Is coral transplantation the way to save PH corals?
MANILA, Philippines – Is coral transplantation the best way to go about restoring damaged marine ecosystems?
This was one of the questions posed during a Senate hearing on Thursday, April 16, chaired by Senate Committee on the Environment chair Loren Legarda.
The hearing came in the wake of the completion of the biggest coral transplantation project in the country.
Last November 2014, 30,000 coral fragments were transplanted in the reefs of Nogas Island in Anini-y, Antique.
A project of the Department of Science and Technology, the Philippine Army and the local government, the goal was to restore the island's corals to safeguard the livelihood of Antique fishermen.
Fishing is the second largest industry in the province. Abundant oceans depend on healthy and plentiful corals to preserve the balance of marine ecosystems.
Dubbed Filipinnovation Coral Restoration Program, it harnessed the help of the 3rd Infantry Division of the Philippine Army to dive and transplant the corals.
Coral transplantation is the attachment of coral fragments to reefs for them to grow and increase coral cover.
The fragments, detached from their original reef through natural processes (such as strong waves or typhoons), repopulate the reef through asexual reproduction.
In the Nogas Island transplantation site, the army divers gathered the coral fragments and attached them to reefs by hammering them in, using nails and securing them using epoxy and plastic strips.
The surplus coral fragments were attached to metal cages which serve as coral nurseries. When a reef is once again damaged, these fragments may be used for restoration.
The program had to assess two sites: the restoration site, which needed at least 30% coral cover, and the donor site from where the coral fragments were gathered.
The Filipinnovation program, with a funding of P40 million ($900,000), covers 11 sites including Anini-y, the pilot site. This year, the DOST hopes to add another 6 or 7 sites.
Not 'one size fits all'
With such a project about to be replicated, is the method of coral transplantation even worth the funds and effort?
DOST-PCAARRD (Philippine Council for Agriculture, Aquatic and Natural Resources Research and Development) Supervising Science Research Specialist Ester Zaragoza could not yet give the survival rates of the transplanted coral fragments.
The fact that the method uses asexual reproduction makes it easier than the usual sexual reproduction (egg and sperm) but also trickier, said Vicente Hilomen, executive director for Special Programs under the Department of Environment and Natural Resources-Biodiversity Management Bureau (DENR-BMB).
For instance, the Reefbud technology being used to restore corals in top tourist destination Boracay Island, Aklan, at one point involved transplanting coral fragments to artificial reefs.
"It was relatively successful in Boracay for quite some time, for about 4 months. The same technology was brought to Camiguin and instead of coral planulae settling on the reef buds, they were all barnacles that settled there," said Hilomen.
Hilomen added that even in cases when coral did start to grow from the fragments, "in different cases the mortality also is very, very high."
These observations and more led conservation officials and scientists at a coral summit attended by Hilomen to conclude that, for coral restoration method, one size does not fit all.
"We began to realize that there is no single coral technology that can be rolled out for the entire Philippines. One technology can be successful in an area but it cannot work in another area," he added.
The value of corals
Marine biologist Wilfredo Licuanan of the De La Salle University Shields Ocean Research Center said successful coral transplantation depends on "planting" the right coral species in the right areas.
Some coral species thrive in specific depths of water only. Those who wish to use this method must thus be knowledgeable about the species that can survive in the area they want to rehabilitate.
Most people also do not understand that corals are living organisms.
"If you stick one coral species next to the wrong coral species, they might fight and kill each other off," he told Rappler.
Another complication in coral transplantation is the fact that, in many cases, there are not that many detached corals to go around.
Some divers may mistake some coral species as detached when in fact they do not naturally attach to reefs in the first place.
Mushroom corals, for instance, thrive on sand, he said. If a diver were to pull out a mushroom coral and transplant it to a reef, it would not survive.
Another method for coral restoration is through methods based on sexual reproduction.
Male and female corals are made to spawn. The baby corals are then grown in a nursery. When they reach a certain size, they may be transplanted.
But this process is slow. Baby corals may take a month to grow one centimeter or an entire year to grow two millimeters.
Coral restoration can also be expensive, with ranges depending on the method.
Hilomen said that according to a study, rehabilitating corals can cost from P500,000 to P12 million ($11,200-270,000) per hectare.
The Palawan Council for Sustainable Development, he said, spent P800,000 ($18,000) per hectare for coral transplantation.
But experts agree that coral restoration should not replace the primary strategy of preventing corals from being destroyed in the first place.
To do this, critical marine ecosystems should be given adequate protection through laws and strict enforcement, said Legarda.
Much is at stake. Though the Philippines is home to the 3rd largest reef area in the world, only 1% of its coral reefs are said to be in excellent condition, according to Worldwide Fund for Nature. (READ: ARRAS: A new way of looking at coral reefs)
Corals are threatened by destructive fishing practices, natural calamities, and coral bleaching due to warming oceans – a phenomenon blamed on climate change.
Healthy corals have a huge impact on the economy.
According to the DENR, coral reefs contribute $22.9 million (P1 billion) to fisheries. They also provide $46.3 million (P2 billion) worth of shoreline protection. Their contribution to tourism is valued at $2.2 million (P98 million). – Rappler.com