"It is a love story," Noah Idechong said as the boat moved slowly through water that was murky but should have been clear. "It is a love story, and the biib is the beautiful girl, and the tree is the boy, and the mother is a giant clam." Then the conversation drifted to why so much silt had clouded the river, and Noah, a prominent conservationist in the area, didn't finish. It was many miles across blue water and through brown water before I learned the full story. It turns out to be a lot like the story of biodiversity on the islands among which I was traveling: beautiful, intense, complex, and troubling.
I met Noah on the island nation of Palau, one of nine independent countries, eighteen territories, and one American state (Hawaii) that make up the Micronesia-Fiji-Polynesia biodiversity hotspot. It is one of 25 areas that Conservation International, an environmental group based in Washington, D.C., has identified as rich in endemic species in danger of extinction. The hotspot includes over 1,400 islands, scattered across an expanse of ocean more than twice the size of the continental United States.
I was heading from west to east across the hotspot and had started in Palau in part because I wanted to meet one of the characters in Noah's story—the biib, the beautiful girl.
In reality the biib is a bird. It's the name that the people of Palau have for a species of fruit dove that lives only in their archipelago. I went looking for the biib and its far-flung relatives because, as descendants of doves that migrated across open water from Southeast Asia, evolving as they went, they are symbols of a scattered but dynamic place. This place is a great crucible, a smithy of life, a place where you can still hear the clang of the hammer of evolution beating out new shapes on the anvil of the world.
But my searching had a wider goal too. The more I traveled here, the more I realized why this place is so important and why it is in danger. As I looked in the branches and listened to distant birdsong, I hoped to find that perhaps there is also an evolution being hammered out here in the human attitude to the Earth's wealth of life.
You can see the importance of this region first in numbers. Fully half of the plants here—3,334 species to be exact—exist no place on Earth but these islands. Strikingly, this high percentage is found on a relatively tiny amount of land. The land surface of this hotspot is only about 18,000 square miles (28,968 kilometers)—less than the area of Vermont and New Hampshire combined.
But these are just numbers. My search for the biib and its relatives took me on a journey where numbers melt in the heat and are washed away by pounding rain and where the uniqueness of one individual tells the story of millions.
I first heard the call of the biib near a lake where I went to swim with jellyfish—intentionally. I did this, well, rash thing because the jellyfish here are a perfect example of the constant restlessness of evolution on islands.
Islands form unique ecosystems mostly because the species that end up living on each island arrived there by chance. So a species that reaches an island will probably find a different kind of neighborhood from the one it left. To survive, the life that's arrived will change to fit the new shape of its niche. In a way, then, each of the 1,400-plus islands of this hotspot is its own factory of evolution. In Palau this quality of islands reaches a wonderful complexity.
Many of Palau's islands are made of ancient limestone pockmarked with sinkholes and porous with caves and tunnels cut by flowing fresh water during past ice ages. At the end of the last ice age, more than 10,000 years ago, glacial ice melted, seas rose, and water percolated through this natural stone plumbing system to fill the sinkholes and create new lakes. The plumbing is big enough that the inland water is salty and responds to the ocean's tides, but is small enough to isolate the lakes from the full panoply of sea life.
"In a way, these lakes are the marine equivalent to the Galápagos Islands. Because of their isolation, they can show how marine species evolve," said Laura E. Martin, a biologist with Palau's Coral Reef Research Foundation who is working with her husband, Mike Dawson, also a biologist, to examine this idea.
To swim with the jellyfish, Laura and I and two of her colleagues boated to an island south of Palau's capital city of Koror. We hiked a few hundred yards through a forest across a sharply eroded limestone ridge, put on snorkels and fins, and swam out into the lake's 86-degree (30°C) water.
I was immediately surrounded by hundreds of pulsing golden blobs. Jellyfish bounced softly off my mask, slid down my arms and legs as I swam, brushed against my neck, arms, feet. There are literally millions of these Mastigias jellyfish in the lake, so there was no escaping their caress. Fortunately they sting so mildly that most of the time it's unnoticeable.
The jellyfish in the lake are not yet identified as a separate species, but over the millennia they have evolved a unique way of life. Every morning they gather at one end of the lake, then migrate in unison across the water, each jelly sunning the gardens of algae that grow within its body and provide much of its food, most swimming close to the shadow line cast by mangroves at the water's edge. In the afternoon they move back across the lake, then descend to deeper water to absorb crucial nutrients.
Why this elaborate ritual? It could be because, unlike similar saltwater lakes here, this one has a robust population of sea anemones along its underwater shoreline. Anemones eat jellyfish, so it's possible that the jellyfish evolved this pattern of clinging to the shadow line to avoid the lake's lethal edge while still maximizing their sun exposure.
In a way this group behavior, seen nowhere else, is a snapshot of evolution in action, a species starting to diverge from its fellows, heading out on an expedition toward something altogether new on the face of the Earth.
On the way back to the boat from the lake I heard my first biib. Its call was a series of hoots strong enough to carry a long way but colored slightly with a tone I found melancholy. Each hoot was shorter than the previous, a cascade of sound that finally stepped down into silence. I looked around, but I couldn't tell where it was coming from.
I was once warned by an ornithologist named Phil Bruner, co-author of A Field Guide to the Birds of Hawaii and the Tropical Pacific, about how difficult it is to find fruit doves by sound. They are almost like ventriloquists, he said: "They're here, but actually they're there."
My search for the biib's relatives soon found me 3,500 miles (5,633 kilometers) southeast of Palau, slogging through rain-saturated pastures among people who I hoped might reveal a relationship to the land older and perhaps wiser than ours.
The place I was trying to reach was the Sovi Basin, considered the last lowland forest on the Fijian island of Viti Levu left undisturbed by logging. Led by a group of villagers, a Fijian botanist named Marika Tuiwawa and I hiked through mud for miles and eventually arrived at a remote camp at the mouth of a gorge. We had reached the basin, but I had yet to see a dove. The ventriloquist call had floated through the trees—here, no actually there—but once again the birds were hidden.
That evening, as the song of another bird, a giant forest honeyeater—a bit like the call of a Manhattan police car in a crowded intersection—announced the coming of night, Marika and I sat in an old hut with the rest of the group. In the hot night the young men lay shirtless on a tarp, some rolling long, thin cigars out of tobacco leaves and strips of old newspaper. These men were still deeply connected to ancient Fijian traditions and the land. All knew how to use the plants in the forest to heal cuts, treat dysentery, or cast or break a spell. When a hunter has not been finding pigs, one of them said, you make a hoop with a vine. When the hunter and his dogs go through the hoop, the bad-luck spirit cannot follow.
Just as I wanted to see fruit doves, so I wanted to hear something from these men about how to save the land. But that hope was also to prove elusive. Though their leaders are working with conservationists to try to find a way to protect the basin from human encroachment, the men with us still had an instinctive sense—so true for human beginnings, so false today—that humans are a tiny presence in the land's grandeur and that individual actions have little power to damage the land's wealth or beauty. It reminded me that what often looks like mere human carelessness is in fact deeply rooted in attitudes that for so long were necessary for survival. They use everything that comes to hand, and because they are few, their actions seem harmless. To float bananas downriver, they cut bamboo for rafts they use just once. And when I asked if there was a place to use for a toilet, the answer was simple: the river.
I come from a more crowded world. I went up into the woods and dug a hole.
I went on looking for doves and hope. Fruit doves made it long ago to Fiji, where three of the islands' species of fruit dove are endemic. Their star is the spectacular orange dove. I hiked on Taveuni in the foothills of the mountain range that makes up the island's long, narrow spine. Deep in the forest I heard an odd tocking sound, something like what you might hear if a small dog were trying to imitate the sound of a clock.
This sound wasn't dove-like. But it was a dove. And this one wasn't a ventriloquist: It was here, and it was really here. All I had to do was look where the sound came from.
Here I was, finally seeing a fruit dove up close. And I didn't believe it. No bird could be this bright; this had to be a gaudy flower or a leaf gone to brilliant orange. But then its head moved. It was, in fact, an orange dove.
The dove sat in the tree's branches, as loud as a used-car commercial. No one knows why this dove's distinctive plumage is so brilliant, whether some combination of mating rituals or camouflage played a role in its evolution. But this much is clear: Once again the uniqueness of a place had brought out the uniqueness of a species and created a living being that could be found nowhere else on Earth.
The orange dove heard me in the shadows and fled. Once it was gone, I couldn't even imagine it anymore.
There is not much land east of Fiji: On a world map the islands there look like scattered grains of sand. Exactly why fruit doves found their way to the Marquesas Islands, a remote piece of French Polynesia almost 3,000 miles (4828 kilometers) northeast of Fiji, is another mystery unlikely ever to be solved.
"Why not other groups? Why not woodpeckers?" Phil Bruner asked, baffled himself about why doves and pigeons have been so successful at dispersing over the Paciffic while other birds from the same source area have not. "The islands are so small that it's hard to believe the birds could even see them from the air to find them," he says.
But they are here. I was not in the Marquesas more than a few hours before I heard my first Marquesan fruit dove, known as the white-capped fruit dove. The sound was almost exactly like the biib, the cascading hoot that still struck me as the melancholy call of the wanderer.
On the island of Ua Huka photographer Tim Laman and I waited under trees on steep hillsides for doves and other birds to feed. Tim focused his attention and big lenses on the endangered ultramarine lorikeet, also known as the pihiti, a bird that both in flight and on a fruit tree seems incorrigibly enthusiastic.
In flight the pihiti dashes along on a fast flutter of wings, calling repeatedly with a sound between a hiss and a trill. When it lands to feed, it clambers all around a mango or a fig, sometimes hanging below the fruit for a quick jab or scrambling on top to sink a dripping beak in the fruit's warm flesh. And everywhere it goes, the pihiti flashes the world a dazzling blueness that brings the essence of the sea right into the treetops.
One afternoon we found ourselves with several Marquesans in a grove of mango trees on the side of a hill. The canopy seemed awash in sunlight, with drips of luminous gold pooling on the ground. The air was dreamy with ripeness from laden branches and rot underfoot.
Once in a while there was a muffled thump as a mango hit the floor of leaves. From far above we could hear both the buzzy trill of the lorikeet and the hoot of the fruit dove. We had glimpses of birds, but mainly they were just rustles in the treetops. They were here, no there, no actually over there! Eventually we all sat down on the aromatic softness of the old leaves while one of the Marquesans chopped the tops off some fresh coconuts with his cane knife and passed them around for us to drink. It was like being inside the fecundity of life itself.
Except for one thing. Like the Palauan story of the biib, this place was not just about love but also about death.
When I finally heard the rest of the story of the biib, it turned out to be grim. It was about a girl and boy who fell in love, but the girl was married to a chief. Then she got leprosy and was shunned. But the boy returned and treated her with a magic herb, which cured her. Yet as they escaped by canoe, the girl's mother plunged into the sea and turned into a giant clam. Desperate, the girl dived in too and drowned.
Noah Idechong had said that the story was somehow a symbol of the relationships of birds and land and sea, and I had hoped for a happy ending. But the story of life in this place doesn't necessarily come out the way we would like.
The threats are familiar: Among them are industrial and urban development, logging, and agriculture, which all lead to habitat loss; the hunting and trapping of native species; the introduction of alien species that compete with the natives or prey on them; and the threat of global warming, which is particularly acute here because if melting ice causes the seas to rise much at all, many islands will shrink or simply disappear.
I saw examples of some of these dangers all along my journey. In Palau I saw silt from construction of a new 150-million-dollar road around the country's biggest island pouring down gullies toward the sea. I drove around with a scientist named Joel Miles, who showed me several species of invasive vines and grasses whose seeds are carried on construction equipment or shoes.
In Fiji I saw a black rat nosing around by a seawall—an introduced species on several of the islands that's a deadly killer to many native birds. On the hike to the Sovi Basin I saw a curious track in the mud ahead of me and asked Marika Tuiwawa what it was, and he said "Mongoose." The mongoose, introduced to kill rats, also wipes out birds by eating eggs.
In the Marquesas, on Ua Huka, I watched goats and horses wandering in search of forage to the highest ridges of the volcanic hills, eating right down to bare ground. And the very appearance of that paradise in the mango grove in which we had been sitting was also a symbol of danger; though not invasive, both the mango and coconut are introduced species. By occupying space and sunlight that native plants once used, such alien species can sometimes compromise the diversity that is so vital to the factory of life.
Because of these things more than three-quarters of the original vegetation in this hotspot has been lost or changed since humans first began arriving here 3,500 years ago. Dozens of birds are now extinct; the list grows longer as archaeologists uncover the bones of hitherto unknown species in the kitchen middens of ancient villages. Some have vanished quite recently.
One of the fruit doves is among them. "Into the 1920s we had the red-moustached fruit dove," said Philippe Raust, a conservationist from Tahiti. "No longer."
And many threats that have not been realized remain poised. The island of Ua Huka, for instance, has a robust bird population partly because black rats have not yet reached its shores. The island's harbor is not deep enough for oceangoing ships, which often carry rats in their holds, to rope up to a wharf on the island; all cargo is first off-loaded onto smaller boats on which rats seldom travel.
Yet the safety is fragile. "If rats got on Ua Huka," says Mark Ziembicki, an ornithologist studying the island's birds, "it would be all over for the pihiti in ten years."
In designating this area as a hotspot, conservationists imply not just that there is something still worth saving here but that there is reason to believe it can be saved. Yet, as I had seen in Fiji, there is not necessarily any great human wisdom waiting to emerge from the past, like an ancient medicine from the bark of a tree, to save us from ourselves. Human beings, like a wandering species that has reached an island of experience unlike anything that it has ever seen, have no choice but to evolve a new behavior—like the jellyfish back on Palau. Maybe, just as the glimpse of the orange dove that for a moment seemed so vivid, a bit of that evolution can be seen here too.
In the Marquesas, Leon Lichtle, the longtime mayor of Ua Huka, told us with pride about protecting a seabird colony by confiscating the boats of those who poached. "The first person we caught was my father," he said, laughing. And Philippe Raust is leading a grassroots effort to save the critically endangered upe, the Nuku Hiva imperial pigeon. "Before people came," Philippe said, "birds were kings of these islands, and the imperial pigeon was king of the birds."
In Fiji I hiked a trail into the mountains with a 61-year-old tour guide named Aisake Tale. His village had a chance to sell forests that contain, among other treasures, kauri trees hundreds of years old. The village turned the money down.
"We say we keep our trees, you keep your money," Aisake said. "To sell to the businessman, you cut it once. But with ecotourism we sell the same tree every trip. Very good."
And in Palau, Joel Miles, the invasive plants specialist, had been delighted when he took me to see a patch of invasive grass and found that members of Palau's bureau of agriculture had taken it on themselves to eradicate it. "I have hope," he kept saying. "This is great!"
Then, also in Palau, there had been the boat ride with Noah Idechong, where I first heard about the biib, the tree, and the giant clam.
Back in 1994 Noah led the development of an activist organization called the Palau Conservation Society; he's since received several conservation awards, including the internationally known Goldman Environmental Prize in 1995 and a Time magazine citation as a Hero for the Planet in 2000.
Noah is now a member of Palau's congress. On a Saturday morning he took me in his boat with several conservationists, including a noted visitor, Margie Cushing Falanruw, director of Yap Islands' Institute of Natural Science. The trip was designed to show the visitors a bay and estuary that have been protected in part because of the conservation society's campaign.
The boat roared through the bay and turned up a tributary. After a while the river grew narrow, and Noah shut down the outboard. The forest seemed peaceful and intact.
But then we heard a rumble in the distance— construction on the new highway. The water was brown with silt that had seeped down from the work sites. We knew that this murky water, bound for the sea, might end up damaging the nearby coral reefs.
"The thing about islands," Margie said, "is that you can see the connections. It's easy to understand the problems on a small island, and that's probably the value of small islands to the whole world."
As we drifted along, we passed a nest a biib had made in an overhanging tree. It was a tiny structure of twigs far out on the slender end of the branch. It was like one of those tooth-pick structures that engineering students make, which look absurdly delicate but create a web of strength. These tiny nests at the ends of branches—beyond the climbing reach of rats—are among the reasons that biibs survive.
Who knows what other survivors there will be? The story of the biib and the tree and the giant clam ended in tragedy, but the end to this one hasn't yet been written.
Somewhere in the woods the biib that had made the nest called distantly, and I looked around, hoping to see her at last. She was as elusive as hope but just as real. She was there, but maybe she was actually here.
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