about corals: that bleaching and mortality are due to acidification rather than a high temperature. Every article about ocean acidification shows photos of corals that were bleached by an excessively high temperature, despite the fact that acidification does not cause bleaching at all!

Most of the corals in the world have now already died from heat shock caused by excessively high temperatures resulting from global warming, as Ray Hayes, Peter Glynn, Ernest Williams, and I predicted would happen almost 30 years ago after the planet suddenly passed the high-temperature tipping point for global-scale mass coral bleaching in the 1980s. Acidification only dissolves skeletons of corals long
after they have died from heat shock.

Reducing carbon dioxide (C02) in time to prevent global warming— caused extinction of coral reef ecosystems automatically prevents later damage from acidification, but controlling C02 in time to prevent acidification guarantees that global warming will kill them by heat stroke. Focusing C02-control efforts to prevent ocean acidification instead of global warming is a scientifically irresponsible and politically dangerous red herring.

Thomas J. F. Goreau
President, Global Coral Reef Alliance
Cambridge, MA

Dr. Muka responds:

Thank you for the clarification. You are correct that coral bleaching is caused by the evacuation or death of photosynthetic organisms from coral structures. If those photosynthetic organisms don’t return, the polyps die and all that is left is a “bleached” shell. Ocean acidification does not cause bleaching, but instead causes the dissolution of the calcium structure that makes up the coral. Ocean acidification occurs in warming seas, but it is not the primary killer of corals, nor will it ever be. The ocean would already have to be too warm for the survival of coral polyps before it was acidic enough to result in direct coral death.

However, I’m unsure that the differentiation affects the way the public understands their role in climate change, broadly speaking. The steps that aquarium visitors would be told to take (contact representatives, reduce fossil fuel use, lower their carbon footprint) are the same because, hopefully, anything they are taught to do would decrease warming and, by default, acidification.

Happy Winter Solstice! 2018 GCRA activities report


by Thomas J. F. Goreau, PhD, President, Global Coral Reef Alliance

BARONG & RANGDA, Biorock sculpture of the quintessential Balinese myth of the struggle between good and evil, installed December 14 2018 in honor of late Balinese ecotourism pioneer Agung Prana.


Indonesia, the country with the world’s largest areas and highest biodiversity of coral reefs, mangroves, and sea grass ecosystems, continued to be the major focus of GCRA activities in 2018, in collaboration with our local partner, Biorock Indonesia.


Sulawesi is the centre of global marine species diversity, the “heart of the heart” of the richest variety of species in the world’s oceans. The GCRA team, working with Take Action Films, a Toronto documentary group, filmed spectacular coral reefs in North Sulawesi. We found, and removed, Crown of Thorns starfish (Acanthaster planci) eating corals in the finest reefs. Although these reefs have the highest live coral cover and diversity in the world, they are not invulnerable to stresses caused by humans, in particular global warming and new diseases. 10 Biorock reefs at Pulau Gangga Dive Resort, which had been off power for around 8 years, were put back under power and immediately began growing again, with spectacular corals and fishes. The severely eroded beach at southwestern Pulau Gangga, which Biorock shore protection reefs grew back naturally at record rates (at a fraction of the cost of a seawall that would have increased erosion in front of it), continued to grow wider, higher, and longer throughout 2018, throughout the monsoon season when it would previously erode.  Corals are settling on the Biorock structures and growing very rapidly, as are the surrounding seagrasses, while fishes, sea urchins, barnacles, oysters, and crabs have built up dense populations. A second severely eroded beach on another side of the same island was grown back in months during the erosion season with Biorock shore protection reefs built by Paulus Prong and a local team trained by GCRA. These projects were shown to the Mayor of the local fishing village, which is suffering severe beach erosion and flooding of land because of death of their shallow coral reefs, and community-managed Biorock shore protection, reef restoration, and sustainable mariculture projects were discussed.


Over a hundred Biorock reefs, each a different size and shape, continue to grow and provide fish habitat, creating an ecotourism attraction that has turned Pemuteran village from the poorest on the island to one of the most prosperous. The Biorock projects have received many international environmental awards, including the United Nations Equator Award for Community Based Development and the Special UNDP Award for Oceans and Coastal Management. Biorock reefs increased live coral cover from around 1-5% after the severe bleaching event of 1998, up to 95-99% in less than ten years, with spectacular coral settlement and growth, increasing the biodiversity of corals and fishes above what it had originally been before the bleaching event. Another severe bleaching event in 2016, coincident with severe damage from heavy waves, and severe infestations of coral-eating Crown of Thorns starfish and Drupella snails, decreased the live coral cover of nearby reefs below 5%. The Biorock projects showed an interesting pattern. Biorock reefs under continuous electrical trickle charge had almost no coral mortality during the bleaching event, while those under power only 6-8 hours a day suffered almost complete coral mortality, like surrounding reefs. Similar results were seen at around a hundred Biorock projects at Gili Trawangan run by our local partner, the Gili Eco Trust, headed by Delphine Robbe. Community-based Biorock projects in Pejarakan, Bali had almost complete survival through the severe bleaching event that caused nearly complete mortality on nearby reefs. These results reiterate what was found in the Maldives in 1998, and Thailand in 2010, that Biorock is the only method that saves entire reefs from dying from bleaching, if they are under continuous power. Biorock Coral Arks are helping save around half the world’s coral species from extinction from global warming. The Biorock Centre team in Pemuteran, led by Komang Astika, has been vigorously propagating corals, and there has been high natural settlement of new corals in the Biorock electrical fields, which is not seen further away. Young corals are growing vigorously and the Biorock team is growing back reef coral cover and diversity once again. The Pemuteran Sea Festival in mid-December drew crowds of thousands of people, and more than 50 divers joined in to install a stunning new Biorock reef, in the form of Barong and Rangda, the two characters of the quintessential Balinese myth. This new structure was dedicated to the memory of the late Agung Prana, owner of Taman Sari Resort in Pemuteran, a leader of Balinese ecotourism based on restoring beautiful gardens on both land and in the sea. Without him these projects would not have happened. Within a day most of the rust on the new steel structure had disappeared, limestone began growing on it, and new coral growth was visible.

Kalimantan (Borneo)

Last year Indonesia was for a few brief weeks the world’s largest CO2 emitter when drought conditions led to massive fires in peat soil that had been clear cut for oil palm plantations. GCRA and Biorock Indonesia assessed illegally cut mangroves in East Kalimantan (Borneo), with Willie Smits and the Arsari Enviro Industri team. We will work with them to use Biorock Technology to greatly increase rates of above and below ground growth of mangroves, ameliorate soil acidity, reverse peat oxidation, create huge carbon sinks, provide orangutan sanctuaries, and produce biofuels from the endemic swamp palm Nypa fruticans, which produces as much energy from sustainable tapping of flower stalks as sugar cane does, and without cutting down the plant. These projects are planned to start next year, as well as projects to grow corals 20 kilometers up-river, which enormous tides make salty enough for coral growth. These projects may allow Indonesia, which has the world’s largest and most diverse mangroves and sea grasses, to restore mangrove and sea grass peat soils and hopefully become the world’s largest and most cost-effective carbon sink.


The Biorock Ambon team held training workshops, installed new Biorock structures with local participants, and maintained the older projects in Halong, Ambon Bay. Ambon Bay was once famous for its clear waters and spectacular coral gardens. Corals were among the thousands of Ambon plants and animals described by the great blind naturalist Rumphius in the 1600s, and in the 1800s Alfred Russel Wallace, co-discoverer of Evolution, was astonished to look over the side of a boat at coral reefs that were just as magnificent and beautiful ecosystems as the Indonesian forests he studied, but he could not go into the water to see them. Since then, deforestation, agriculture, urbanization, sewage, garbage, and plastics have killed almost all the coral reefs in Ambon Bay, with the last remaining remnant in Halong. Biorock projects are now bringing them back.


The Biorock Indonesia team, led by Prawita Tasya Karissa and Ricky Soerapoetra, met with the Ministry of Marine Affairs and Fisheries and the United Nations Development Program to plan future large-scale reef and fisheries restoration projects all across Indonesia. A collaborative research program was formally signed with the Institut Pertanian Bogor (Bogor Agricultural University), which will be led by two of Indonesia’s leading young coral researchers, Hawis Maduppa and Beginer Subhan, who both did their Master’s thesis on Biorock projects.


100 Biorock projects at Gili Trawangan were affected by the severe earthquake that hit Lombok. There was no electricity for months, and many power supplies were lost under collapsing buildings. While there was little damage to the Biorock reefs themselves, nearby reef blocks broke loose and slid downslope. Delphine Robbe of the Gili Eco Trust, the local GCRA partner, has led heroic efforts under difficult circumstances to repair the damage and get the Biorock projects back under power.





Six new Biorock coral reefs were built and installed in Cozumel, the world’s most popular dive site, in collaboration with the Cozumel Coral Reef Restoration Foundation, funded by Minecraft. These are illuminated at night with LED lights, attracting zooplankton, fishes, and squids.

Costa Maya

Sites along the Costa Maya, the east coast of Yucatan, from Cancun to Mahahual, were assessed for water quality problems, resulting from tourism over-development and failure to treat sewage, which are causing rapid death of the corals by smothering from harmful algae blooms and coral diseases.  Algae were collected for nutrient analysis to identify the sources of pollution causing their proliferation. This work was done with Mexican diving organizations, including Sea Shepherds Mexico, and Mexican algae experts, including Pamela Herrera.


Plans moved forward to develop some of the world’s largest tidal energy resources, in the Sea of Cortes territories of the Comca’ac people, Mexico’s smallest and most remarkable indigenous culture. Expected to start next year they will produce electricity, water from desalination, and Biorock building materials, and develop sustainable mariculture of endemic endangered marine species.



Meetings were held with Guna Indian representatives to plan Biorock coral reef shore protection projects to protect their islands from severe erosion. A quarter of the 50 inhabited islands are now being abandoned because they can no longer be protected from global sea level rise, making their people climate change refugees. Biorock will also be used to restore coral reef fisheries habitat, especially for the lobsters on which the Guna economy depends, and to develop sustainable ecotourism.  GCRA’s study of coral reefs in front of the Panama Canal was used by the Panamanian environmental law group Centro de Incidencia Ambiental to get a Panamanian Supreme Court order issued to halt the dredging for landfill 100 meters away that threatened these reefs. The developers have ignored the legal orders.


GCRA, the Grenada Coral Reef Foundation, and the Grenada Fisheries Department Marine Protected Area Programme held Biorock training workshops for local students and fishermen, in Gouyave, Grenada’s largest fishing village, and in Carriacou, the largest island of the Grenadines. At each site eight Biorock reefs were built and installed by workshop participants. It is planned to greatly expand these projects in the coming year.



GCRA assessed severe coastal erosion sites in Maui where beaches have washed away, cliffs are collapsing, and condominiums, houses, and roads are on the verge of collapsing into the sea. Traditional sea wall and breakwater strategies have proven repeatedly to be costly failures. GCRA is proposing use of Biorock shore protection reefs with local partners, and met with local regulatory agencies to evaluate the barriers to getting permission to use much lower cost and much more effective Biorock strategies to grow back beaches and restore coral reefs.



At the Amsterdam International Summit on Fisheries and Mariculture Tom Goreau gave an invited keynote talk on “Biorock Technology: A Novel Tool for Large-Scale Whole-Ecosystem Sustainable Mariculture Using Direct Biophysical Stimulation of Marine Organisms’ Biochemical Energy Metabolism”.



GCRA repaired storm damage to cables at the Biorock Elkhorn reef in Westmoreland, Jamaica, strengthening the structure and adding more corals. This is the first Biorock coral restoration project in 25 years in Jamaica, where the technology was originally invented and developed. Proposals were prepared with the Caribbean Maritime University, Portland Bight Marine Protected Area, Caribbean Coastal Areas Management Foundation, and the Half Moon Bay Fishermens’ Cooperative to use Biorock shore protection reefs to grow back Jamaica’s most important recreational beach at Hellshire, St. Catherine, which has entirely washed away, and to restore the dead reef that used to protect it.



At the SIDS DOCK Side Event “Blue Guardians: Building Partnerships for the SIDS Blue Economy” in Apia, at the United Nations Inter-Regional Meeting for Small Island Developing States Tom Goreau gave an invited keynote talk on “Recharging SIDS coral reefs, fisheries, sea grass, mangroves, beaches, low coasts and islands, and producing CO2-removing construction material”. He met with the Secretariat for the Pacific Regional Environment Programme, looked at community-managed Giant Clam farms that could greatly benefit from Biorock Technology, and had meetings to develop sustainable mariculture, reef restoration, and shore protection projects in Tonga, Samoa, Vanuatu, Fiji, Niue, Tokelau, Tuvalu, and the Cook Islands.



At the Global Eco Asia Pacific Tourism Conference in Townsville Tom Goreau gave an invited keynote talk on “Ecotourism Can Help Save Indonesia’s Coral Reefs”, showing how devastated reefs, beaches, and fisheries have been restored by Biorock Indonesia in front of Indonesian hotels. He pointed out for every reef we save, thousands are being lost, but if every hotel were legally mandated to restore the dead reefs in front of their eroding beaches, tourism could be part of the solution instead of part of the problem. GCRA worked with Dr. Peter Bell of the University of Queensland (who discovered that land-based sources of nutrients from agricultural fertilizers, cattle farms, and sewage had killed around three quarters of the Great Barrier Reef’s corals even before coral bleaching killed most of the rest, as Tom Goreau had accurately predicted 20 years ago) to re-evaluate the changes to the coral reefs at Low Isle. Low Isle is unique in the history of coral reefs, because it was intensively studied in 1928-1929 by the Cambridge University Great Barrier Reef Expedition, led by Sir Maurice Yonge, who adopted the Goreau family as his scientific heirs. Low Isle, and many other reefs in the Great Barrier Reef, were first photographed underwater, and from the air, in 1950, by Fritz Goreau. They were photographed again in 1967 by his son Thomas F. Goreau, and again in 1998 by his son Thomas J. F. Goreau. These photographic records, unknown in Australia, show dramatic long-term changes in the coral reefs before any Australian coral reef scientists began to study them. The GCRA team also looked at coastal fringing coral reefs with local Kuku Yalanji Aboriginal communities, who had seen their reefs and sea grasses killed by mud and nutrients washed in from sugar cane farms, and with local organic farmer Andre Leu who has increased his soil carbon six-fold, greatly increasing soil water storage during recent record high temperatures and droughts, and greatly reducing soil erosion and nutrient loss onto the coral reefs. Meetings were held with Great Barrier Reef Heritage and local groups trying to protect the Great Barrier Reef’s last corals, to develop educational exhibits of changes in reef conditions over the last 90 years and to restore them.



GCRA’s Margaret Goreau has begun to scan the Goreau collection of coral reef photographs from the 1940s, 1950s, and 1960s, the world’s largest. They show a lost world that had largely vanished before any other diving scientists saw it. These will form part of full-length documentary film that shows the changes in reefs around the world since they were first documented, the causes of their deterioration, and how deterioration can be reversed. Take Action Films, a Toronto-based documentary film group directed by Andrew Nisker, was funded by the Canadian Government to film the long-term changes shown by this unique photograph collection. Take Action films recently released a documentary, Ground Wars, on the environmental and health impacts of golf course chemicals, featuring Tom Goreau and James Cervino of GCRA showing the impacts of golf course fertilizers and chemicals killing corals on Bahamas reefs by causing overgrowth by harmful algae blooms and coral disease epidemics.



Tom Goreau met with the Ahiarmiut Inuit community in Arviat, Nunavut, in the Canadian Arctic. They were the only inland Inuit people, known as the “Caribou Eskimo” or the “People of the Deer”. He brought photographs taken in 1954 by his grandfather, of the last year that the Ahiarmiut people lived on their ancestral tundra lands, just before they were starved out by the collapse of the caribou populations caused by over-hunting. Three of the oldest people in the community, shown in the photographs as young people or children, were still alive, remembered his grandfather well, and could identify all the people in the photographs. Plans were developed to seek funds to scan the entire photograph collection to be made available to the community, who were overjoyed to see them. Discussions were also held about their experiences of climate change, in one of the fastest warming parts of the world. The seasons have dramatically changed because of global warming, new plants, animals, birds, and insects are invading the tundra from the south. Despite global warming, this is one of the few places NOT experiencing global sea level rise. The land is rising rapidly, bouncing back up from the melting of 3 kilometers of ice at the end of the last Ice Age, so islands that were only reachable by boat are now part of the mainland, the rivers that they used to kayak up to hunt caribou are now too shallow, vast numbers of ponds are now drying up, the organic peat on their bottoms are oxidizing and feeding CO2 into the atmosphere, the period of snow cover is decreasing and the vegetation becoming taller, so the land absorbs much more heat. Their entire way of life is threatened by global warming.



The Biorock oyster and salt marsh restoration projects by James Cervino, Rand Weeks, and Tom Goreau successfully restored these ecosystems at the Superfund toxic waste dump at College Point, Queens, New York City and built up a new beach over 11 years that was not damaged by Hurricane Sandy, which caused tremendous erosion elsewhere. In 2018, the New York City Department of Environmental Protection, which had permitted the oyster and salt marsh restoration project, built a huge storm drain that flushed contaminated runoff straight onto the beach we had built up over 11 years, and washed it away with huge erosional gully in just a few months. We are trying to get them to mitigate the damages.



The Talanoa Dialog is a new mechanism to submit important new sources of independent information to the UNFCCC Negotiators. GCRA’s Tom Goreau, Ray Hayes, and Ernest Williams submitted a GCRA White Paper entitled: We Have Already Exceeded the Upper Temperature Limit for Coral Reef Ecosystems, Which are Dying at Today’s CO2 Levels.  Kevin Lister, Sev Clarke, Michael MacCracken, Alan Gadian, Tom Goreau, and Ray Hayes submitted  The essential role and form of integrated climate restoration strategy; the setting of targets and timescales; the methodologies and funding options. We can only hope that the world’s governments act immediately to reverse global warming by putting the dangerous excess CO2 back into the soil in time to prevent the extinction of coral reefs, and many other ecosystems. Political irresponsibility, willful ignorance, and greed are causing accelerated global warming and sea level rise, which will result in catastrophic melting of the polar ice caps, eventually causing 50 meters or more of global sea level rise, forcing billions of people from their homes, which will take millions of years for nature to undo. Politicians lying about global climate change to keep a few campaign donors filthy rich from fossil fuels are committing capital crimes against the environment.



Tom Goreau spoke at the Boston opening of “Symbiotic Earth”, a film about the late scientific genius Lynn Margulis, about his family’s personal ties to her since the 1940s. Tom Goreau interviewed famous linguistic theorist, social critic, and philosopher Noam Chomsky on the origins of the movement for social responsibility of scientists and engineers, based on the 1969-1970 MIT student strike against weapons research on campus. This was filmed by Werner Grundl and Julie O’Neill of Videosphere, a Cambridge documentary group, and is planned to be part of a documentary and book.

Mangrove restoration in Borneo for carbon sequestration, sustainable biofuels, and orangutan sanctuary

Biomass Energy with Carbon Capture and Sequestration (BECCS) and many fake “sustainable biofuel” projects continue to misinform about their net impacts using false carbon accounting.

Some examples are given in this New York Times article, which unfortunately fails to discuss solutions:

Last year, when the deforested peatlands cleared for oil palm burned in forest fires, Indonesia was briefly the world’s largest CO2 emitter, even more than China or the US!

Indonesia has the world’s largest mangroves, and around half of them have been destroyed.

Most have been destroyed with international “development” funds, in order to create shrimp ponds, around half of which have been abandoned due to disease.

Indonesia now protects mangroves, but the north coast of Java, which used to be mangroves, are now water, causing flooding inland due to sea level rise. 

If they were regenerated, Indonesia could be the world’s largest and most cost-effective carbon sink.

The Biorock method, originally developed for coral reef and coastal fisheries regeneration, greatly increases marine plant above and below ground production, and increases carbon storage in sediments. 

Willie Smits of Arsari Enviro Industri (a pioneering Indonesian environmental restoration group restoring vast areas of Borneo devastated by logging and unsustainable oil palm plantations), Biorock Indonesia, the Mangrove Action Project, and Indonesian mangrove researchers are trying to find funding to use Biorock restoration methods to restore Borneo mangroves that were illegally clearcut for palm oil plantations, whose peat carbon is now oxidizing and turning into CO2 as the result of deforestation and drainage.

Our goal is to turn this devastated area into an orangutan sanctuary, a carbon sink, and a producer of truly sustainable biofuels.

These will be produced from sustainable tapping of the flower stalks of Nypa fruticans palm, endemic to these swamps, which unlike sugar cane, does not need to be cut down or fertilized to produce biofuels. 
The area where the project will take place:
Orangutan and Nypa palm:

Updates on Biorock Ambon project

Today the Biorock Indonesia team, led by Komang Astika and Sandhi Raditya, placed the three new Biorock reefs installed yesterday under power in the Inner Ambon Bay.

All are now working, along with the 5 Biorock reefs previously installed, a church, a mosque and the three part symbol of Pertamina, the sponsor of the project.

The new structures are shaped like the spices Ambon was famous for exporting in colonial days, the nutmeg and the clove, and the traditional symbol of Ambon, the Halaloe or Nunusaku.
Simplified Nunusaku
We would like to thank the hard working Biorock Ambon team:

Ruselan Sudharna, Gerald Istia, Christian Pattipeilohy, Zakarias Pakaila, Johannis Manuhutu, and the many volunteers, including the entire welding and boat transport team from Balai Pelatihan dan Penyuluhan Perikanan (the Ambon office of the Maluku Fisheries Department of the Indonesian Ministry of Fisheries and Marine Affairs), Stefani Teria Salhuteru, Meltris Wenno, and Abdul Maskur Marasabessy of Moluccas Coastal Care, students from Universitas Pattimura, Oktovianus Kareis and Raflnicols of Mafispala, local environmental organizations Green Moluccas, and Trash Hero Ambon. We thank Stella Tupenalay, Ibu Raja of Negeri Halong for permission to install the project, and PT Pertamina for funding.

Ambon Bay was once famous for its beautiful corals, but the coral reefs have almost totally collapsed, and the Halong site now has the last corals left in Ambon Bay according to detailed surveys done by local NGO Moluccas Coastal Care. 
Read more about the Biorock Ambon Project 

We would like to thank the hard working Biorock Ambon team:
Ruselan Sudharna, Gerald Istia, Christian Pattipeilohy, Zakarias Pakaila, Johannis Manuhutu, and the many volunteers, including the entire welding and boat transport team from Balai Pelatihan dan Penyuluhan Perikanan (the Ambon office of the Maluku Fisheries Department of the Indonesian Ministry of Fisheries and Marine Affairs), Stefani Teria Salhuteru, Meltris Wenno, and Abdul Maskur Marasabessy of Moluccas Coastal Care, students from Universitas Pattimura, Oktovianus Kareis and Raflnicols of Mafispala, local environmental organizations Green Moluccas, and Trash Hero Ambon. We thank Stella Tupenalay, Ibu Raja of Negeri Halong for permission to install the project, and PT Pertamina for funding.

Ambon Bay was once famous for its beautiful corals, but the coral reefs have almost totally collapsed, and the Halong site now has the last corals left in Ambon Bay according to detailed surveys done by local NGO Moluccas Coastal Care.   

Read more about the Biorock Ambon Project