They are of a greyish-brown or earthen hue, and vary from half an inch to one and a half inches in length, and swarm from the ground on all sides. Along the path, on the ends of grass blades and branches of shrubs, they may be seen holding by one end while they reach out their whole length, feeling on every side for prey. The instant they touch the foot or hand, or any part of the body, they take fast hold, and can only be detached by the application of fire, or when they are sated with blood. It is impossible to escape them, the only question being how to mitigate their ravages.
One hundred and twenty years later, the leeches remained almost exactly as Henry described them, though, thankfully, you did not have to burn them. It's easier just to yank them off and roll them between thumb and forefinger until their bodies tear apart, like wet tissue.
Before we reached the leeches, though, there was rice, rubber, sugar cane, and eucalyptus. Departing from Haikou, Bosco and I drove for hours past paddies and plantations. Everywhere the forest was beaten back and kept at bay; where nature wished a jungle, man had sowed a pastoral scene. Peasants in conical straw hats worked by hand, bundling stalks of rice into little teepees or collecting the buckets of latex at the base of rubber trees.
"Hainan is still quite pleasant," Bosco said. "It's very relaxed, apart from the suicidal drivers."
He beeped the horn at every vehicle we passed. On Hainan, honking seemed almost to be a courtesy, warning drivers and bikers of your approach, though Bosco was not above occasionally flipping the bird. Born in Hong Kong, he had attended boarding school and university in England, which he blamed for several of his bad habits. "I like the tropics," he said. "Seven years in England, the weather depressed me. That's why I smoke."
Bosco had first visited Hainan as a boy with his family. Now 37 years old, he had been returning to Hainan almost monthly since 2003 as an employee of Kadoorie Farm & Botanic Gardens, a conservation organization in Hong Kong.
"I know Hainan inside out once we're outside Haikou," Bosco said. We exited the highway and drove into Changjiang, a city whose style (or lack thereof) I would see repeated in Hainan's other cities. Its main road ran between dirt trenches filled with construction materials, as though the city were undecided about the direction its development should take. Across the trenches, confused trees offered shade to merchants sitting by their shops. The architecture was functional and shabby, and the dust rising from the streets browned the buildings. Unfinished construction was scaffolded in bamboo.
We stopped at an "entertainment complex." Some hallways led to movie theaters and karaoke parlors, but we restricted ourselves to the restaurant at its center. There we met Jay, a 25-year-old co-worker of Bosco's from Hong Kong who would join us in looking for the gibbon; and Mr. Li (different from the Mr. Li we had met at the mangrove swamp, and the second of several Mr. Lis I would meet during my time on Hainan), who worked with Bosco on a project near Bawangling. Bosco ordered for me: "Hainan chicken," an island specialty that was, as far as I could tell, just chunks of boiled meat, skin, bone, and an occasional pin feather.
Resuming our journey toward Bawangling, we approached mountains skinned for mining and blighted with pine plantations. The Chinese government established the Bawangling National Nature Reserve in 1980 and banned logging of natural forest on the island in 1994, but by then the damage to the Hainan gibbon was already done.
The Hainan gibbons currently live at altitudes above 3,000 feet; optimally, they would live between 1,300 and 2,600 feet. Bosco and the workers at Bawangling are working to reforest the gibbon habitat down to about 2,000 feet, and so far they have planted 80,000 trees. The hope is that by 2015, those trees will be large enough to support the gibbons and allow mature individuals to form new groups. "If they can find more fruit," Bosco says, "I think they'll shrink their territory to be more in line with other gibbons around the world." (Currently, a Hainan gibbon range is large enough to keep more than 10 groups of, say, Malaysian white-handed gibbons. Smaller ranges would free up space for newly forming groups.)
We arrived at a monitoring station in Bawangling via a half-paved road whose construction went on for so long you'd think they were building another Great Wall. A few men from the gibbon-monitoring team were waiting for us, preparing a lunch of boiled chicken and fatty pork. The station was white with small constellations of blue tiles. The men slept two or three to a room. There was nothing soft or plush about the place, not even a cushion. We lunched on footstools. Then we began our hike toward the base camp in the mountains, where we would sleep in tents that night.
Two steps into the hike, I noticed a leech on the station's lawn. It had climbed onto the lip of a crumpled cup and aimed itself off the edge. It had a moist brown body and a hooked black head, which sniffed about for a warm-blooded passer-by.
I had taken every precaution against leeches: a dousing of bug spray, special socks that tied over my pants beneath the knee to prevent the critters from wiggling up my cuffs. Still, every twig or leaf I brushed against had me slapping myself in panic. Whenever we stopped, I would check my clothing. Usually, they were on my boots, scaling the tongues with freakish determination. They undulated forward, their backs jerking upward like the peaks in a cardiogram. A few minutes into the hike, a shower came down, and I couldn't tell a raindrop's trail from a leech's body.
All around, the leaves nodded in agreement with the rainfall. It was dark in the forest, and the only life I saw, besides the leeches, was a brown toad buried in the carpet of rotting leaves. We crossed several streams, skipping across slick stones. The mountain was not a single, steady ascent, as I had expected, but rather a series of ascending valleys. The gibbons, Bosco explained, might sometimes be only a few hundred yards away, but in order to find them, you would have to plunge into and then climb out of two or three different gullies.
My legs tired quickly from the terrain's alternating demands. Just as my quads adjusted to climbing, the hill would peak, and I would use my glutes to descend the other side. Still, I'm not sure that the hike would qualify as difficult: Bosco smoked cigarettes the whole way; one gibbon monitor wore sandals; and another, our third Mr. Li, carried a live chicken. ("A mascot," Bosco declared, though really it was dinner.)
After an hour, we arrived at a small green shelter in the elbow of a stream—the base camp. A lean-to shaded the shack's right half; beside that, another lean-to covered a cooking pit. The tracking team would sleep in the hut that night. Twenty yards uphill, Bosco, Jay, and I pitched our tents.
We were not quite as removed from civilization as I had imagined: At the base camp, Mr. Li No. 3 talked softly to his girlfriend on a cell phone. Still, we were a world away from the concrete jungle of Haikou. A few gibbon monitors, including a fourth Mr. Li, met us there. Their efforts to find the gibbon that morning had failed.
Bosco, Jay, and I immediately set about checking ourselves for leeches. The back of Jay's shirt had darkened with blood from a bite. Bosco sat barefoot, pruning the insides of his socks. Surprisingly, I was unbitten. When a leech finally got me the next day, the gibbon monitors joked that it would return to its friends to brag that it had drunk the blood of a white man, but in truth the leeches didn't seem to have much of a taste for me.
The men conversed in Mandarin, and I was too anxious and tired to ask Jay or Bosco what they said. We sat around the cabin, waiting for nightfall. Fishing for profundity, I had Bosco ask Mr. Li No. 4 what his first impression of the gibbon had been. "Very cute," he said. It was not the answer I had been looking for, but it pleased me: It was what I expected my own reaction would be.
As it got dark, we ate dinner—boiled chicken and fatty pork, the same as lunch. (It was a feast by their normal standards, but I was a guest.) Two white wax candles lit the table. Someone produced a bottle of baiju, an astringent Chinese grain alcohol. We toasted one another, and the less hardy among us grimaced at its burn. As Bosco and the men discussed business in Mandarin, I began to fall asleep. It was only 7 p.m., but it didn't matter. I was obsessively scanning the ground for leeches, so, rather than torment myself any further, I turned in for the night.