Tag Archives: coral reef

Corals are putting up a fight against climate change

Climate change is rapidly intensifying pressure on biodiversity around the globe and, particularly, on coral reefs. But despite dramatic losses at the hand of bleaching events, the future of reefs may not be as bleak as we imagined. In two new studies, researchers have discovered that corals may be able to cope with climate change better than we thought, even passing resilience to their offspring. 

Image credit: Woods Hole.

Corals are one of the most vibrant ecosystems on the planet, with many marine species relying on them at some point in their life cycle. Fishes and other organisms find food and shelter and reproduce near them. Despite their relevance, corals are under a lot of stress due to the climate crisis and the expanding marine heatwaves. 

Iconic coral reefs such as the Northwestern Hawaiian Islands in the United States and the Great Barrier Reef in Australia have seen in recent years their worst bleaching on record. And this could just be the start. Further global warming would mean even worse consequences for corals around the world, as highlighted recently by reports.

However, amid massive declines, there are signals that some coral populations have the ability to survive the effects of the climate crisis. A study found that the impact of marine heatwaves on coral communities near the Phoenix Islands Protected Areas (PIPA) in the Pacific Ocean lessened over time, offering hope for some corals. 

The researchers from Woods Hole Oceanographic Institution monitored coral communities at four islands within PIPA, a protected area of 400,000-square-kilometers. They used daily satellite data and temperature loggers to examine how a set of heatwaves in 2002-2003, 2009-2010, and 2015-2016 affected the corals there.

While severely affected by the 2002-2003 heatwave, the corals bounced back and experienced minimal losses in the 2009-2010 heatwave, the study showed. Then, another heatwave in 2015-2016 put twice as much heat stress on the corals, but the die-off was much less severe than expected, which shows a great deal of resilience. 

“It’s easy to lose faith in coral reefs,” first author Michael Fox, study author and coral reef ecologist at the Woods Hole Oceanographic Institution, said in a statement. “But in PIPA, which is protected from local stressors, and where reefs have enough time to recover between heatwaves, the coral populations are doing better than expected.”

While remarkable, the scientists aren’t really sure how the corals are able to pull this off, so their next step will be to better understand this process. They hypothesize that heat-tolerant individuals are repopulation the reefs after a heatwave, which would explain the findings. Still, they caution that corals have limits that could be crossed if the climate crisis worsens.

It’s all about the parents

In another new study, researchers at the ARC Centre of Excellence for Coral Reef Studies at James Cook University suggested that the capacity of corals to adapt to climate change largely depends on traits inherited from their parents. And the ability to pass those adaptive traits is still much present despite the increasing temperatures.

“In particular, corals that are better than average at survival, growth and resisting bleaching stress under future ocean conditions should be good at passing those advantages on to their offspring,” lead author Kevin Bairos-Novak said in a statement. “Still, the current rates of change are too fasts for coral adaptation to keep up.”

The researchers warned that this capacity of adaptation won’t be sufficient if the growing pace of greenhouse gas emissions continues. If climate change happens too fast, there’s just not enough time for evolution to generate new types of corals that can deal with the new weather conditions. That’s all the more reasons to act now on the climate crisis.

The two studies were published in the journals Geophysical Research Letters and Global Change Biology

Scientists discover a deep-sea coral garden off Greenland’s coast

Using an innovative camera, researchers have discovered a deep-sea soft coral garden in Greenland, the first of its kind to have been identified and assessed in Greenlandic waters. This could have implications for the management of deep-sea trawl fisheries that are close to the habitat.

The soft coral garden is located at 1,600 feet below sea level (almost 500 meters), where the pressure is 50 times greater than at the surface. The habitat, delicate and diverse, is full of life with abundant cauliflower corals, feather stars, sponges, anemones, brittle stars, hydrozoans, bryozoans, and other organisms.

The researchers found it using a low-tech rig called a “benthic sled,” which consists of a GoPro camera, lights, and laser pointers, which they set into special pressure-proof cases, mounted on a steel frame and hung from their research vessel. They recorded video at 18 locations and discovered the garden.

“The deep sea is often over-looked in terms of exploration. In fact we have better maps of the surface of Mars, than we do of the deep sea,” said Stephen Long, first author of the study. “The development of a low-cost tool that can withstand deep-sea environments opens up new possibilities for our understanding and management of marine ecosystems.”

The seafloor is a very dark place and that’s why the team needed lights on the rig. The algae that is usually found in corals in shallow waters, giving them their bright colors, can’t survive in the deep sea. But corals can, as well as other organisms that depend on them for shelter. The researchers found over 44,000 individual organisms there.

Surveying the deep sea has so far proved difficult and expensive. This is partly explained by the ocean pressure, which increases by one atmosphere (which is the average atmospheric pressure at sea level) every 10 meters of descent. That’s why surveys in the deep-sea rely on expensive remote operating vehicles and manned submersibles that can tolerate the pressure.

“Given that the ocean is the biggest habitat on earth and the one about which we know the least, we think it is critically important to develop cheap, accessible research tools. These tools can then be used to explore, describe and crucially inform management of these deep-sea resources,” Chris Yesson, co-author, said in a statement.

The discovery is particularly significant as the deep sea is the most poorly known habitat on Earth, despite it covering 65% of the planet. Until very recently, very little was known about Greenland’s deep-sea habitats, their nature, distribution, and how they are impacted by human activities.

Although it’s not that well understood, the deep-sea is crucial to the economy of Greenland. Up to 90% of the exports of the country are owed to fisheries, which is also a crucial source of jobs and food in the country. But the recently found garden and many others could be at risk in the future due to deep-sea mining and bottom trawling.

That’s why the authors call for the garden they discovered to be protected as a Vulnerable Marine Ecosystem under United Nations guidelines. They are also working with the Greenland government and the local fishing industry, who have been receptive to putting protections for the garden in place.

The study was published in the journal Frontiers in Marine Science.

Glowing coral reef despite bleaching offers hope for recovery

Among the victims of climate change, coral reefs are clearly some of the most visible. The rise in seawater temperatures in the world’s oceans has caused the death of many corals in recent years in diverse places from Panama to Seychelles.

Credit Wikipedia Commons

Warmer waters can cause bleaching in corals, turning the coral’s tissue in a ghostly white color and eventually killing it. But, in some cases, something different can happen, with corals turning a bright array of colors as part of their last effort to survive.

That phenomenon is called colorful bleaching and has been observed since 2010 but without much knowledge about it. Researchers have now taken a closer look, discovering that glowing corals are telling us they are trying to survive.

When healthy, corals rely on a mutually beneficial coexistence with tiny algae. Corals get energy from photosynthesis provided by the algae, while the algae take shelter and nutrients from the corals. The pigments from the photosynthesis given by the algae are the reason why many corals appear to be brown.

But this deal can be easily altered by rising ocean temperatures. The algae disappear and the white skeletons of the corals get exposed, looking like they were bleached. The corals usually starve without the algae and finally die. This leads to the collapse of the reefs and their decline, affecting ocean biodiversity.

A colorful last stand

A group of researchers decided to investigate the occurrence and reasons behind the colorful bleaching phenomenon registered in recent years. To do so, they did experiments at the University of Southampton’s Coral Reef Laboratory, exposing common corals to different types of light and conditions.

The experiments showed that the bright colors act as a protective layer, similar to sunscreen, when the algae are no longer attached to the corals, encouraging their return. For Jörg Wiedenmann, lead study author, the colorful bleaching is a way for corals to self-regulate, entering into a feedback loop with the algae.

The algae absorb the sunlight that the corals receive, creating the already mentioned pigments. But when the algae are gone the coral has to deal with that excess sunlight and their white skeletons can reflect it. This causes more stress, preventing the reunion between the coral and algae.

“However, if the coral cells can still carry out at least some of their normal functions, despite the environmental stress that caused bleaching, the increased internal light levels will boost the production of colorful, photoprotective pigments,” Wiedenmann said in a statement.

Wiedenmann and his team recreated in their experiments the ocean temperatures in which the colorful bleaching events happen. They discovered that the phenomenon might surface in less extreme ocean-warning events that are shorter and milder or linked to a reaction to changes in nutrients of the corals.

While this gives hope that the corals can actually recover, the researchers emphasized that improving the quality of the water in the different regions of the world and reducing greenhouse gas emissions represent the best ways to guarantee the survival and continued presence of coral reefs.

“Bleaching is not always a death sentence for corals, the coral animal can still be alive,” said Cecilia D’Angelo, study coauthor. “If the stress event is mild enough, corals can re-establish the symbiosis with their algal partner.”

The study was published in the journal Current Biology.

Help NASA save the ocean’s corals by playing a new video game

The new game will help NASA find new ways of mapping coral reefs. (Image: NASA)

In an effort to save our coral reefs, and thus helping to save the planet, NASA is calling on video gamers and citizen scientists to assist them in mapping coral reefs around the world.

In the past few years, the Ames Research Center in California’s Silicon Valley has been developing new ways to peer below an ocean’s surface using “fluid-lensing” cameras. Mounted on drones or aircraft, the cameras have assisted the agency on expeditions to Puerto Rico, Guam, American Samoa, and elsewhere to collect 3D images of the ocean floor, including corals, algae, and seagrass. However, the data alone is not enough to help them gather the whole story of what is happening to corals, so they are reaching out to the public for help.

The data from the public’s help will be processed by a neural network called NeMO-Net, or the Neural Multi-Modal Observation and Training Network. The program allows players to identify and classify corals using these 3D images while virtually traveling the ocean on their own research vessel, the Nautilus.

On each “dive,” players interact with real NASA data, learning about the different kinds of corals that lie on the shallow ocean floor while highlighting where they appear in the imagery. Aboard their virtual research vessel, players will be able to track their progress, earn badges, read through the game’s field guide, and access educational videos about life on the seafloor.

“NeMO-Net leverages the most powerful force on this planet: not a fancy camera or a supercomputer, but people,” said principal investigator Ved Chirayath. “Anyone, even a first-grader, can play this game and sort through these data to help us map one of the most beautiful forms of life we know of.”

Coral reefs occupy less than 0.1% of the world’s ocean area, but provide a home for at least 25 percent of all marine species (Image: Pixabay)

As they play the game, players’ actions help train NASA’s Pleiades supercomputer at Ames to recognize corals from any image of the ocean floor, even those taken with less powerful instruments. The supercomputer “learns” from the coral classifications players make by hand, using machine learning techniques to classify on its own.

The hope is that data gathered from the game will help researchers find new ways to preserve coral reefs. A new study from James Cook University’s ARC Centre of Excellence for Coral Reef Studies recorded severe bleaching on the Great Barrier reefs during offshore dives in February and March. The study showed that some reefs had 90 percent of their shallow water corals bleached.

NASA is touting the game as both a learning experience along with being an important research tool. The more people who play NeMO-NET, they say, the more accurate Pleiades’ mapping abilities will become. After it has been able to accurately classify corals from low-resolution data included in the game, the supercomputer will be able to map out the world’s corals at an unprecedented resolution. With that map, NASA says scientists can better understand what is happening to corals and find ways to preserve them.

So while you’re currently stuck in your house under quarantine, why not help save the world while you’re at it?

You can play NeMO-NET on an iPad.

Image of Italy's newly discovered mesophotic coral reef. Credit: Scientific Reports.

Scientists discover the first coral reef off the Italian coast

Marine biologists have discovered a new coral reef off the Italian coast in the Adriatic Sea, near the popular touristic town of Monopoli, in Puglia. It is the country’s first coral reef and quite unlike most other reefs due to its unique blend of conditions.

Image of Italy's newly discovered mesophotic coral reef. Credit: Scientific Reports.

Image of Italy’s newly discovered mesophotic coral reef. Credit: Scientific Reports.

Most reefs such as Australia’s Great Barrier Reef or those around tropical areas like the Maldives are vibrantly colored. These sun-soaked reefs owe their dazzling appearance to symbiotic algae called zooxanthellae that capture sunlight and convert it into energy, just like plants, to provide essential nutrients to the corals. In exchange, they have a place to live inside the animal’s body.

However, the new coral reef discovered in Italy is of a different variety. Due to its greater depth, located between 30-55 meters (98-180 feet), the Monopoli reef is mesophotic, meaning it thrives in low light conditions. Instead of photosynthetic organisms, this coral reef is comprised of “non-symbiotic scleractinians”, also known as stony corals. Rather than relying on other organisms for food, the coral obtains nutrients from suspended organic matter floating around the murky Adriatic sea.

“The species composition of the benthic community showed a marked similarity with those described for Mediterranean coralligenous communities and it appeared to be dominated by invertebrates, while calcareous algae, which are usually considered the main coralligenous reef-builders, were poorly represented. Overall, the studied reef can be considered a unique environment, to be included in the wide and diversified category of Mediterranean bioconstructions,” the authors wrote in their study published in the journal Scientific Reports.

Italy's only known coral reef has more subtle coloring than the Great Barrier Reef. Credit: Scientific Reports.

Italy’s only known coral reef has more subtle coloring than the Great Barrier Reef. Credit: Scientific Reports.

Since it doesn’t incorporate algae, Italy’s only known coral reef doesn’t have as many of the colored pigments typically found in other reefs with algae. But that doesn’t make it any less spectacular or appealing to marine life.

“Our barrier lives in dim light and therefore the madrepores constitute these imposing structures of calcium carbonate with the absence of algae,” Professor Guiseppe Corriero, lead author of the new study, told La Gazzetta del Mezzogiorno.

Researchers estimate that the reef covers about two and a half kilometers, but it could very well extend for tens of kilometers along the eastern coast. In the future, they plan on performing more dives in order to find the true extent of the reef.

Coral reefs around the world are threatened by a phenomenon known as coral bleaching caused by warming seas that kill zooxanthellae. Although the newly identified reef does not have symbiotic algae, it is still a fragile ecosystem. This is why Italy’s Regional Council of Puglia is planning to declare the reef a marine protected area.

Australia allows 1 million tons of sludge to be spilled into Great Coral Reef

Remember how a few days ago we wrote about the massive mud plume that hit the Great Coral Reef in Australia? Well, there’s another one headed for it — except this one will come directly from the port.

A plume of sediment off the coast of Queensland after recent flooding. Image credits: NASA.

Despite strict regulation against dumping things in and around the reef, port authorities have found a loophole: the law doesn’t apply to dredging spoils. The Great Barrier Reef Marine Park Authority (GBRMPA) has already given the go-ahead to the Port of Hay Point, home to one of the world’s largest coal loading facilities, to spill up to one million tons of sediment around the reef.

The North Queensland Bulk Ports Corporation, which operates the port at Hay Point, argued in a statement that all the spillage would occur at 100 km away from the reef waters, and will cause minimal damage. However, they agree that the home is area to “coral communities [..] and coastal habitats including mangroves”, as well as “a number of protected fauna species [..] including marine turtles, whales, dolphins, dugong, migratory shorebirds and the Water Mouse,” but argue that the area “does not provide critical habitat for any protected marine species.”

“Importantly, our assessment reports have found the risks to protected areas including the Great Barrier Reef Marine Park Authority and Great Barrier Reef Marine Park and sensitive habitats are predominantly low with some temporary, short-term impacts to benthic habitat possible.”

“Risks to sensitive habitats such coral communities are predicted to be low to negligible as they lie outside of area expected to have altered turbidity and sedimentation.”

However, environmentalists and researchers say this only adds insult to injury, and places the already struggling reef at even more risk.

“The last thing the reef needs is more sludge dumped on it, after being slammed by the floods recently,” Australia Green Party senator Larissa Waters, who hopes to get the permit revoked, tells Smee. “One million tonnes of dumping dredged sludge into world heritage waters treats our reef like a rubbish tip.”

Dr. Simon Boxall from the National Oceanography Centre Southampton echoed similar concerns, saying that it will be difficult to carry out the operation in a way that does little damage to corals. If the material gets too close to the reef, it can smother the corals, and even at large distances, trace metals and other chemicals can still have a damaging effect on the corals.

“If it’s put into shallow water it will smother sea life,” he told the BBC. “It’s important they get it right. It’ll cost more money but that’s not the environment’s problem – that’s the port authorities’ problem.”

Corals, and the Great Barrier Reef, in particular, are under massive threat from rising temperatures and bleaching effects. Studies have also shown that human activity is one of the main reasons why the reef is in decline..

Coral havens might bring worldwide hope for reefs

Understanding how some small pockets of coral reefs are thriving even as the vast majority of their kin is suffering could offer a recipe for preserving coral populations worldwide.

Image credits: Milos Prelevic.

It’s no secret that corals are in big trouble all over the world. Climate change, ocean acidification, and human activity have driven many reefs past the point of no return, with some of the planet’s biggest largest reefs being gravely threatened. Since they’re so vital to marine ecosystems (and also provide great environmental services to us), it’s understandable that scientists are scrambling for solutions to protect the reefs.

Now, an international team of academics has developed a framework identifying small communities of corals that are flourishing against the odds. Focusing on small, key areas in the Pacific and Caribbean, they identified 38 coral “oases” that have escaped, resisted, or rebounded from threats.

The underdog story

It’s not clear why these areas thrive and others don’t — that’s exactly the point. Identifying the reasons for their success and then attempting to replicate them in other areas is a classical approach, which has previously proven successful in some cases, both in biology and in human health.

“There are a number of reasons why one coral reef might survive while its neighbour dies,” said Dr James Guest, a coral reef researcher at Newcastle University who led the study.

“It could be that the location is simply better for survival – deeper water that is outside the storm tracks, for example. The coral communities could possess biological or ecological characteristics that make them more resilient and able to resist damage. Or there may be ecological processes at play which means that the reef community is able to rebound more quickly after a disturbance.”

Study co-author Peter Edmunds, from California State University Northridge, says he was “blown away” by the capacity of the reefs in Moorea, French Polynesia, to rebound following devastation.

“We started working there in 2005, and almost immediately encountered hordes of coral-eating sea stars that quickly consumed the tissue of the corals,” he said.

“By 2010, there was as close to zero coral on the outer reefs as I have seen in my entire career. And yet, within eight years, that coral has regrown. In places, about 80 percent of the sea floor is now covered by live coral. It is a remarkable example of an oasis.”

A glimmer of hope

However, researchers warn, this won’t solve the problems of corals. The identification of these oases doesn’t mean that corals aren’t threatened, or that there is a clear-cut solution that can be applied worldwide. At most, we should be cautiously optimistic — but looking at the greater picture, the dire realism is clear to the eye.

“Coral reefs are in rapid, global decline but the severity of degradation is not uniform across the board and what we have identified are coral reefs that are doing better than their neighbours against the worst effects of climate change and local impacts,” says Guest.

“This glimmer of hope does not mean we can be complacent about the severity of the crisis facing most of the world’s coral reefs. But it does give us a starting point from which to understand why some ecosystems might be more resistant than others and to identify areas that warrant stronger protection or specific management strategies, such as restoration or mitigation.”

The same idea is underlined by Edmunds, who says that the overall situation is very bleak, even with a few very bright spots.

“This does not contradict reports of coral reefs suffering huge losses across the world and that the overall situation is very bad.”

“However, there are kernels of hope in places where corals are doing better, or where they are doing less badly than elsewhere and these places provide us with a focus of attention that might be used to enhance coral conservation efforts.”

Hopefully, these findings can help researchers and conservationists develop successful coral health strategies, but ultimately, it will be up to the policymakers to implement these strategies.

We cannot get complacent and underestimate the environmental crisis we are going through — and we are causing.

Journal References: “A framework for identifying and characterising coral reef ‘oases’ against a backdrop of degradation”, Journal of Applied Ecology (2018). DOI: 10.1111/1365-2664.13179.

Coral reef heart.

The death knell already sounded for coral reefs, it’s time to save anything we can

Coral reefs as we know them are doomed, a new paper reports. What we have to do now is try to save and conserve as much of them as we can — but even experts are at a loss as to how we might accomplish that.

Coral reef heart.

Image via Pixabay.

For decades, marine scientists have been trying to warn us that coral reefs can’t survive in the warmer world we are creating. Those warning calls have peaked and now, they make way for silence. Researchers today watch in stunned despair while the coral reefs as we know them limp their last sickly strides.

A new study published this Thursday, by a team of the world’s top coral experts, comes to sound the death knell of the oceans’ megalopolises. Surveys of over 100 reefs scattered all across the world revealed that extreme bleaching events — which occurred every 30 to 25 years before the 1980s — now take place every five or six years.

A frightful way to go

Corals start bleaching when they overheat. When faced with high temperatures, the host polyps (phylum Cnidaria) have a last-ditch survival strategy — they turn on the symbiotic algae which help feed them (zooxanthellae) and start to consume them alive. The algae that can’t survive the heat or the polyp’s voraciousness get thrown out in a bid to keep the coral as cool as possible.

It’s a desperate shot at survival, a heart-breaking attempt that effectively rips the coral family apart and turns it on each other. It’s ruthless and tragic, but in short bursts, it works. If conditions don’t improve rapidly, however, the wavering algae can’t supply enough photosynthesis to feed the polyp. Starved, the polyp stops its growth and becomes sickly. In the mid-long term, the increase in temperature will kill the corals outright.

Reefs can and do recover from bleaching events. Polyp larvae have no qualms about moving in an unclaimed coral and rebuilding. It does take time, however — about 10 years or so for the fastest-growing corals in a reef — to properly heal.

With the interval between bleaching events shortened five-fold, there simply isn’t enough time for the ecosystems to recover. These damaging events occur so frequently now that the reefs’ chances for recovery in the long term are virtually nil, the authors write. Huge swaths of today’s reefs — which collectively cover an area about the size of France — face almost certain death.

Dead reef.

A bleached coral reef. Image credits: NOAA.

It’s getting worse and worse

“These impacts are stacking up at a pace and at a severity that I never had anticipated, even as an expert,” said Kim Cobb, climate scientist and coral researcher at the Georgia Institute of Technology, not affiliated with the study, in an interview for Grist.

“It’s really the rapidity of it that is so sobering and shocking — and for me personally, life-altering.”

According to lead author Terry Hughes, a coral scientist at Australia’s James Cook University, “mass bleaching of corals was unheard of” before the 1980s.

Since then, things have gone horribly wrong. The paper reports that 94 of the 100 coral reefs the team surveyed have experienced at least one severe bleaching event since the 80s. The remaining six aren’t in a single solid chunk, but they’re scattered across the world — meaning there’s virtually no ocean basin on Earth whose coral reefs have been spared.

Study coauthor and coordinator of the National Oceanic and Atmospheric Administration’s Coral Reef Watch program, Mark Eakin, says that by 2050, ocean temperatures will be warm enough that 90% of all the world’s reefs will experience at least one bleaching event — every year.

“It is clear already that we’re going to lose most of the world’s coral reefs,” he confesses.

And when the corals go, oceans will heave and buckle. We won’t be spared either.

Neptune’s starving trident

Coral reefs provide a slew of essential services for humans and for ecosystems. Despite taking up only 0.1% of the ocean floor, up to 25% of all marine species depend on them for food, shelter, and mating habits. Fish from coral reefs feed over a billion people worldwide, my colleague Elena wrote last year. Those people will still need food — but we won’t have the reefs any longer.

Reefs also rake in billions of dollars every year from tourists visiting coastal areas or island chains to see the “rainforests of the sea”. These reefs will go, or at least change into a very, very different version of their current selves. Conservation biologist Josh Drew, not affiliated with the study, told Grist that the interval between bleaching events is, fundamentally, a “death warrant for coral reefs,” at least  “as we know them”.

“I’m not saying we’re not going to have reefs at all, but those reefs that survive are going to be fundamentally different,” he explains.

“We are selecting for corals that are effectively weedy, for things that can grow back in two to three years, for things that are accustomed to having hot water.”

The economies that today’s reefs prop up will crumble. The societies that depend on them for food will waver, some may not be able to recover. That’s only part of the price humans will pay for coral bleaching.

Right now, researchers are trying to understand what the loss of these linchpin ecosystems will do to the Earth in coming decades. Previous research suggests that the full impact may play out in a domino effect with disastrous consequences. Scientists such as Eakin are desperately trying to save whatever crumbs they still may, considering even “much more radical actions” than they would have previously.

Work is being done to breed genetically-modified super coral species that can live in the warmer, more acidic waters. Other groups are trying to identify the last few dozen reefs that have a shot at surviving. They plan to turn these into seed-banks to be called upon by future generations after climate change has stabilized. Even geoengineering is being considered as a last-ditch attempt to stabilize the climate in time to give reefs a fighting chance.

There’s no consensus on what will work. There’s no agreement on which one is most feasible. But that doesn’t matter because there’s one thing every expert agrees on — the reefs seem doomed, and this is our final shot at saving what’s left.

The paper “Spatial and temporal patterns of mass bleaching of corals in the Anthropocene” has been published in the journal Science.



Reef Snorkelling on the Great Barrier Reef. Credit: Wikimedia Commons.

Coral reefs generate $36 billion in tourism every year but we offer little in return

Aside from supposedly containing the most diverse ecosystems on the planet, coral reefs are an important source of income for many communities around the world. Attracted by their beauty and scientific value, millions of tourists exchange their cash with local businesses, thus supporting many families. Just how much cash? About $36 billion globally, according to what looks like the best estimate so far. Many coral reefs, however, are threatened. If invaluable species that call the coral home don’t impress and spur you to action, maybe hard cash will. Hopefully.

Reef Snorkelling on the Great Barrier Reef. Credit: Wikimedia Commons.

Reef Snorkelling on the Great Barrier Reef. Credit: Wikimedia Commons.

Every year, people around coastlines all over the world collectively make some 70 million trips to visit coral reefs for leisure purposes, according to a team led by Mark Spalding, from the Global Ocean Team and The Nature Conservancy. To gauge how much revenue coral reefs generate, Spalding and colleagues started with national level tourism stats then turning to big data and social media data. No fewer than 20 million public photos posted on Flickr were crawled to assess how popular specific locations were but also to correlate spending around reef sites only. Then, metadata and information like the location of various underwater photos or the bookings from 125,000 hotels were all pooled to further assess spending.

Ultimately, they learned that:

  • business centered around coral reefs is worth $36 billion annually and globally;
  • there are over 70 countries designated as “million dollar reefs” or reefs that generate about $1 million per square kilometer. For many small island states, such revenue stream is critical to their survival being among the few income sources;
  • only 30% of world’s coral reefs are exploited for tourism, the rest being far too difficult to reach, the team wrote in their paper published in Marine Report.

“This data is revolutionizing our view of the world,” says Spencer Wood, Senior Scientist at the Natural Capital Project, in a statement. “We began with 20 million photographs uploaded by the public on Flickr. We mined this information to understand where people are going and we were even able to call out 9,000 underwater photographs taken around coral reefs world-wide.”

As big a financial treasure coral reefs can be, as threatened these are by pollution and, ironically, badly managed and unsustainable tourism. About half of the coral in the Northern Great Barrier Reef are getting killed by man-made global warming, specifically bleaching. Bleaching occurs when the ocean’s waters become too warm and expel the photosynthetic algae, called zooxanthellae, which live in a symbiotic relationship with the coral. Without the algae, the coral dies and seaweeds take over. Just yesterday, the BBC reported Australia’s Great Barrier Reef lost nearly a third of its coral last year alone. In 2017, further coral die-offs are expected from the second year of bleaching in a row, and the impacts of tropical cyclone Debbie, the officials said.

“Of course there are concerns, however the process is not inevitable and no-one is talking about the sudden disappearance of reefs,” said Spalding. “Even if reefs lose some of their vigour they remain vibrant, astonishing places that will continue to attract millions of visitors. What we hope is that these same visitors can create the demand for the best possible management that, in turn, can give reefs their greatest chance of continued good health.”

These findings should serve as a wake-up call for the tourism industry which benefits so much from coral reefs and stands to lose so much if it fails to take action.

“If we can convince the industry to take notice, as they clearly should, our hope is they will step up and support better management of coastal ecosystems like coral reefs. It’s a sort of enlightened self-interest,” says Lauretta Burke, report co-author, and Senior Associate at the World Resources Institute.

Your sunscreen could be killing coral reefs, study finds

Covering your body up with sunscreen may protect you against the Sun, but it’s also threatening the world’s coral reefs, a new study found. University of Central Florida professor and diving enthusiast John Fauth and his team found that oxybenzone, a common UV-filtering compound, is in high concentrations in the waters around Hawaii and the Caribbean, two areas rich in corals. They found that not only does the chemical kill the corals, but it also causes DNA damage in adults and deforms the DNA in coral in the larval stage.

Lathering up with sunscreen may prevent sunburn and protect against cancer, but it is also killing coral reefs around the world. That’s the conclusion of a team of international scientists, which includes University of Central Florida professor and diving enthusiast John Fauth. Credit: UCF: Nick Russett

Coral reefs are threatened as it is. Just two weeks ago, the National Oceanic and Atmospheric Administration (NOAA) raised an alarm about the terrible plight of coral bleaching. For the third time in recorded history, we’re facing a massive coral bleaching crisis, the agency said.

“We are losing huge areas of coral across the U.S., as well as internationally,” said Mark Eakin, NOAA’s Coral Reef Watch coordinator, citing climate change and events like the current El Niño as primary reasons for the mass die-off.

Sadly, this study brings even more bad news to the table; the product they studied is virtually ubiquitous in sunscreen products, and the damage it does is two-fold.

“The chemical not only kills the coral, it causes DNA damage in adults and deforms the DNA in coral in the larval stage, making it unlikely they can develop properly,” a news release reported.

Even very small quantities of the substance can do great damage. They found that the equivalent of “a drop of water in a half-dozen Olympic-sized swimming pools” is enough to cause damage. Executive director and researcher Craig Downs of the non-profit scientific organization Haereticus Environmental Laboratory in Virginia was also involved in the study.


“The use of oxybenzone-containing products needs to be seriously deliberated in islands and areas where coral reef conservation is a critical issue,” said lead researcher Craig Downs. “We have lost at least 80 percent of the coral reefs in the Caribbean. Any small effort to reduce oxybenzone pollution could mean that a coral reef survives a long, hot summer, or that a degraded area recovers.”

To give you a scale of the problem, this isn’t something that only threatens corals. Corals are vital for oceanic ecosystems, and if they collapse, entire ecosystems will collapse with them.

“Coral reefs are the world’s most productive marine ecosystems and support commercial and recreational fisheries and tourism,” Fauth said. “In addition, reefs protect coastlines from storm surge. Worldwide, the total value of coral reefs is tremendous. And they are in danger.”

Many reefs around the world have already taken massive damage, and have almost entirely collapse.

“The use of oxybenzone-containing products needs to be seriously deliberated in islands and areas where coral reef conservation is a critical issue,” Downs said. “We have lost at least 80 percent of the coral reefs in the Caribbean. Any small effort to reduce oxybenzone pollution could mean that a coral reef survives a long, hot summer, or that a degraded area recovers. Everyone wants to build coral nurseries for reef restoration, but this will achievelittle if the factors that originally killed off the reef remain or intensify in the environment.”

So, if possible, try using sunscreen products that don’t have oxybenzone, and for everyday divers:

“Wear rash guards or scuba wetsuits and skip all the hygienic products when you go diving,” Fauth said. “If we could do it for a week at a time, people can certainly forgo it for a few hours to help protect these reefs for our children and their children to see.”

The corals will thank you.


Coral breeding may help reefs survive global warming

20141127_5172_DxO_tonemapped copie

Coral reefs are as important to oceanic ecosystems as they are vulnerable to global warming and ocean acidification. Coral reefs are being destroyed around the world, not only because of risint temperatures, but also due to coral mining, agricultural and urban runoff, pollution (organic and inorganic), overfishing, blast fishing, disease, and the digging of canals and access into islands and bays are localized threats to coral ecosystems. Now, biologists experimenting with coral breeding report some success in maintaining coral populations.

“Coral larvae with parents from the north, where waters were about 2 degrees Celsius (3.6 Fahrenheit) warmer, were up to 10 times as likely to survive heat stress, compared with those with parents from the south,” scientists report.

Corals that naturally thrive in hot, tropical waters can be bred with those that enjoy colder waters to enable the latter to survive rising temperatures. Tests of corals in warm waters on Australia’s Great Barrier Reef found they were able to survive higher temperature rises than those in cooler waters – you basically breed the more vulnerable corals into adaptation and give evolution a slight nudge. The study, conducted by US and Australian researchers gives new hope to dwindling coral populations.

“These mutations are already there, they just need to be spread out,” said Mikhail Matz, an author of the study and a professor of biology at the University of Texas.

[Also Read: Coral Reefs can be saved – but immediate action is necessary]

Corals, despite what most people think, are animals and not plants. They are marine invertebrates that typically live in compact colonies of many identical individual polyps. The group includes the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton. Human impact on coral reefs is significant, and a 2008 study indicated that 19% of the existing area of coral reefs has already been lost, and that a further 17% is likely to be lost over the subsequent 10–20 years. Only 46% of the world’s reefs could be currently regarded as in good health. About 60% of the world’s reefs may be at risk due to destructive, human-related activities. The threat to the health of reefs is particularly strong in Southeast Asia, where 80% of reefs are endangered. By the 2030s, 90% of reefs are expected to be at risk from both human activities and climate change; by 2050, all coral reefs will be in danger. Any idea that might increase their resilience is welcome, but if we truly want to protect coral reefs, we have to come up with a global strategy and limit the damage that we are doing. In the meantime, scientists are doing what they can.

“What I think is the most viable strategy is simply to transplant adult corals – we make a reef and let then cross with the natural corals,” Mikhail Matz, a co-author at the University of Texas at Austin, said in a press release.

But even if they become able to deal with increasing water temperatures, corals still have many other problems to deal with – heat tolerance is not the silver bullet; there is no silver bullet.

Journal Reference: Genomic determinants of coral heat tolerance across latitudes. Groves B. Dixon et al, Science 26 June 2015. DOI: 10.1126/science.1261224

Caribbean Coral Reef

Only one sixth of the original Caribbean corals remain, but damage can be reversed

Caribbean Coral Reef

Photo: The Guardian

It’s estimated that only a sixth of the original coral reef that covered the Caribbean waters is still alive today, according to a recent report released by the Global Coral Reef Monitoring Network (GCRMN), the International Union for Conservation of Nature (IUCN) and the United Nations Environment Programme (UNEP). If no major interference occurs, most of the coral in the Caribbean might disappear in the next 20 years. There are some good news, too. The damage done so far can be reversed, if certain steps are made.

Titled “Status and Trends of Caribbean Coral Reefs: 1970-2012” (full PDF), the report is the result of three years worth of painstaking work that involved over 90 experts who studied more than 35,000 surveys conducted at 90 Caribbean locations since 1970, including studies of corals, seaweeds, grazing sea urchins and fish. Numerous insights that were missed until now have surfaced. For instance, we now know the Caribbean corals have declined by more than 50% since the 1970s.

There are a lot of voices who claim that this immense rate of degradation is mostly due to climate change. Most of the greenhouse gases released by human activity into the atmosphere eventually wind up into the world’s oceans, which act like huge heat sinks. This causes the waters to acidify and the corals to bleach. The report’s findings suggest that its not climate changer per se that is driving most of the coral fallout, rather an ecosystem destabilization. Namely, the loss of parrotfish and sea urchin – the area’s two main grazers – has, in fact, been the key driver of coral decline in the region.

“Even if we could somehow make climate change disappear tomorrow, these reefs would continue their decline,” says Jeremy Jackson, lead author of the report and IUCN’s senior advisor on coral reefs. “We must immediately address the grazing problem for the reefs to stand any chance of surviving future climate shifts.”

These two species are paramount if coral colonies are to thrive, as they feed on algae, clearing the ground so the reef doesn’t get smothered by the algae. But . An unidentified disease led to a mass mortality of the sea urchin in 1983, while extreme fishing throughout the 20th century has brought the parrotfish population to the brink of extinction. Protecting these species from overfishing, as well as pollution, tourism or coastal development will greatly improve reef quality and colony numbers.


A parrot fish a coral. Photo: bugbog

The report also shows that some of the healthiest Caribbean coral reefs are those that harbour vigorous populations of grazing parrotfish. These include the Flower Garden Banks National Marine Sanctuary in the northern Gulf of Mexico, Bermuda and Bonaire, all of which have restricted or banned fishing practices that harm parrotfish, such as fish traps and spearfishing. Other countries are following suit. On the down side, reef that haven’t been protected suffered tragic declines, including Jamaica, the entire Florida Reef Tract from Miami to Key West, and the U.S. Virgin Islands.

“Barbuda is about to ban all catches of parrotfish and grazing sea urchins, and set aside one-third of its coastal waters as marine reserves,” says Ayana Johnson of the Waitt Institute’s Blue Halo Initiative which is collaborating with Barbuda in the development of its new management plan. “This is the kind of aggressive management that needs to be replicated regionally if we are going to increase the resilience of Caribbean reefs.”


Coral Reefs can be saved – immediate action is necessary

Although some scientists suggest that coral reefs are headed for certain doom, a new study by University of Florida and Caribbean has shown that even damaged reefs can recover, but immediate and consistent action is required.

Saving Coral Reefs

Image via by USFWS Pacific.

Corals are very sensitive to environmental conditions. Even slight warming and increased ocean acidification (two processes of which Earth has plenty of these days) can be devastating to them, and despite many efforts, damaged reefs could not be saved. But it’s not all bad news.

In a recently completed 13 year study in the Cayman Islands, researchers reported that bleaching and infectious diseases caused by ocean warming destroyed almost half of a the live coral cover from 1999 to 2004. But only seven years later, the amount of live coral on the reefs, the density of young colonies critical to the reefs’ future health, and the overall size of corals all had returned to the 1999 state.

Most of the area in the Cayman area is highly regulated. Damage from human activities such as fishing an anchoring is minimized.

“Nevertheless, all coral reefs, even those that are well-protected, suffer damage,” Jacoby said. “Little Cayman is an example of what can happen, because it is essentially free from local stresses due to its isolation, small human population and generally healthy ecology.”

So even with global warming and oceanic acidification, if all other human damage is minimized, recovery is possible. Tom Frazer, a professor of aquatic ecology, and Jacoby, a courtesy faculty member in UF’s Soil and Water Science Department, said the study shows even more reasons to protect coral reefs.

Picture via amazipic.

“There’s a debate over how resilient coral reefs are,” said Frazer, director of UF’s School of Natural Resources and Environment, part of the Institute of Food and Agricultural Sciences. “Some say it’s a lost cause. We believe there’s value in making sure coral reefs don’t die.”

The importance of coral reefs

The occupy less than 0.01 of the oceanic environment, but they host up to 25 percent of the different species of marine organisms, yield about 25 percent of the fish caught in developing nations and generate up to 30 percent of the export earnings in countries that promote reef-related tourism. Their safety value is huge, protecting coastal areas against tsunamis and threatening waves, and their environmental value is inestimable.

“In addition to saving the living organisms that make coral reefs their homes, safeguarding the habitats could ensure millions of dollars for the fishing and tourism industries, not to mention maintaining barriers that protect coastal areas and their human inhabitants from tropical storms,” Frazer said.

Via University of Florida.

Tool fish

Fish use tools, video proves!

Tool fishPeople used to think Chimpanzee tool-use was impressive, but it in the past decades it has  been documented that dolphins, whales or birds posses the necessary intelligence to use tools and the environment surrouding them in their benefit. A recent video posted by a professor of ecology and evolutionary biology at the University of California, Santa Cruz, puts things into perspective even further, as it clearly shows a fish using a tool.

Giacomo Bernardi, the biologist in question, was diving with his camera when he caught right in the act a orange-dotted tuskfish as it was digging a clam out of the sand.  The fish then carried the clam over to a rock and threw it against the rock in order to crush it.

“What the movie shows is very interesting,” Bernardi was quoted as saying in a press release. “The animal excavates sand to get the shell out, then swims for a long time to find an appropriate area where it can crack the shell. It requires a lot of forward thinking, because there are a number of steps involved. For a fish, it’s a pretty big deal.”

The footage was shot in Palau and was described by Bernardi it in the journal Coral Reefs.

Evidently, the orange-dotted tuskfish is some what more far witted than its goldfish cousin, and one can only presume that this is far from being an isolated incident. After all the peculiar things we’ve published on this website, you’d think one can become accustomed to all kinds of oddities of nature (oddities to the still ignorant folk that we are). Sorry to say, but not a day goes by without finding myself surprised by all these secrets of life that get unraveled from time to time – some small, some vital. What’s next?

Global warming strikes again: delicate coral-algae partnership threatened

great coral reefAfter things seemed to be going a bit towards the right way, when fishing was banned in the 2nd largest coral reef in the world, a new study pointed out the fact that not a single square meter in the oceans has been left untouched by man’s activities. Corals are especially threatened, and protecting them is vital, as 200 million people depend directly on them to subsist, and several billions are affected by the destruction of coral reefs.

The thing is that between the corals and the zooxanthellae (tiny one-celled plants) is not only powerful enough to create the largest living organism on the planet, the Great Barrier Reef, but also underpins the economies and living standards of many tropical nations and societies who harvest their food from the reefs or have developing tourism industries. The issue is whether this weird yet magnificent partnership is strong enough to resist the threats mankind rises.

Professor David Yellowlees of the ARC Centre of Excellence for Coral Reef Studies (CoECRS) and James Cook University comments:

“It’s an incredibly intricate relationship in which the corals feed the algae and try to control their diet, and the algae in turn use sunlight to produce “junk food” – carbohydrates and fats – for the corals to consume.
“Where it all breaks down is when heated water lingers over the reef and the corals expel the algae and then begin to slowly starve to death. This is the bleaching phenomenon Australians are by now so familiar with, and which is such a feature of global warming.”

“In other words, how robust this symbiotic system is and whether it can withstand shocks from warming, ocean acidification, changes in sunlight levels and other likely impacts from human activity.
“The bottom line here is the survival of the Great Barrier Reef and coral reefs the world over.”

Fishing Ban in the large Coral Reef



Reefs are constituted from aragonite structures produced by living organisms, found in shallow, tropical marine waters with little to no nutrients in the water. A reef is the result of generations of reef-building corals, and not just corals, but also, other organisms. They are take a huge amount of time to form and are fragile – but they are easily destroyed by a number of things.

The importance of coral reefs is humongous. They support an extraordinary biodiversity and are a very important part of our planet. But on the other side, human activity is the biggest danger to the reef and it is intesifying at great rates, threatening to have a catastrophic impact on underwater ecosystems.

The live food fish trade has been implicated as a driver of decline due to the use of cyanide and other chemicals in the capture of small fishes. Finally, above normal water temperatures, due to climate phenomena such as El Niño but more commonly global warming, can cause coral bleaching (the loss of intracellular endosymbionts, without which corals cannot survive). According to The Nature Conservancy, if destruction increases at the current rate, 70% of the world’s coral reefs will have disappeared within 50 years. This would be a disaster for our planet.

apo reef

But a fishing ban around Apo Reef, the largest coral reef in the Philippines and the second largest contiguous reef in the world after the Great Barrier Reef is a thing which is probably going to be a step in stopping the fading of the reef.

“This ‘no-take’ zone will allow the reef and its residents ample time to recover from years of fishing,” stressed John Manul of WWF-Philippines. The reef has 27,469-hectare and it is surrounded by mangrove forest, which serves as a source of food, nursery and spawning ground of several coastal fish and marine species.

“You would hear 25 to 30 dynamite blasts daily,” said Robert Duquil, a former protected area assistant superintendent. “The international diving community lost interest in the area and destructive activities prevailed.”.

“Unfortunately, Apo is plagued by millions of these starfish, probably due to a lack of natural predators like the giant triton, napoleon wrasse and harlequin shrimp,” said Gregg Yan of WWF-Philippines. “We hope that the ban will ensure protection of these predators and the many other reef species.”. The reef needs us and it is our duty to shelter it; or think that without the reef the planet is dying. Look at it how you wish.