Abstract

Few mountain gorillas (Gorilla beringei beringei) have ever lived in captivity. A few infants whose mothers were killed by poachers have been rescued, nurtured back to health, and reintroduced to wild gorilla families. Each orphan died or disappeared soon after its return to the forest. After an infant mountain gorilla was confiscated from poachers in December 2004, MGVP, Inc. and their main conservation partners, DFGFI (Dian Fossey Gorilla Fund International), ORTPN (Office Rwandais de Tourisme et Parcs Nationaux), ICCN (Institut Congolaise pour la Conservation de la Nature) and IGCP (International Gorilla Conservation Programme.) formed a scientific committee to make recommendations for the disposition of this gorilla. The partners ultimately agreed to provide short-term housing and veterinary care for orphaned gorillas representing two subspecies-mountain and eastern plains, or Grauer’s, gorillas The cases histories of this gorilla and three additional ones that have since been confiscated show that with proper veterinary care, this species can survive in captivity. But difficult questions remain regarding their future. After living in close contact with people and another gorilla subspecies, they may be carriers of infections not yet identified. Whether or not the orphans exhibit the full range of normal gorilla behaviors is another important consideration. Even if accepted by a wild gorilla family group, their reactions to human visitors may be unpredictable. The partnership has also established an orphaned gorilla scientific technical committee. The committee is considering all options for the orphans, including reintroduction and long-term sanctuary housing.

Introduction

Few mountain gorillas (Gorilla beringei beringei) have ever lived in captivity. A few infants whose mothers were killed by poachers have been rescued, nurtured back to health, and reintroduced to wild gorilla families. Each orphan died or disappeared within a year after its return to the forest.

In December 2004, when Maisha, an approximately 3-year-old female mountain gorilla, was confiscated by Rwandan authorities, the five major mountain gorilla conservation organizations agreed to work together and try a new approach. MGVP Inc. joined a committee with DFGFI (Dian Fossey Gorilla Fund International), ORTPN (Office Rwandais de Tourisme et Parcs Nationaux), ICCN (Institut Congolaise pour la Conservation de la Nature) and IGCP (International Gorilla Conservation Programme). The committee recommended that Maisha be housed with two other gorillas orphaned by poaching that were also under the care of the partners. These were Grauer’s gorilla (Gorilla beringei graueri), a closely related subspecies found only in the Democratic Republic of Congo (DRC). Once Maisha reached adult age and showed her first signs of estrus, the plan calls for her return to the forest in the hope that wild gorillas would accept her as a potential breeding female. The other orphaned Grauer’s gorillas would eventually be moved to a sanctuary, or reintroduced to the wild, in DRC. In the meantime, protocols were put in place to protect Maisha and the other orphans from exposure to disease.

A temporary quarantine facility was completed in Kinigi, Rwanda (the site of the former mountain gorilla veterinary clinic) in January 2007. The two Grauer’s and four additional confiscated Grauer’s orphans eventually became Maisha’s family group, along with seven caretakers and a facility manager. The orphans have been vaccinated for polio, measles, tetanus, and rabies. They undergo routine TB testing, health exams under anesthesia once a year, and regular deworming. Visitors are not allowed, the vet staff visits the facility only when necessary, and the gorilla caretakers participate in MGVP’s employee health program.

Case Report

Maisha has grown substantially and remains generally healthy. However, she and the other orphans have suffered several episodes of respiratory tract illness characterized by malaise, sneezing, and coughing. The disease agents are presumably viral, with secondary bacterial infection, similar to respiratory disease observed in free-living wild mountain gorillas (MGVP research group unpub. data).⁴ Treatments have included extra fluids, expectorants, and antibiotics (amoxicillin, amoxicillin trihydrate/clavulanate potassium).

A second mountain gorilla orphan, an approximately 3-year-old male, Kaboko, was confiscated in March 2007. He presented with severe dehydration and a necrotic, maggot-infested wound at the site of a presumed snare injury to his right wrist. Unfortunately, the hand could not be saved. After amputation and quarantine, Kaboko recovered quickly, joining Maisha and the other orphans in May 2007. He has since developed respiratory tract illness similar to that described for Maisha.

In June and July 2007, two additional orphaned mountain gorillas, Ndakasi and Ndeze, were rescued from the Parc National des Virungas in the DRC after their mothers were killed. Both were infants, estimated at 2 and 6 months old, respectively. They were moved to a private residence dedicated to their care in Goma, DRC. The two orphans are being hand-raised by four caretakers following health protocols similar to those in place at the Rwanda facility.

Shortly after her arrival, Ndakasi suffered a severe respiratory disorder, requiring intensive care with parenteral antibiotics (ceftriaxime), supplemental oxygen, and nebulization therapy for 2 weeks. Clinically, her illness closely resembled influenza or respiratory syncytial virus infection of human infants. Serology results are not yet final.

Ndakasi and Ndeze have grown steadily, despite initial problems with recurring diarrhea. The orphans are bottle-fed commercially available human milk formula and have started eating small amounts of forest food. Initially, their stool color and consistency seemed normal for infant mountain gorillas (i.e., soft, light yellow). Several months later, both orphans developed white, pasty feces. The problem progressed to watery diarrhea in Ndakasi first. Fecal cultures, cytology, and parasitology screening were normal. She developed anorexia and mild dehydration despite oral and subcutaneous fluid therapy. Ndakasi responded immediately to oral antibiotic therapy (metronidazole.). Ndeze developed a similar condition a few weeks later.

The sudden change to watery stool recurred in each orphan, requiring repeat antibiotic therapy (ciprofloxacin.). Fecal Gram stains were initiated on a daily basis. These revealed relatively few bacteria, with a predominance of gram-negative rods and few gram-positive bacteria. The diagnosis was inadequate fecal flora associated with premature weaning and an artificial environment. Because of the ongoing war in the DRC, there was no way to offer the orphans access to gorilla feces which might help establish normal flora. Each was begun on Acidophilus capsules (various brands), mixed in their milk formula twice a day, with excellent effect. Their diarrhea resolved; stool color and consistency changed to normal for 5- to 9-month-old infant gorillas, brown and formed. When the treatment was discontinued, the white pasty stools recurred. The orphans continue on Acidophilus.

Discussion

With proper veterinary care, mountain gorillas orphaned in the wild can survive in captivity. But difficult questions remain regarding the future of the orphans. After years of living in close contact with people and, in Maisha and Kaboko’s case, another gorilla subspecies, the orphaned mountain gorillas may be carriers of infections not yet identified.

Samples collected opportunistically from wild mountain gorillas by MGVP field vets over the years reveal varying degrees of exposure and infection with known human pathogens.^1-6 This result is expected given the large percentage (estimated to be 70%) of wild gorilla groups habituated for research and ecotourism. Initial results from Maisha, Kaboko, and a previous orphan show some pathogen exposure, but analysis of the data for the newly arrived orphans continues (Dr. Chris Whittier pers. comm.)

Whether or not the orphans exhibit the full range of normal gorilla behaviors is another important consideration. Even if accepted by a wild gorilla family group, their reactions to human visitors may be unpredictable.

As Maisha’s potential reintroduction approaches, the orphaned gorilla scientific technical committee will continue to meet and make recommendations for her future-and that of the other orphans.

Acknowledgments

The authors thank all current and previous MGVP field vets, particularly Drs. Chris Whittier and Felicia Nutter who first accepted responsibility for orphaned gorilla care, the orphan gorilla caretakers in Rwanda and DRC, and the rest of the MGVP Africa and US staff.

Literature Cited

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2.  Hastings B, Condiotti M, Sholley C, Kenney D, Foster J. Clinical signs of disease in wild mountain gorillas (abstract). In: Proceedings of the Joint Conference of the American Association of Zoo Veterinarians and the American Association of Wildlife Veterinarians. 1988:107.

3.  Eberle R. Evidence for an alpha-Herpesvirus indigenous to mountain gorillas. J Med Primatol. 1994;21:246–251.

4.  Hastings BE. The veterinary management of a laryngeal air sac infection in a free-ranging mountain gorilla. J Med Primatol. 1991;20(7):361–364.

5.  Lowenstine LJ. Measles virus infection, nonhuman primates. In: Jones TC, Mohr U, Hunt RD, eds. Nonhuman Primates I. Germany, Springer-Verlag Berlin Heidelberg. 1993.

6.  Whittier CA, Nutter FB, Stoskopf MK, Cranfield MR. Seroprevalence of selected infectious agents in free-ranging and captive eastern gorillas (Gorilla beringei). In Preparation.