The Impenetrable Forest

by Thor Hanson

  I saw the trackers smile with recognition, and Charles thumped his chest with one limp-wristed hand. We closed in slowly on Katendegyere group, and the air grew thick with the pungent, armpit stench that told us the gorillas were nervous. Then another chest beat echoed across the valley, crisp and resonant.

  “That must be Makale or Mutesi,” I whispered to Charles. “Coming to visit Katendegyere. This could get interesting.”

  As if reading from the pages of a gorilla behavior textbook, my two favorite bachelor apes had started to grow more bold. Where Makale and Mutesi used to run at the first sound from another silverback, they now began to seek them out, testing the limits of their new independence and power. The week before, we found them shadowing Mubare group for three days, never confronting Ruhondeza, but staying in the neighborhood and keeping him and his family in a constant, nervous retreat. Eventually, I knew their posturing would lead to a serious encounter, where charges and displays of aggression could attract females to their cause, forming the nucleus of a new gorilla family.

  We moved forward in a tight group, beating a path through the foliage. The forested ridgetops of Rukubira and Hakanyasi rose up on either side of us, leaving a shallow, bowl-shaped valley choked with thickets and copses of tall canopy trees. In a trampled clearing we caught up suddenly with Nyabutono, Kasigazi, and Mugurusi. The “old man” turned and regarded us with a cool stare, his long face inscrutable but calm. Light rain clung to the black hairs of his coat in tiny droplets, reflecting the cloud light in a fine patina of silvery dew. He crossed the clearing in purposeful strides and headed up the far slope with the others close behind. Kasigazi looked large and out of place riding on his mother’s back. At more than three years of age, he was almost fully weaned and independent, but Nyabutono still kept him close when the group was moving quickly.

  They soon drew ahead of us on the hillside, and we decided to head back toward the noise of Kacupira’s chest beats, hoping to witness a rare intergroup encounter. Approaching from above, we found Kacupira and Katome standing guard in a sloping patch of grass and low shrubs. They looked out across the bowl of the valley where the bachelor males sounded off again, closer now, just out of sight behind the trees. I watched Kacupira purse his lips and begin a low croon. The sound rose into a series of soft, chimplike hoots as he reared upright, threw a handful of vegetation into the air, and whacked his chest with four percussive slaps. He then lurched sideways toward Katome and hammered at the ground with both fists. The smaller ape sidestepped Kacupira’s rush and edged up the slope toward us. He paused to feed for a moment, channeling his obvious anxiety into a nonthreatening behavior. The technique can dispel tension in minor conflicts, but Katome hardly even chewed the leaves before continuing past us into the thick brush, following the same uphill route as Mugurusi and the others.

  Kacupira ignored his companion’s departure and crooned the beginning of another chest beat sequence. With nine individual steps, from the vocalization to tearing vegetation, running sideways, and slapping the ground, gorilla chest beats represent one of the most complex visual displays in the animal kingdom. All gorillas imitate aspects of the ritual, and we often laughed at the sight of juveniles like Kasigazi standing upright and thumping their bellies. But only adult males complete the entire display, using it in situations of extreme anxiety or outright aggression. As a precursor or companion to charging, the chest beat can help competing males judge each other’s strength and avoid direct physical conflict. The audible portion alone alerts any other groups or solitary males to a silverback’s presence in the area.

  With Makale and Mutesi approaching from below, Kacupira used the chest beat both to answer their challenge and as a physical outlet for his growing stress. Lunging at Katome had been incidental; his aggression was focused down the hill. I tried to remind myself of this as he retreated quickly toward us across the clearing, hooting, ripping at the shrubs, and preparing for another chest beat. POC-THUD-POC! Even with a lame hand, the noise was powerful five feet away, and I could feel his heavy steps reverberating deep in the ground. He lunged closer but still stared back over his shoulder, looking downhill for his real adversaries. We backed slowly into a thicket as he reared up again, lips parted over teeth like yellowed ivory. Standing nearly six feet tall, Kacupira probably weighed four hundred pounds and looked invincibly strong, but his brown eyes revealed something like panic as the object of his attention finally emerged from the trees.

  Makale strutted into the clearing, stiff-legged, like belligerence incarnate. He looked larger than the last time I’d seen him, with the first gray hairs coloring the saddle of his back. Through binoculars I recognized his nose print and steely glare as he scanned the clearing and advanced slowly into the open. We took advantage of the distraction to scramble farther from Kacupira, but we needn’t have bothered. He took one look at Makale and abandoned his sentry post without a single charge or chest beat, disappearing up the slope behind the rest of the Katendegyere apes. Makale kept up his leisurely, steady pursuit, and we could hear Mutesi bringing up the rear, still out of sight in the trees.

  Heading back to camp in a heavy downpour, we listened for chest beats or vocalizations from the valley, but the gorillas must have sought shelter from the rain, putting aside their aggression, at least temporarily. Katendegyere group would probably continue their retreat, since Mugurusi had nothing to gain from a confrontation; losing Nyabutono to Makale or Mutesi would leave him without a mate, and the rest of his group might well disperse. I returned the next morning and followed the trackers to a wide field of flattened vegetation, site of an obvious confrontation. Trying to picture the encounter, we scanned the ground for signs of blood or fistfuls of hair but found nothing. Apparently, charges and displays had been enough to settle the issue without coming to blows. But the interaction sent Katendegyere group running. Their trail led away in a single-file sprint through the forest as they fled from their persistent, uninvited guests. We counted night nests and knew that the group was still intact, but didn’t catch up with them for two full days.

  20

  The South Side

  Were the gorillas on the three peaks protected I am certain that in a very short time they would become so accustomed to man that they could be studied in their native surroundings in a way that would rapidly produce the most interesting and important scientific results.

  —Carl Akeley

  from In Brightest Africa, 1920

  “Mr. Tour,” Kabahoze Fred called, tapping my shoulder and holding out a chunk of black plastic. “From your boot.”

  “Thanks, Fred,” I said wearily, and tucked the piece into my pocket with the others. Looking down, I saw a new hole near my left big toe. The soles and both insteps were already split, and the front half of the boots flopped open with every step, exposing my wet socks to the mud and thorns.

  This is overdoing it, Jungle Man, I thought, and kept moving up the hill. I should have replaced my leaky rain boots long before setting out on a five-day tracking journey. But that wasn’t my only mistake. At camp the first night, Fred had looked up worriedly from the cook pot.

  “Did you bring salt?” he asked as the others gathered round to eat.

  “No,” I said in growing horror. “You mean we don’t have any salt?” When your only food for five days is boiled beans and corn flour, forgetting the salt is a major culinary setback. The other trackers hung their heads.

  “But…a man cannot live without salt,” lamented Benjamin, turning to Gaston for support. As veteran rangers, they’d both spent countless nights in the forest on antipoaching patrols. But never without salt.

  Gaston only shrugged and carefully pulled out a wild red pepper he’d harvested somewhere, setting it close to the campfire to roast. Laconic and permanently smoky-eyed, he had a reputation as the best woodsman in the park. Watching enviously as he stirred hot pepper into his bowl of beans, I was ready to agree.

  We spent the night near the rushing Kashasha River, at the fo
ot of Kasatoro, an 8,000-foot ridge near the park’s southern boundary. Benjamin, Fred, and Gaston worked as part of our new habituation team, assigned to locate a third gorilla family suitable for Bwindi’s tourism program. We had postponed this phase of the project after the poaching of Kyaguliro group, reevaluating the risks and benefits of habituation. Historically, tourism and research had always helped reduce poaching, logging, and other illegal activities. The daily presence of rangers and trackers drove most hunters away, making tourism areas among the safest in the park. But when that visible protection wasn’t enough, determined poachers would find habituated apes an easy target, as they had with Kyaguliro and the recent slayings in Zaire.

  In the end, the decision came down to fundamentals. Tourism provided Bwindi with revenue, and revenue made the park economically important, both locally and nationally. Losing that incentive posed an even greater threat to gorillas: destruction of the forest itself. We stood by our original concept for the tourism program, that three habituated gorilla families could provide enough income and interest to help sustain the park in perpetuity.

  The challenge now lay in finding a third accessible group. At dawn we drank cups of hot corn porridge and started up Kasatoro’s endless slopes, following a day-old trail of the Nkuringo family, fifteen gorillas named for a dome-shaped hillock halfway up the ridge. The park’s chief warden, Ignatius Achoka, had mapped their range as part of his masters thesis.

  “The place is steep,” he told me, making a vertical line with his hand. “But they should be the closest.”

  Climbing Kasatoro with my boots disintegrating from my feet, I wondered if these gorillas were close enough. Our base camp lay a full day’s hike from Buhoma, and now we’d added seven straight hours of uphill tracking. My legs felt like bent coat hangers, and I’d been doing this kind of thing for two years. Tourists would need a chairlift.

  “The trail is still old,” Benjamin concluded, rising up from a quick examination. “Do we continue?”

  “Sure,” I sighed, and drank from my water bottle. “As long as we can get back by dark.”

  “Down is fast,” he assured me, and scrambled up the path out of sight.

  At last we reached the night nests, a loose group of matted leaf and twig structures tucked into a narrow draw near the ridgetop. We paused to count them, making sure that at least we’d spent our day following the right group. Gaston, Fred, and I split up, marking each nest with an upright branch while Benjamin came along behind to count and measure the dung. He pulled up our sticks as he went, making sure that no nests were counted twice.

  “Fifteen, with four males,” he concluded. “This is Nkuringo.”

  We pressed on, scrambling up an old creek bed as the sun dipped orange toward the west. Scattered clouds threw slow-moving shadows across the ridge, and we hiked through patches of dimness. At this altitude, the forest gave way to frequent clearings, and old rock slides choked with ferns and low shrubs. The noise of our pangas startled up several duiker, spaniel-size forest antelope with tiny straight horns and coats the color of fall leaves. They dashed away in panicky leaps, their nasal alarm cries like shrill whistles or people blowing party favors.

  Moments before I called a halt for the day, Gaston suddenly came to life, scanning the ground with languid interest and moving up for a whispered conference with the others.

  “The gorillas are very near,” Benjamin translated. “If we hurry we can still reach them.”

  I nodded and we picked up the pace, racing against the threat of darkness. Fred took the lead, and I watched him choose our route under Benjamin’s critical tutelage. As the most inexperienced of the trackers, he was still learning about the art of following gorillas.

  Without warning, a silverback charged us from up the slope. I glimpsed a flash of its screaming blackness, and then Fred’s terrified face as he streaked by me, sprinting away down the hill. Never run, I reminded myself, crouching automatically as the gorilla bore down through the foliage. While charging is primarily a display and a bluff, the apes will follow through if their opponent flees, knocking him to the ground from behind. Not surprisingly, most gorilla-related injuries involve a nasty bite to the backside.

  Gaston yanked Fred down as he sped past, and the silverback retreated immediately, disappearing uphill in the dense greenery. We settled into the mud and ferns, waiting for another charge. Suddenly, a swarm of biting flies descended upon us, wave after wave, like nothing I’d ever seen. They covered every inch of bare skin and worked themselves up pant legs, through boot holes, and down our shirt collars. The stinging itch was unbearable, but any sudden movements would only antagonize the nervous gorillas we’d come to habituate. I looked at the others and raised my hands in the universal sign for “You’ve got to be kidding me!”

  Benjamin shrugged back, and Gaston gave me a resigned half-smile as he slapped at the bugs. Fred was too embarrassed by his panicked flight to meet my gaze, and looked sheepishly at the ground while we waited out the attack, wiping tiny flies from our faces and arms like handfuls of buzzing sand.

  I heard faint sounds of movement from up the hill, and we edged slowly closer, but the silverback had already departed, following his family toward the top of the ridge. For the initial stage of habituation, this was a classic response: the rear guard charges while the rest of the group moves quickly and silently away. We had tracked ten hours for a ten-second interaction, but even a single charge was better than no contact. Nkuringo group lacked any experience with people, and only long months of daily repetition would convince them that our presence was benign. Eventually, they might grow calm and curious like Mubare group or learn, like Katendegyere, to anticipate our arrival and actually use it to their advantage.

  On a recent visit, we had found the Katendegyere apes waiting for us at the forest edge, just across the border in Zaire. Kacupira stood at the rear of the group, poised for travel. He looked back at us over his shoulder, barked at the others, and they all took off, racing across a ravine and up into a neighboring banana shamba. Mugurusi led the raid, a line of six sable shadows moving with hurried purpose through the short grass and banana stems. They knew that for the full hour of our visit, they could loot the fields without fear of retribution. With their park ranger friends standing by, no farmers would dare throw rocks or try to chase them away.

  We crossed into the shamba and saw Karema madly stuffing handfuls of banana fiber into his mouth and gulping them down. He didn’t even glance up from his meal as we approached within twenty feet and stood watching. But when two kids from the farm shouted to one another far up the slope behind us, he dropped his banana stem and sat up straight, peering warily over our heads for any sign of the strangers. Seeing nothing, he redoubled his efforts on the feast, chewing frantically until his chin, chest, and forearms were drenched with sticky juice.

  I told that story to Benjamin as we made our way down Kasatoro in the late evening light. He said that Nkuringo group also raided the banana shambas but never let people come close enough to watch.

  “But we will habituate these gorillas,” he assured me with quiet confidence. “It will only take time.”

  I left the Nkuringo trackers hard at work and returned to other tasks in Buhoma. “Come to my obugyeni,” I said in parting, inviting them to my farewell celebration the following month. “We will have matoke, tonto, and even two goats!”

  Benjamin accepted for all of them, then gave me an important tip for the menu. “Salt,” he said solemnly. “This time, don’t forget the salt.”

  21

  The Impenetrable Forest

  …Bwindi has become the main place in East Africa for seeing the mountain gorillas. A major conservation effort has been going on here for a number of years to protect the gorillas’ habitat. As a result, encroachment on the montane forest by cultivators has been stopped, poaching has ceased and the gorilla families have been gradually habituated to human contact…

  —Lonely Planet Guide to East Africa, 1997
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br />   Ruhondeza rolled onto his back and passed gas, a long, raspy sound like the coughing start of an outboard motor. I saw the tourists smile and laugh as they realized what they were hearing.

  “This is common?” whispered a tall man next to me. He spoke in a clipped German accent and sounded offended, as if surprised that such a noble symbol of the wilderness could be capable of flatulence.

  I told him that it happened all the time, one of the less glamorous aspects of gorilla behavior that gets edited out of National Geographic films. With a fibrous fruit and vegetable diet, and their own collection of stomach parasites, mountain gorillas surpassed even Peace Corps volunteers as the gassiest primates on the African continent. As any tracking veteran can tell you, a good portion of gorilla viewing involves sitting around in the rain, listening to the apes break wind.

  We’d found Mubare group feeding on broad-leaved Brilliantasia shrubs less than half a mile from my house. The plants flowered only once every four years, brightening Bwindi’s dim understory with a brief flurry of white, like tiny lanterns in a Japanese garden. The gorillas relished these rare blossoms, but apparently more for their taste than for aesthetic reasons. I watched Ruhondeza pull down a branch and chew lazily at the dangling blooms, like a Roman god nibbling on vine-ripe grapes.

  Lying at the opposite end of the habituation spectrum from the Kyaguliro gorillas, Mubare group had become nearly indifferent to people and sometimes lingered for long periods near the busy footpath that connected Buhoma to villages on the south side of the forest. I’d spent several market-day afternoons escorting groups of fearful locals past the apes, a situation that provided an excellent opportunity for conservation education.