Jacques casually tossed the ball in the air to serve — and smashed it right by me. An ace! That's crazy, I thought, he can't be more than 10 years old. A moment later John-Bosco, at least a year or two younger, slammed a winner past Julie. OK, I felt better. Like me, she's at least 35 years older than these kids.

A tiny boy with a deep voice named Manny kept score. He sounded like a proper umpire. The first few times I heard him call "Fault!" I reflexively looked up for some official sitting in a high chair. As it was, I could hardly see Manny against the glare of the sun; he was standing close to the net post, his head barely above the top of the net. Overall, he did a great job, though I think he lost track a few times.

. One game in particular seemed to go on forever. John Bosco and I had won several points in a row when Manny announced "Trente ans" (30-all). I questioned the score; Manny repeated it with authority. Julie laughed, knowing she and Jacques had gained several free points. But no matter, we were having fun — real fun — possibly the most fun I've had since I arrived in Rwanda.

Thumb01_053107 At one point, Jacques suddenly ran off the court and another boy, Darius, skipped in to take his place. Julie welcomed her new partner and we continued. Apparently it was time for the next lesson on the other court. Every 45 minutes or so, the kids switch, taking their turn with Rachid, the local pro.

Each weekend Julie generously pays for kids in her neighborhood to learn tennis. With a dozen kids, the program lasts all morning on both Saturdays and Sundays. Creative and full of energy, Julie has figured out how to make this work. She gives the tennis kids options: they can sit quietly and watch, or flip through a stack of National Geographic magazines.

.Sometimes she gives them little drills to practice. The first time I visited, I taught several boys on the sidelines how to juggle. Now that they've learned how to keep score and serve, the kids have begun to play doubles on their own when the second court is free.

Julie moved here from Iowa a year ago. She's a graphic artist who loves inspiring others to create their own art — of any kind. Next week we're starting an art project together: drawing classes for the kids of families who live near the gorilla parks. Gradually we'll introduce information about nature, gorillas and health. Even though most of these kids have never seen a wild gorilla they know about them, but we're not sure what, exactly, they know.

Also, thanks to Julie, I've (re)discovered tennis. Until two months ago I hadn't hit a tennis ball for 20 years or so. Work and a busy life, as well as life's injuries, had wiped the game from my list of activities. But it's not easy to get exercise here in Rwanda, and the clay court is soft and slow, which helps. If the gorillas are healthy and I don't feel too overwhelmed by unfinished paperwork (or too sore from trekking up to find my patients during the week), I show up at the courts for an hour or so most weekends.

Until today, Julie and I had played only a set or two with one or two kids acting as ball boys. When she suggested we play mixed doubles this morning, I raised my eyebrows and asked her if she really thought the kids would be OK with it. "Sure," she said. Julie was right — they jumped at the chance.

I'm not sure how Julie got to know these kids initially, but her dogs made the connection stick. Dogs in Rwanda are guard animals, not pets, kept behind walls or tied up. But Julie's dogs live in her house, eat cooked meals and accompany her on walks. Though they're not always well-behaved, they're quite friendly. Even so, they scare the neighbors.

At Julie's invitation — she wanted to help them get over their fear of the dogs — the neighborhood kids started coming by her house to visit, knocking on her gate from time to time. Soon the kids joined Julie on her dog walks. She learned their names and taught them some English. Now, they take the dogs for leash walks on their own. I think Julie started the tennis lessons as a way to give the children a gift — not money or food, but play.

There's no question that tennis is an escape for these kids. They seem happy and carefree on the court, but I know they live a hard life. Most of the people in Ruhengeri town (something like 40,000) are poor, and there's a lot of pressure on children to grow up quickly. Many drop out of school early because they have no choice. They must find work — usually on their family's farm.

Land itself is the most precious commodity here. Because the volcanic soil is rich, even a small patch of dirt is enough to grow a surprising number of potatoes. People own meters of land, not acres.

Walking back from the courts today, I kept thinking about something my friend Perry, a wildlife biologist in North Carolina, said to me years ago when we were working together on a river otter project. "You know, Lucy," he remarked in his soft Southern drawl, "the problem is everyone thinks they own the land. If no one owned the land, there'd be plenty of space for everyone, including them otters." The same holds true for this place — only here it's people and the gorillas

May 30, 2007
The Patients

The trackers found Icyi alone, wet, cold and weak, hunched at the base of a tree. The 3-year-old had been separated from her mother a week earlier after something (probably poachers) scared her family group and caused it to disperse. Without her mother's milk and body heat Icyi could not keep up.

We treated her that day and the next for dehydration and hypothermia, then carried her all the way back to the main group. Sadly, her mother showed no interest and the infant died that night. This was my first field procedure on a wild mountain gorilla, and it taught me a lot — including the painful fact that our patients are often very sick by the time we get to them.

Like Icyi, Agahozo was prematurely weaned when his family group splintered. Mindful of Icyi's death, we observed this little male daily for a week. At 3 and a half years old, he was able to hold his own, eating berries and leaves ravenously, trying to consume enough calories to replace those he would normally have been receiving from his mother's milk.

During this time he developed a swollen face and eyelids. We think the cause was his constant effort to stay warm combined with the loss of energy-rich milk. He also whimpered a lot and stopped playing. After three weeks, Agahozo and his mother were finally reunited. They bonded instantly and now he plays all the time.

Kwakane, a young silverback, lagged behind his group. A green discharge oozed from a wound near his right ear. If this infection involved the gorilla's inner ear canal, it could be life-threatening. We decided to treat him immediately and follow up with an examination under anesthesia two days later if he didn't improve.

Just as I hid the dart gun under my jacket, my heart pounding, Kwakane stood up to take a bite to eat. The flying dart filled with antibiotic hit him in the rear; he reacted as if he'd been stung by a bee and ran away. The next day, he was actively foraging for food and looked much better. We haven't seen him since.

I learned a second painful fact: you can't track a patient's health when he disappears.

Umurava had been in a fight and suffered a torn eyelid on the right side of his face. The young silverback ranked third out of five among the adult males in his group. A few days later he fought again, this time with an aggressive lone silverback. Then he disappeared.

When the trackers finally found him a week later he was near death. He'd suffered a deep wound to his neck and had pneumonia. Once again I found myself trying to help a dying animal. I anesthetized him, but had little hope that my treatments would work. Even if I'd been working in a modern veterinary clinic, rather than on the forest floor, his chances would have been slim. He died late the next day.

Igiti, an adult female, is in good health except for a persistent skin wound on her belly. Though it has improved, the problem will not go away despite two courses of antibiotic treatment by flying dart.

We've decided not to intervene further for a number of reasons. Igiti has an infant, for one thing. She also picks constantly at the wound, a behavior we're not likely to change in a wild animal. Nor do we have a miracle treatment that would resolve the problem under anesthesia. Moreover, Igiti and the silverback who leads her group are extremely wary. We field vets feel frustrated about this case. For now, my plan is just to watch and wait.

Icizere, an adult female with a swollen nose, turned out to be an easy case: she got better on her own. Though we had to drive for more than an hour and hike for nearly three more to get to her, she proved a perfect patient.

Icizere allowed us to observe her closely for minutes at a time. She ate, played a little, rested and glanced at us every once in a while, giving us plenty of opportunities to take photographs. We watched for a nosebleed, something the trackers had reported the day before, but saw no evidence of a continuing problem. I left with the impression that Icizere had simply banged her nose on something — maybe on a low-hanging branch.

Titus is a 30-something silverback, the oldest male among the habituated mountain gorillas in Rwanda. He rests more than the younger males and his ribs are more evident. He remains healthy and in charge — for now. The small wound on his left fourth finger is evidence of a minor scuffle, which he won.

Even so, Titus' age makes him more susceptible to the bouts of respiratory disease that intermittently affect the gorillas. He could develop age-related health problems, like heart disease, tooth infections and cancer. Together with the trackers and researchers, the field vets keep a close eye on this favorite old leader.

Two days before this photo was taken, Makuba, an adult female, had transferred from one group to another. She seemed amazingly calm, though I'd learned from the behavioral researchers that transfers typically get beaten up a bit when they first join a new group.

Sure enough, the next day several females and possibly one of the silverbacks showed aggression toward her. Her long, serene face swelled up with cuts above and below her right eye. But like most social animals, gorillas know how to make a point without causing lethal damage. Makuba healed quickly — a case in which letting nature take its course worked out.

Kabatwa is taking excellent care of her week-old infant, proving she's a good first-time mother. We watched as Kabatwa's baby nursed, held onto her mother with a good grip, and cried when she reached over its head for a piece of bamboo. At one point, the baby opened its mouth and we could see that its gums were a healthy pink.

I couldn't stop smiling during this visit — it's always an amazing experience to watch a mother and infant. But even if the newborn had appeared weak or ill, we would not have necessarily intervened. The dynamics within the group are most important, and it can be very disruptive to attempt treatment on a tiny baby. Luckily, everything looked fine.

We could see something on the face of this 3-year-old female, Ishejekeza, but the light was so bad it was hard to tell exactly what. No matter how minor the case, part of my job as a field vet is adding to the database with a decent photograph.

The playful infant hung on a stalk of bamboo to check us out while we peered at her face. The camera didn't like the dark, however; when I reviewed the image, it looked black. I gave up on photos and pulled out my inexpensive birding binoculars. Now I could see clearly that Ishejekeza's problem was not "gorilla herpes or some other skin infection, but a number of minor cuts and scrapes. (When I downloaded the photos later to my computer, I lightened this one.)

May 29, 2007
Only One Baby, Not Two

My cell phone rang just as we stepped through the break in the stone wall and out of the park. There was a problem with twins in the Kwitonda Group. "Twins?!" I asked Jean Felix (our Rwandan field vet). "Are you sure? That's so rare."

He explained that one had died and one of us needed to go check the mother. He’d tried to call earlier, but reception near the base of Sabinyo Volcano is bad.

I handed the phone to Elisabeth (the park's vet technician). She quickly got the rest of the history in Kinyarwanda and translated the conversation back to me. The babies must have been born overnight. When the trackers arrived first thing this morning, one twin appeared fine; the other dead. I glanced at the sky. Maybe we could get to Kwitonda before the coming deluge.

The hike to Sabinyo Group had taken about an hour from the wall — a relatively short trek. We'd found the gorillas at low altitude — about 2,700 meters (8,500 feet) — eating bamboo near their night nests. They looked fine, as expected for a routine health check. The trackers reported that one female seemed a bit slow, though. We watched her stuff her mouth full of green plant material, and noticed her belly looked a bit round. Maybe she was pregnant.

This wasn't the first time Elisabeth and I had found ourselves hiking down one mountain only to find ourselves going up another, and it probably wouldn't be the last. Luckily, Jean Felix told us that the Kwitonda group was close. Elisabeth and I would go have a look, and he could bring our field kit if necessary. Unless the mother was severely ill or injured, we wouldn't intervene with a newborn baby. Nature often takes its course here.

I nearly stumbled on the silverback, Kwitonda. (Gorilla groups are named for the dominant male, called a silverback.) The group was indeed not more than five minutes walk from the wall. He sat with his back to us, eating. Nearby, several infants and juveniles were digging at the base of a fallen tree, stirring up flies and making a mess. The new mother, Mugeni, had her back to us in some bushes beyond the group of playful youngsters.

Before we could get our cameras ready, Kwitonda wandered away toward an area of fresh vegetation. Several gorillas followed, including Mugeni. She lifted an infant by the arm, then held it close to her body on the right side. The baby was fully-haired and looked like a normal full-term infant, its mouth hanging open. I couldn't see the second baby.

We waited until the gorillas repositioned and settled. This time, Mugeni chose to sit down facing us. Thin vegetation surrounded her, but now we could see both infants, each in the crook of an elbow. The light was fading fast thanks to the approaching storm. This might be our only chance to get a look at the gum color of the live infant and to see the condition of the dead one. Once the rain came, the gorillas would take cover.

I focused my binoculars. At first I couldn't be certain which infant was which. The head of the one on the right had curly hair; the other's looked smooth, as if freshly combed. Then the mother repositioned the infant in her left arm. It raised a tiny hand and grabbed the skin near her breast. She moved again, holding the body of the second infant close to her right side. It didn't move. The one on the left opened its mouth and yawned.

I saw bright white teeth and pink gums. It reached for its mother again. When Mugeni moved her right arm, we could no longer see the dead infant and guessed she’d let it fall to her lap, which was hidden from us by vegetation.

I offered the binoculars to Elisabeth, pulled out my camera and began clicking away, hoping to keep ahead of the rain and get at least one decent picture.

Kwitonda moved again, but slowly, leading the group a little farther into the bamboo. He sat down again to eat. Some groups have more than one breeding male, but not this one. Kwitonda is definitely the father of these twins. I'd seen behavior like his before. The silverback takes things easy when there's a new infant, as if he understands the new mother needs a rest and a bit more time to feed herself and the infant.

"Yes, the chief knows. It's normal for him not to move very far," Elisabeth agreed. Though trained as a technician, she's as much a doctor as any of us. She knows these gorillas. I learn something new from her every day — about the animals, the people, the country and the language.

Huge drops of rain suddenly poured from the sky. We discussed the situation briefly. Mugeni would carry the dead infant for several days, maybe longer. She might leave it behind during a feeding session, or in her night nest; we'd ask the trackers to stay close to her for the rest of the day and try to find her sleeping place first thing tomorrow. If we could recover the body, we might learn what had gone wrong.

I worried that the living baby had to share its mother's chest with the rapidly decomposing body of its dead twin. Bacteria or fungi could start growing in its tissues, exposing the healthy newborn to a load of organisms. Its immune system wasn't even 48 hours old. But there was no action we could take.

Elisabeth and I traded a few more thoughts, yelling above the noise of the downpour. Mountain gorillas rarely have twins, and only one pair has ever survived (they're in the Susa Group and about to turn 3 years old.). This twin had undoubtedly died as a result of birth injuries. Perhaps Mugeni simply hadn't been able to break the umbilical cord and stimulate both infants to breathe in time. If so, it had been a natural death and we saw no reason to worry about a health problem in the mother or the surviving infant. One of the vets would come back the next day to check again.

As we turned to leave the forest, I smiled and said to the trackers, "Congratulations, you may not have two babies, but you have one and it looks great. A new baby is always a good thing!" Elisabeth nodded, translated some portion of my statement and we said our goodbyes. I'd see the trackers again tomorrow.

May 22, 2007
Into Rwanda

Seconds after our guide whispered, "We are close," a silverback emerged from a shadowy patch of bamboo. It was November of 2006 and I was seeing the animals for the first time as a tourist, before starting my new job in Rwanda as regional manager of the Mountain Gorilla Veterinary project. I'd had plenty of experience with gorillas in zoos — behind bars. I took a step back. The silverback glanced casually at me and moved on, sitting down to a meal of greenery.

Susa Group Family

Later in the hour-long visit, one tracker realized I was the new gorilla doctor. He led me carefully through the bamboo and sat me down several feet away from a female gorilla with an obvious wound on her belly. As I focused my camera on the injury, I heard rustling and a few grunts. The rest of the family was playing nearby. "Wow," I thought, "I am in their world, and they don't mind. "

Every visit to the gorillas is an amazing experience. On this morning, for instance, we reached a group before they left their night nests. We'd come to check on a newborn infant. While we waited patiently for the new mother to wake up, a curious 2-year-old inched a bit closer to check us out. We inched away, maintaining at least a 20-foot distance. I took this photo with the camera on max zoom.

Lucy at work in Rwanda's Volcanoes National Park

My friend Winnie, one of the scientists who studies mountain gorilla behavior, took this picture. I was smiling because we were finally headed down the mountain after a particularly cold, wet observation period. I'd dug out every item of clothing I had in my bag and layered it on — even a hat. This job offers many wonderful things, but glamour is not one of them.

Stinging Nettle, Volcanoes National Park

There's another reason for multiple layers of clothing at work: the stinging nettle, "ortie" in French, and "igisura" in Kinyarwanda. I've learned a new skill: how to navigate uneven, slippery ground and avoid getting hit in the face by the nettles. My success rate, however, is far below 100 percent. Amazingly, the gorillas eat this plant!

The view from the Visoke Volcano

After one cold night, we awoke to see snow on the mountaintops. I imagined the gorillas huddling to stay warm. The Volcanoes National Park — the gorilla park — is located in the Virunga Massif, a chain of ancient volcanic mountains along the shared border of Rwanda, Uganda and the Democratic Republic of Congo. Mikeno is still active; it even glows at night.

Some of the mountain gorillas live apparently normal long lives despite old injuries. No one knows what happened to this adult female. When her group was first habituated for tourism, the trackers noticed that her left hand was missing. Given the history of poaching in the area, we think she probably lost it to a snare.

The name "gentle giant" fits these animals well. The silverback, also called the chief (le chef), allows his family to play all around him. Smaller infants often use his 400-pound body as a prop in their games. The chief tolerates our presence, too. If he didn't, I'd be out of a job. We intervene only when there is a life-threatening health problem. The rest of the time, we watch.

Most of the people who live in Kinigi, the town nearest the gorilla park, are farmers. Though few — perhaps none — have ever seen a mountain gorilla, they are aware of their upland neighbors. Here, the pygmy tribe known as Batwa perform a dance about gorillas accompanied by expressive singing and drumming.

A domestic cow near Sabinyo Mountain

We consider diseases carried by any animal — whether humans, cows or other species —potential threats to the fragile mountain gorilla population of just 700 animals. The threat from tuberculosis, for example, is the main reason commercial farms pasteurize milk. But many Rwandans dislike the taste of boiled milk. To date, tests show there is no TB in the cows near the gorilla park, but it may just be a matter of time.

Topi Antelope, Akagera National Park

Though Rwanda is only about the size of the state of Maryland, its geography varies greatly. Akagera National Park sits close to the border with Tanzania, only a four-hour drive from the misty volcanoes where my office is headquartered. Once in a while I have to remind myself how much animal life there is to see in this country, like the topi antelope pictured here.

This sunrise could be happening any number of places in the world where there are mountains. The misty blue tinge reminds me of one of my favorite places, the Blue Ridge Mountains, where my mom lives in North Carolina.Though I miss my family a lot, including my Labrador retriever, I know this job is a once-in-a-lifetime opportunity.