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Heed the Siren’s Call
Efforts to protect the dugongs in south and east Asia, where there are threatened with extinction, bear few results
Dugongs mean everything to Dirk Fahrenbach. He makes a living from taking people to snorkel or dive among dugongs, he married the marine biologist he met during research on dugongs – and he thinks of these most gentle of sea-cows every time he calls his daughter, Serina, the scientific namesake of dugongs. “I hope that my daughter’s children will still be able to see them, but sadly I think they will become extinct one day,” Dirk says. “My only hope is that we can save them here and increase their numbers – there’s always a chance.”
Dirk, owner of the Dugong Dive Centre, is talking about a ten-year dugong protection program that he manages in partnership with Club Paradise, an upscale eco-resort where his dive center is based. Club Paradise is set in Dimakya Island, a private island in Maricaban Bay at the remote northwestern coast of Basuanga Island, one of the islands in Palawan province in the south of the Philippines. The bay is home to nineteen dugongs, believed to be the largest flock in the Philippines.
At the beginning of the program, in 1997, the research was financed by WWF, Toba Aquarium (Japan), and Club Paradise, and led by Janet Uri – now Dirk’s wife. The spin-off to Club Paradise is obvious – dugong-watching tours are a key selling point – and the resort now enforces a fishing ban; two guards armed with M16 combat rifles keep watch round the clock, ready to apprehend or chase off any fishing boat that ventures into the bay. “The ban on fishing applies only for commercial boats,” Dirk explains. “The local fishermen are allowed to fish using hooks and small nets.”
It is relatively easy for Club Paradise to protect Maricaban Bay. It’s remote and virtually unpopulated, ringed by a sweep of empty rotund hills on the landward side and defined by a scattering of tiny isles at the seaward perimeter of the bay, and inhabited only by a few dozen poor fishermen who live in bamboo huts in Maricaban village. “We only found one dead dugong in ten years; it was a juvenile and we couldn’t figure out why it died despite a post-mortem examination,” says Dirk. Yet the herd of dugongs at Maricaban Bay has remained constant, at 19, despite ten years of total protection. “This year we might be lucky,” Dirk says, “as we have four new babies; in all previous years we just had two babies.”
The recovery of dugongs, even in pristine and protected places like Maricaban Bay, is frustratingly slow given the low reproduction rate – females bear their first young at around the age of eight years, and then they have about one sibling every decade, a maximum of six offspring in a lifetime. The animals’ life cycle itself is in slow mode: as herbivorous sea mammals, dugongs consume 25–30kg of sea-grass daily, tearing out the grass in long swoops from sandy sea-beds at a depth of 3–9 meters, growing slowly to a massive 400–500kg, larger than cows. These docile giants spend much of their day eating, their voracious feeding interrupted only by their need for air, surfacing every four or five minutes for gulps of air.
All of this – a large conspicuous animal, the need to surface frequently, and a docile demeanor – makes them easy prey for fishermen, who spear them as they surface, selling their much-sought pork-like meat for 90P per kilo (US$1.70). Another risk for dugongs is entanglement in fishermen’s nests, where they suffocate. Yet the largest long-term threat to their survival is habitat destruction: the pollution and sedimentation that denudes the beds of sea-grass.
The decline of dugongs has been rapid. They were common all over the Philippines until a generation or two ago; now they are present in less than a half-dozen localities, with the largest concentration in Palawan, where the population is estimated at around 250. The story in other parts of Asia, and beyond, largely follows the same pattern of decline. The only stable populations are in the Red Sea and Arabian Gulf, as well as in Australia, which is now their last worldwide stronghold. There are possibly tens of thousands of dugongs in the warm seas in the northern half of Australia, with an utmost concentration in Shark Bay in Western Australia, a protected World Heritage Site, home to an estimated 10,000 dugongs; another 10,000 are scattered along the vast Great Barrier Reef region.
But the situation in South and East Asia is critical, and the sharp downturn in their numbers seems to have accelerated since the 1970s. The animals have been virtually wiped out from India, Sri Lanka, Vietnam, and the Gulf of Thailand. In Thailand they are now limited to a herd of about 150 off the province of Trang on the Andaman coast. In China they are thought to occur only in Hainan Island, and they retain a last foothold in Okinawa Island in Japan – their northernmost range, where they are threatened by developments associated with an American army base. In Indonesia, the number of dugongs has fallen from 10,000 to 1,000 since the seventies.
Everywhere in their range the main threat to their survival is habitat destruction. Pollution (fertilizers, pesticides, industrial runoff) and sedimentation (soil erosion, development, coastal degradation) degrade the sea-grasses on which dugongs feed, and females are known to hold off breeding if insufficient food is present. Then, as populations decrease, the toll from deliberate killing (for meat and hide) as well as accidental suffocation in fishing nets deals further blows to dwindling populations.
“Dugong communities are fragmented and rather small now,” says Bella Sheila Albasin, WWF team leader of another dugong conservation effort in Green Island Bay in Roxas, a couple of hundred kilometers south of Maricaban Bay. Begun in 2001, WWF’s Population, Health and Environment Project is based in Green Island Bay because aerial surveys in the late nineties found nine adults and two calves in the vast bay, one of the largest pockets of dugongs in Palawan. The project is multi-pronged – law enforcement, education, human development, research, and coastal resource management – and its most tangible achievement is the legal protection bestowed on seven dugong-feeding sea-grass areas. Yet Green Island Bay is harder to protect that Maricaban Bay as it’s full of fishermen villages, and large commercial fishes, some of which come from afar, have unfettered access.
“It’s unclear whether dugongs are increasing or decreasing in the bay since we started the project,” Bella says. “We did out last survey, consisting of interviews with fishermen, in 2003. Fishermen told us that in the past they would encounter dugongs several times monthly usually in groups of two or more individuals; now it’s usually sightings of single individuals seen several times a year. We only see one-two individuals when we tour the sea-grass feeding areas.”
Dugongs gained legal protection in the Philippines in 1991. Yet the stiff penalties – fines of up to 500,000P and imprisonment of up to four years – haven’t ended the covert consumption of dugong-meat. A dead dugong is very lucrative for poor fishermen, and last year the WWF team caught four people consuming dugong meat in Roxas; they are currently being charged in court. “It really does not bode well that there are still people who kill the dugong for meat,” Bella laments. “If things continue like this, then we may not see the dugong for much longer.”
Environmentalists fret that, despite stringent environmental laws, law enforcement in the Philippines is inadequate. And devastation of sea-grasses and coral reefs are often contagious; the latter are under relentless assault. Bella thinks that fishing by dynamite and cyanide on the reefs is increasing in Green Island Bay, and she is trying to encourage more rigorous law enforcement by financing the fuel of the patrol boats of law enforcement agencies.
Given the present trends, the situation for dugongs in much of Asia is now critical. As communities become fragmented and isolated, it becomes harder for individuals to meet and mate, and the small pockets of dugongs loose genetic diversity, something that makes them more susceptible to outbreaks of disease outbreaks. No one knows if this point has been reached in the Philippines or elsewhere – it’s a matter of conjectural concern. No one knows the true rate of decline, and Bella has no idea about the impact, if any, of the conservation effort she leads in Green Island Bay.
“It would be great if we can have a population count of dugongs here in Palawan,” Bella elaborates. “But aerial surveys are quite expensive, so we just rely on interview surveys and boat surveys – and we don’t get an accurate population-count from such methods. For the moment, it is heartening that we still get reports of sightings of mother and calf – so they’re still mating and producing offspring.”
(C) Victor Paul Borg 
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