Sustainable coral nurseries ensure future of Philippine coral reefs

Poverty in the Philippines is mainly responsible for making its coral reefs the most degraded in Southeast Asia and its fishery resources considered the most exploited in the world, despite its recognition as the “World’s Center of Marine Biodiversity.”

The Duka Bay Carbon Cycle Laboratory (CCL) aims to address this threat by using the very people who are responsible for the degradation of our corals reefs to rebuild them, says Ernesto F. Pelaez, team leader of a research group that has been developing a transplantable coral technology over the last eight years.

“The limited sources of planting materials remains to be the main constraint in undertaking massive and wide scale coral replanting,” Pelaez said.

“Because of the abundance of planting materials made possible by our project, we are the first to use Large Coral Clones (LCC) for out-planting. We have developed a methodology to overcome this challenge and in fact are now planting third generation LCCs from our nurseries. The impact is similar to using large planting materials for fruit trees,” he added.

Building on knowledge and experience gained from the previous Asia Pacific Silver Project Awardee “Concrete Substrates for Accelerated Coral Restoration,” this newer initiative seeks to model a “carbon sequestration loop” using existing technology that is affordable, easily replicated and can address issues raised by the Okinawa Declaration on the Conservation and Restoration of Endangered Coral Reefs of the World.

This involves the construction of and installation of concrete substrates seeded with large coral clones (LCCs) that can restore, sustain and expand degraded coral reefs and their associated ecosystems and resources for local communities, fisheries and tourism

It can also establish new coral reefs in barren coastal areas and previously established artificial reefs (ARs) where hard coral recruitment has not been satisfactory.

“Our nurseries are what make us different from previous coral transplantation technologies which source their planting materials from the wild,” said Lemuel R. Alfeche, the team’s resident marine biologist/researcher of the Puka Reef Divers Association.

“The large planting materials we harvest from our nurseries give us an exponentially growing source of corals which also enable the original source of the coral materials to regenerate,” he added.

The project’s carbon fixing mechanism is anchored on the coral polyp’s ability to combine carbon dioxide (CO2) and calcium (Ca) in water to make calcium carbonate (CaCO3) or limestone which is stored in its shell.

This strategy, in time, could significantly absorb carbon dioxide from the atmosphere.

With massive placements of artificial reefs using concrete substrates with large coral clones (LCCs), a quantum reduction of carbon dioxide in the sea and air above it becomes quite a very intriguing possibility.

Such concrete substrates can easily be built and installed by fisherfolk in coastal villages with minimal training. These same people will act as stewards for their ARs which would stabilize, then eventually restore the maritime eco-system in their immediate vicinities. They will serve as guardians of their coastal zones from overfishing, oversee the development of their coastal neighborhoods, and look out for threats to the sustainability of their coral gardens, making them “virtual” marine protected areas (MPAs).

LCCs from nearby “clone nurseries” situated in MPAs will be the key to the long-term sustainability of the projects as the ARs expand and eventually become nurseries themselves to spur even further expansion.

With 17,500 kilometers of coastline, the potential to transform the Philippines’ coral reefs into “rainforests of the sea” as a significant mitigating factor against global warming is mind boggling.

Compared to forest carbon sinks, carbon sequestration in ARs using LCCs have a geometric growth progression, are safe from fire and usual threats faced by land-based forests, with most threats addressable by human intervention, offer permanent/longer carbon sequestration, and are adaptable to sand dunes or barren stretches of seabed, and make it easy to restore degraded coral atolls/reefs.

In contrast, trees can only multiply arithmetically and face environment threats many of which cannot be mitigated by human intervention, and have a relatively short-span carbon sequestration period before they are cut down for lumber or fuel and the decay or burning releases carbon back into the air.

This project aims to make its technology and expertise with artificial reefs using concrete substrates with large coral clones available for the national integrated coastal management plan. It will endeavor to reduce human induced climate change by reducing greenhouse gases, and reduce immediate threats of declining water quality brought by land-use changes and pollution, and mass exploitation of fish biomass.

While it’s true that coral reefs also face similar threats to their sustainability, particularly the increase in sea surface temperatures, decrease in carbonate levels and sea-level rise, caused by increasing anthropogenic CO2 in the atmosphere, whose combined effects stress coral reefs leading to severe bleaching and extensive coral mortality, these respond better to human interventions compared to land based forests.

“However, as of now we can only establish our coral nurseries in marine protected areas (MPA),” said Severo Eduardo M. Yap, PADI open water dive instructor and Pelaez’s partner in the Duka Dive Shop, which is financing the research.

Yap supervised the delineation and zoning of the MPA in Duka Bay, which provided the haven within which to carry out the project free from the depredation of fishermen using illegal fishing methods. The three partners are co-authors of the local and international patent application on the establishment of coral nurseries.

Meantime, the team has developed a superior concrete structure to the original “acanthasia” called the “A-Leg Beam”. The new design reduced by 90 percent the cost of each clone from the 88 clones, which could be accommodated in the giant, eight-legged acanthasia to the 16 clones of the much handier A-Leg Beam.

“The A-Leg Beam is a more dynamic design which allows us to orient it to any position and terrain. It can be placed on top of sandbars, degraded coral reefs, for instance, to initiate coral establishment,” Alfeche said. “Its smaller frame also allows it to either restore a dead reef or establish a new one in a previously bare area, say the “Dive Experience” in the Palm Island Crescent in Dubai.”

The team has documented 150 species of coral in Duka Bay so far, though they acknowledge they lack the time and resources to continue the census. The Philippines, recently recognized as the world’s center of biodiversity, has approximately 300 coral species, 22 of which are hard tropical corals.

Funding for the construction of artificial reefs under this project can be sourced from Annex 1 countries and companies seeking to build up their carbon credits under the Clean Development Mechanism of the Kyoto Protocol.

Although coral sequestration is not yet considered as carbon sinks under the present provisions of the Kyoto Protocol, the project team believes it is only a matter of time before they will be included due to the inherent advantages it offers over the approved methods using land based tree plantations.

Did you find this article useful? Join the EB Circle!

Your support helps keep our journalism independent and our content free for everyone to read. Join our community here.

Most popular

Featured Events

Publish your event
leaf background pattern

Transforming Innovation for Sustainability Join the Ecosystem →