Tag Archives: coral triangle marine protected areas

Repairing Damaged Coral Reefs

Rather than blocking waves, as a sea wall does, a reef slows them, dissipating their energy before they reach land. One estimate, from the University of California, Santa Cruz and the Pacific Coastal and Marine Science Centre, suggests natural reefs prevent $1.8bn a year of flood damage in America alone.

While natural reefs take centuries to grow, hybrid versions can be conjured up in months. The idea began with Wolf Hilbertz, an architect with an interest in marine biology. In the 1970s Hilbertz developed a technique that uses submerged electrodes to run electrical currents through seawater. This precipitates calcium carbonate and magnesium hydroxide out of the seawater, forming limestone similar to that of natural reefs. The artificial reef can become the substrate upon which a natural coral ecosystem develops…Later work with Thomas Goreau, a marine biologist, produced both a catchy name—“Biorock”—and the idea of using the stuff as the basis of coral reefs, and, in particular, for repairing damaged reefs.

In 1996 the Global Coral Reef Alliance, a charity, began using Biorock for reef repairs by growing a six-metre structure in the Maldives. Other repairs have followed in Indonesia, Jamaica and Mexico. The Pemuteran Coral Reef Restoration Project, in Bali, is more than 300 metres long and includes dozens of “nurseries” in which Biorock acts as nuclei for the natural extension of the reef….DARPA a research agency run by America’s Department of Defense, also sees hybrid reefs as a means of coastal defence—in this case protecting the country’s seaside military installations. Lori Adornato, head of DARPA’s “Reefense” project, says the goal is a hybrid reef-type system which will be maintenance-free and self-repairing. Reefense therefore involves not only creating reefs and measuring their effectiveness, but also attracting and fostering appropriate organisms to sustain the reefs’ health, ensuring they can survive even when natural reefs are suffering.

Excerpts from Ocean Reefs: Hybrid Vigor, Economist, Sept. 11, 2021

The Coral Reefs of the High Seas

While the terms “coral reef” and “high seas” are rarely combined in the same sentence, reef-building corals are found in Areas Beyond National Jurisdiction (ABNJ), the high seas. A study that has been published in the Frontiers in Marine Science identified 116 coral reefs in the Atlantic and Pacific Ocean, most of them located outside Marine Protected Areas (MPAs).

There is currently no comprehensive legal framework for the establishment of MPAs in ABNJ. Rather, initiatives to protect critical habitats on the high seas remain scattered throughout the legal mandates of organizations with different management purposes…. Yet, high seas MPAs are possible…. For example, the member countries of the Convention for the Protection of the Marine Environment of the North-East Atlantic (OSPAR) and the Convention on the Conservation of Antarctic Marine Life (CCAMLR) have established MPAs in ABNJ of the North Atlantic and Southern Ocean, respectively While these MPAs provide important advances in protecting biodiversity on the high seas, they still only cover a very small portion of the international ocean. 

David Wagner et al., Coral Reefs of the High Seas: Hidden Biodiversity Hotspots in Need of Protection, Frontiers in Marine Science, Sept. 14, 2020

See also Coral Reefs on the High Seas Coalition

Assisted Evolution: Engineering Coral Reefs

Imagine ecologists cultivating whole new breeds of trees to restock a devastated wilderness…. Coral conservation has traditionally focused on minimizing damage from insults such as water pollution, invasive starfish, and destructive fishing or tourism. In the Caribbean, some conservationists have worked to “replant” damaged coral. But Gates and Van Oppen [two scientists]  have something more intrusive in mind. They want to try to alter the genetics of coral or the microbes that live on it. They dubb the effort “assisted evolution.”

Coral’s most remarkable characteristic—being an animal that is part plant—is also its Achilles’ heel in a hotter world. Normally, coral polyps—the individual coral organisms, which resemble a sea anemone the size of a pinhead—live in harmony with their algal partners, which help feed the polyps and give corals their bright colors. But during heat waves, the relationship sours. Overheated polyps perceive the algae as an irritant and eject them like unwanted squatters. The coral is left bleached, bone-white and starving. If the heat persists, the coral won’t take in new algae and can die.  The bond between coral and algae is complicated, however, and still not fully understood. Just 25 years ago, for example, researchers believed that coral housed just one variety of symbiotic algae. Now, they have identified hundreds. And they are just beginning to examine the role played by the coral’s microbiome, the menagerie of bacteria that inhabit a coral polyp.

Coral bleaching right.

But the complexity also offers multiple paths for scientists trying to forge a less fragile bond between coral and algae. Today, four major lines of research exist: One involves cross-breeding corals to create heat-tolerant varieties, either by mixing strains within a species or by crossing two species that would not normally interbreed. The second enlists genetic engineering techniques to tweak coral or algae. A third tries to rapidly evolve hardier strains of coral and algae by rearing them for generations in overheated lab conditions. A fourth approach, the newest, seeks to manipulate the coral’s microbiome…

In 2018, Cleves [scientist] became the first to report successfully using the CRISPR-Cas9 gene-editing tool on coral. CRISPR is often touted as a method for making genetically modified species. But Cleves says he isn’t interested in creating new kinds of coral. Rather, he sees CRISPR as a tool for deciphering the inner workings of coral DNA by knocking out, or disabling, genes one by one. He hopes to identify genes that might serve as “master switches” controlling how coral copes with heat and stress—knowledge that could help researchers quickly identify corals in the wild or in the laboratory that are already adapted to heat.

Either way, such efforts to re-engineer coral reefs make people such as David Wachenfeld, chief scientist for the Great Barrier Reef Marine Park Authority here, uneasy. The authority is supposed to protect the reef and regulate activities there. In the past, that meant a hands-off approach. Now, he concedes that “it is almost inconceivable that we’re not going to need these tools.” But, he adds, “That doesn’t mean I’m happy about any of this. This is crisis management.”

He ticks off a list of potential difficulties. Scientists focused on breeding heat-loving coral have to avoid weakening other key traits, such as coping with cold. Introducing a new coral on the scale needed to make a dent on a network of 2900 reefs spanning an area half the size of Texas is a daunting challenge. Even in its damaged state, the Great Barrier Reef still contains hundreds of millions of corals—enough to swamp the genetic impact of new coral species…

Could some kind of “super coral,” as some researchers have dubbed them, also run amok in delicate coral ecosystems.

Excerpts from  The Reef Builders, Science, Mar. 22, 2019

Coral Reefs Preservation: Aichi Targets

In the past half-century, though, these beautiful, biodiverse structures have been put under pressure by human activity. About a quarter of all coral cover has died. The reefs that are in worst shape are those off the most crowded beaches. “People don’t leave enough time for their sun cream to soak in, so it gets in the water,” says one deckhand with Eo Wai’anae Tours, which organises boat trips off Oahu. More damage is caused by fertiliser-rich run-off from farms, leading to algal blooms which block light the corals need. Fishing near reefs cuts the number of herbivorous fish, allowing vegetation to grow out of control. Some fishing methods are particularly harmful: for example, blast fishermen in Colombia, Tanzania and elsewhere use dynamite to stun and kill fish without regard to the harm done to nearby reefs…In the South China Seaisland-building and fishing for giant clams are crushing some reefs beyond the possibility of recovery (seearticle)….

Tourism generated by the Great Barrier Reef is worth about $4.6 billion annually to nearby Queensland alone. Australian bigwigs bent over backwards last year to keep the UN from listing the reef, a World Heritage Site, as “in danger”. Estimates suggest that the economic value of Martinique and Saint Lucia’s corals comes to $50,000 per square km each year, thanks largely to tourism. But overdevelopment threatens the reefs the visitors come to gawp at. Sediment from construction clouds waters, burying corals and blocking the light they need. Hotels close to the shore may be convenient for tourists, but the process of building them can kill the reefs that snorkellers like to swim over…The three countries with the largest numbers of people who fish on reefs are all in the coral-triangle region: Indonesia, Papua New Guinea and the Philippines. In Indonesia and in the Philippines, up to 1m people’s livelihoods depend on reefs.

Averting a tragedy of the commons means agreeing which activities should be restricted and enforcing the rules. For coral reefs—and other biodiverse marine environments—the usual approach is to give ecologically sensitive areas special status under local or regional laws. In such “marine protected areas” (MPAs), activities that are deemed harmful, such as fishing, drilling and mining, can then be restricted or banned, with penalties for rule-breakers.

The Aichi targets, agreed in 2010 under the UN Convention on Biological Diversity, seek to reduce “anthropogenic pressures” on coral reefs to “maintain their integrity and function”. The aim is to have at least 17% of inland water and 10% of coastal and marine areas under conservation by 2020. Most countries have signed up. But the targets are far from being met. Less than 3% of the ocean’s surface is within an MPA.

The most urgent action is needed close to shore. The nearer humans are to reefs, the worse their effect on the fragile ecosystems. A global register of fishing vessels, long under discussion, would also help identify wrongdoers. And beefing up the UN law of the sea could inspire further action. Decades old, it has little to say about biodiversity.

But simply declaring an area protected does not make it so. In 2009 George Bush junior, then president of America, established three national marine monuments in the Pacific, including nearly 518,000 square km of coral islands and surrounding areas. Their remoteness makes it hard to stop vessels entering illegally; Hawaii’s coastguard is already stretched.

Satellites are sometimes used to police MPAs, but they pass over infrequently. In the future, sailing robots could play a larger role. America’s National Oceanic and Atmospheric Administration (NOAA) has been working with a private firm, Saildrone, on hardy models equipped with carbon-fibre fins. They cost less than $500,000 each and can roam remote ocean regions for months, making them far cheaper than manned boats.

Such drones could photograph rogue fishing vessels, obtaining hard-to-gather evidence for any criminal proceedings. And they could carry out other useful work at the same time, such as monitoring ocean temperature and acidity or tracking tagged members of endangered species. Saildrone plans to provide its robots as a service, so that universities and other cash-strapped organisations do not have to buy one outright…

Even if the right policies are adopted to keep corals healthy in the immediate future, longer-term threats loom. Neither oceanic warming nor acidification can be kept out by an MPA. And both may be happening too fast for corals to adapt, especially as recent global climate deals will not slow them much. Back slaps and handshakes accompanied the inclusion of an aim to limit global warming to just 1.5°C above pre-industrial levels in the Paris Agreement last year. But only an incorrigible optimist would bet on that aim being achieved.

So researchers are turning their attention to ways to help corals cope. Their global diversity, scientists hope, may hold the key. The same coral will grow differently under different conditions: corals of the western Pacific near Indonesia, for example, can withstand higher temperatures than the same species in the eastern Pacific near Hawaii….The characteristics that help some reefs survive unusual conditions could allow others to endure climate change. But tough corals from one place cannot simply be transplanted to another. So a team at the Hawaii Institute of Marine Biology is in the early stages of engineering reef ecosystems, with $4m from the Paul G. Allen Foundation, a charity set up by Bill Gates’s former business partner.

Organisms respond to environmental changes through both genetic processes (adaptation) and non-genetic ones (acclimatisation). With corals, the nature of their symbiotic relationships can also alter. So selectively breeding and conditioning them, and investigating whether certain types of algae confer resistance to heat or acidity, could create hardier varieties faster than they would develop naturally.

These could then be used to repopulate ravaged reefs—once more is known about how and where to transplant them. “We’re assisting evolution,” explains Ruth Gates, who leads the research.

Marine conservation: Rejuvenating reefs, Economist, Feb. 13, 2016, at 57