A group of fisherfolk based in barangay Adecor in Kaputian District of Island Garden City of Samal (IGACOS) are trying to save some of the country’s remaining endangered species of giant clams, locally known as taklobo.
The Adecor United Fisherfolk Organization are the caretakers of the giant clams that were transplanted by the Giant Clam Stock Enhancement Program of the University of the Philippines-Marine Science Institute (UP-MSI).
The Marine Reserve Park and Multipurpose Hatchery, as it is called, is under the supervision of the local government unit of IGACOS.
Aside from preventing the disappearance of giant clams in the country’s waters, the organization also helps in raising awareness of the importance of giant clams and providing livelihood opportunities to members and surrounding coastal communities.
They do this through the Taklobo Tours which includes an hour of snorkeling. Visitors are brought by means of a motorized banca from the seashore to the floating cottage, where they are educated about the importance of giant clams.
Once the guests and visitors arrive in a floating cottage, they are given a brief orientation about the conservation status of giant clams, policies, rules, and regulations.
Then, they are given some instructions on what to do while snorkeling. They are told to wear a life jacket and given a snorkel and a mask. After that, they swim to the area where the giant clams are being raised. As the water is clear, they can see the endangered species up close.
Abigail Abigan, of the Internews’ Earth Journalism Network, a first timer in Samal, said she would return to experience it again. Valerie Nuval, a reporter of Vera Files, said it was a completely different world watching the giant clams up-close.
ABS-CBN’s Izzy Lee commented, “The best part of the trip was snorkeling at the Giant Clam Sanctuary on the Island Garden City of Samal. It was beautiful – I wanted to dive instead!”
The three were part of the group of environmental journalists who visited the giant clam sanctuary during the recent Earth Day celebration.
Taklobo Tours started in 2013 and today is one of Samal’s tourism activities.
Actually, the giant clam sanctuary is part of the 14-hectare marine protected area (MPA), also known as marine reserves. These are set-asides designed to balance biodiversity conservation with sustainable use by people.
Taklobo Tours highlights the indispensable role of MPAs in the conservation of giant clam species. It is a community-based ecotourism project whose aim is to promote biodiversity preservation, education, tourism, and livelihood.
“We raise awareness by informing the people who come how endangered these giant clams are and that there are now laws regarding their preservation,” said Joel Gonzaga, one of the members of the organization, and the person in-charge of the tour. “It is now prohibited to harvest them and there are some consequences if they do so – with fines up to three million.”
According to Gonzaga, there are six different species of giant clams in the area. These are Tridacna gigas (true giant clam), T. deresa (smooth giant clam), T. squamosa (fluted giant clam), T. maxima (elongated giant clam) , T. crocea (boring clam), and T. noae (Noah’s giant clam or teardrop clam). The latter is considered a resurrected species, being endemic in the area.
According to a study done by the Davao del Norte State College with support from the Department of Science and Technology (DOST), two species – T. squamosa and T. maxima – are the most abundant species as they are widely distributed around the island.
The four other species are only confined to the western side of the island, close to the giant clams restocking site.
All in all, about 1,500 giant clams were brought by the UP-MSI for possible stock enhancement in the area. Marine scientists have considered farming giant clams as a means of promoting biological sustainability and maintaining biodiversity of the species.
Today, there are 2,906 teeming in the sanctuary.
The giant clam sanctuary is one of those that might be affected by the Samal Island-Davao City bridge once it is operational. There would be an influx of guests coming from Davao City and other parts of the country. Foreigners are most likely to visit Samal as it is known for its beautiful beaches and tourism destinations.
Most of those from Samal are looking forward to the construction of the bridge. “It would be a big boost to the tourism industry of Samal,” said Rem Art Flores, a tourist guide.
Among the envisioned environmental problems that may happen when the bridge becomes operational include water, electricity, and pollution (particularly garbage and plastics).
Going back to giant clams, they are raised along with the coral reefs. Some experts believe giant clams are the key to the country’s endangered coral reefs.
Dr. Cecilia Conaco, MSI’s deputy director of the Bolinao Marine Laboratory, said giant clams build and shape reefs aside from filtering water and recycling nutrients. They also serve as food factories.
Giant clams are the largest living bivalve. Despite their classic movie depictions as “killer clams,” there are no reliable cases of people being trapped and drowned by giant clams. Generally, they occupy coral reef habitats – typically within 20 meters of the surface. They are commonly found in shallow lagoons and reef flats and are characteristically embedded in sandy substrates or those composed of coral rubble.
“The giant clam gets only one chance to find a nice home,” according to a National Geographic report. “Once it fastens itself to a spot on a reef, there it sits for the rest of its life.”
Giant clams also provide shelter for different organisms. Serving as substrates of corals and sponges, marine biologists say giant clams – which can live in the wild reportedly up to over 100 years – help increase the residence of fishes and act as hiding places for other marine organisms.
“Like most corals, some anemones, and other reef organisms, giant clams utilize a combination of methods to obtain food,” explains Oceana, an international group focused solely on protecting the world’s oceans. “The majority of their energy is derived from symbiotic algae living within their cells, providing the clams with excess energy that they make via photosynthesis.”
In return, “the algae have a safe to live and receive the nutrients necessary to photosynthesize. The giant clams provide those nutrients by filtering feeding small prey from the water above the reef surface, which siphons through its body. The beautiful, bright colors characteristic of individual giant clams is actually a result of the symbiotic algae.”
As giant clams cannot literally move due to their heavy weight (as much as 250 kilograms), they reproduce via external fertilization, where eggs and sperm are released into the water column at the same time. Although they are hermaphrodites, they cannot self-fertilize. “They are able to reproduce with other individuals that are close by,” Oceana explains.
Giant clams may have existed even during the time when dinosaurs roamed around this planet. “They have been around for over 38 million years,” wrote Vicky Viray-Mendoza, the executive editor of Maritime Review Magazine. “Antonio Pigafetta, the Italian navigator who joined Ferdinand Magellan in his sea travels around the world, documented these giant clam species as early as 1521 in his journal.”
“We need to do something now before giant clams become extinct,” urges Dr. Rafael D. Guerrero III, a fishery expert and an academician with the National Academy of Science and Technology (NAST).
Dr. Guerrero, however, believes there’s still hope for giant clams. “To save our giant clams, we should protect them in the wild from poachers (particularly foreigners) and promote their sea farming,” he suggested.
