Umugisha with her infant Umurage on November 12, 2008 in Amahoro Group.

Last week seemingly punched a hole in my rule of threes.  Another mountain gorilla died in Rwanda—the fourth in two weeks.  I was shocked when Elisabeth, the vet tech for ORTPN, called to say that Umugisha (ooh-moo-gee-sha), an adult female in Amahoro Group, had been found near death.  This was the mother of Umurage (ooh-moo-ra-gee), the infant on whom we’d just done a post mortem.  My immediate thought was that somehow the two deaths must be related.  We think the two-and-a-half year old infant was fatally injured during a fight between the Amahoro Group and wild—i.e., unhabituated– gorillas.  This is bamboo-shoot season in the Rwanda side of the park, a time when interactions among gorillas seem to increase.  We’d heard several reports of habituated and wild groups interacting with each other.  Maybe Umugisha had been injured in the earlier fight and had developed an infection.  Or maybe there’d been another fight since then.

Umugisha resting in the sun with her infant, Umurage, on November 12, 2008.

Elizabeth’s call came at midday on a Friday, reaffirming another rule of veterinary medicine: bad things happen on or just before weekends. It’s rare—in Rwanda, at least, where the monitoring is very good—to get a call about a gorilla that is already dying. Usually we hear from trackers that they’ve found a sick gorilla, and the case starts there. We take a look, make a monitoring or intervention plan, and go from that point. I can think of only two other occasions during my experience here when we were called to check on a dying adult gorilla. Both occurred over a year ago, in 2007.

The first was Umurava, a young silverback from Pablo Group who disappeared for ten days. The trackers found him gasping for air with an infected abscess draining from his neck. He had a pneumonia and air sac infection that had ruptured through to the outside. We knew he was dying. Even so, he was aware of our presence and still capable of fighting back. I anesthetized him and Elisabeth helped me administer emergency treatments. Although he woke up from the anesthesia, he died late the next day. His body had run out of white blood cells to fight the infection.

Not long after Umurava’s death, Jean Felix, Elisabeth and I were called to check on another urgent patient from Pablo Group, an old adult female named Puck. She’d been showing mild signs of indigestion on and off for a few months and then went missing for a day. The trackers found her slumped over and unresponsive, her body pressed against the trunk of a Hygenia tree. She, too, was still very aware of our presence and I didn’t want to stress her. Despite our lightest dose of anesthetic, she died during the intervention. The cause was a combination of cancer and infection. She had a very aggressive form of lymphoma and an abscess that had encircled her entire heart and filled much of her chest cavity.

Umugisha sounded like a similar case. Magda, Jean Felix, Elisabeth, and I rushed to the field with our medical kit. We found the gorilla alive, but barely. Unlike Puck and Umurava who could still respond to human presence with purposeful movement, Umugisha was lying on her back, able only to open her eyes and weakly move a foot or hand. Her condition was so bad that we were able to do an exam, collect samples, and administer treatments without anesthetic.

We examined Umugisha and immediately found the problem: a huge mass in her abdomen. When we palpated below her ribs, we felt the equivalent of three large, hard rocks in the area where we should feel the edge of the liver, spleen, and intestines. The mass could be a chronic infection, but Magda and I suspected cancer. None of us, the trackers included, believed the gorilla would live through the night. Sadly, we were right.

Umugisha grooming her infant, Umurage, on November 12, 2008, two-and-a-half weeks before the infant’s death (November 27) and three-and-a-half before her own (December 5.)

It occurs to me now that Umugisha’s history belongs to a different rule of threes, at least in my own experience of working with mountain gorillas.  Hers is the third case where the patient was so ill that no medicine in the world could save her.  These situations set up a struggle between our hearts and minds.  Humane treatment of animals is a basic commitment for vets.  In private practice or a zoo setting, we would euthanize such a patient, with the consent of owners or zoo staff, and our instinct was to put the gorilla out of her misery.  On the other hand, we manage the mountain gorillas as a wild population, meaning that our mission is to intervene in life-threatening situations only when we believe we can save the animal.  So we did what we could for Umugisha, but chose not to put her through any painful procedures, and left her to die rather than administering a drug to euthanize her.  Though we always review such decisions with all concerned, on the whole most of the park rangers and guides and other officials prefer that we leave animals to die as they would naturally.

Umugisha eating well on November 12, 2008, three weeks before her death on December 5, 2008.

It helps to know that for as long as records have been kept, mountain gorillas have been disappearing from their groups to die on their own.  For example, Pablo, the long-reigning leader of Pablo Group, hasn’t been seen for months, and is presumed dead.  Like many animals, mountain gorillas seem to know when their time is up; they curl up at the base of a tree or under a clump of vegetation to die. There’s no chance for humans to intervene.  This is part of the natural process of life and death.  When habituated animals disappear, the only difference is that we know about it.

Umugisha was indeed found dead the next morning.  On post mortem, we found a huge malignant tumor that involved her diaphragm and stomach.  The mass accounted for a whopping 3.5 of her 57 kilogram body weight.  Once the final results are in, hers will be the third case of cancer found among free-living mountain gorillas.  So far, all have been older females.  The first was a female in DR Congo (before I started working for MGVP), the second was Puck, and Umugisha is the third.  Now we need to review each case to see if they bear any similarity to one another. Maybe we’ll find a new rule of threes.   Meanwhile, we can only hope that our next few patients will be relatively healthy.