Mahale Mountains

Mahale lies on the eastern shore of Lake Tanganyika, in the Uvinza district of Kigoma Region. It was gazetted in 1985 and covers 1,613 km², of which 96 km² is lake: the park runs out into the water along its shore. From the shore at about 770 metres the Mahale range climbs to 2,462 metres at Nkungwe, its highest peak.

The lake is one of the oldest on earth: its central basin began to form 9 to 12 million years ago. It is the longest freshwater lake in the world, at 676 km, and the second deepest, at 1,471 metres, after Lake Baikal in Siberia. It holds at least 250 species of cichlid fish, almost all of them found nowhere else. TANAPA's brochure calls it "the oldest and deepest lake in the world"; that is not right, as Baikal is both older and deeper.

People lived in these mountains long before the park. They were the home of the Tongwe and the Holoholo. The Tongwe Trust, which speaks for the Tongwe today, says they were required to leave the Mahale Mountains in 1973, when Julius Nyerere's government moved rural people into Ujamaa villages. They lobbied for a decade to go back, and that hope ended when the park was created in 1985.

Mahale exists because of Japanese science. TANAPA dates Japanese research here from 1961. In 1965 the young Kyoto primatologist Toshisada Nishida set up at Kasoje, at the foot of the mountains, and planted sugar cane to attract the chimpanzees. It took about six months before they started visiting regularly, and TANAPA dates their habituation from 1966. The research has continued ever since. The only other chimpanzee study begun in the 1960s is Jane Goodall's at Gombe, further north up the lake.

The work changed how chimpanzees are understood. Nishida was the first to show that chimpanzees live in communities with territories, hostile to their neighbours, rather than in family groups. In 1982 his team recorded among wild males the kind of power politics that had just been described in captive apes. The researchers stopped feeding the chimpanzees that same year, and the chimpanzees' aggression towards their neighbours hardly changed.

Two findings from Mahale are still taught today. Self-medication: Nishida saw chimpanzees slowly swallowing whole, unchewed leaves of Aspilia, which give them no nutrition. He and Richard Wrangham published this in 1983, and a chemical with antibiotic properties was later found in the leaves. This work helped found the study of how animals medicate themselves. Culture: in 1975 the primatologists William McGrew and Caroline Tutin came from Gombe and saw the Mahale chimpanzees grooming with their hands clasped above their heads, which the Gombe chimpanzees did not do. Their 1978 paper was one of the first serious arguments that chimpanzee groups have customs of their own.

Nishida pressed the government to protect the area, and he died in 2011. His last book, Chimpanzees of the Lakeshore, was published the following year.

Visitors track the M group, the community studied since the 1960s. It numbered 65 when researchers counted it in 2006. A 2022 study estimated about 3,800 chimpanzees in 2020 across the Greater Mahale Ecosystem, some 18,000 km² of western Tanzania that holds most of the country's chimpanzees. About three-quarters of them live outside the park, in woodland being cleared for farms and settlements, and the population was falling by about 2.4 per cent a year.

Disease is the most direct danger. Chimpanzees catch human respiratory infections easily. Outbreaks swept the M group in 2003, 2005 and 2006. In the June–July 2006 outbreak three infants were found dead and nine other chimpanzees disappeared; up to 12 are thought to have died. A virus related to a human one was found in a sick chimpanzee, and the researchers concluded the disease was possibly of human origin.

That is why the rules are strict. TANAPA's viewing rules are: stay at least 10 metres away; wear a mask, which your guide provides, within 50 metres; do not eat or drink near the chimpanzees; stay away if you are ill; no visitors under 12; no more than six visitors plus a guide at a time; and one hour with the chimpanzees at most.

Other wildlife. TANAPA lists bushpigs, bushbuck, red colobus, red-tailed and blue monkeys and red duiker as easily seen. Along the shore there are ospreys, palm-nut vultures, kingfishers, crocodiles, hippos and otters.

Chimpanzee tracking. You set out on foot with a guide into the forest behind the shore. Finding the M group can take anything from a few minutes to several hours of steep, humid walking, and once you reach them the one-hour limit applies. TANAPA's schedule also lists a Chimpanzee Habituation Experience at Mahale, at USD 100 per adult.

The lake. TANAPA offers boat trips along the shore, snorkelling, diving, kayaking and catch-and-release sport fishing, and fly-camping on the beaches. The water is clear, and snorkelling among the lake's cichlids after a morning with the chimpanzees is the classic Mahale afternoon.

The mountain. The climb to Nkungwe, at 2,462 metres, is the park's big walk. TANAPA says it takes about seven to nine hours to reach the top. Shorter nature trails run through the forest near the shore.

By air. Most visitors come by charter flight to the Mahale airstrip, which TANAPA says is about 5 km from the park headquarters, often on the same trip as Katavi. There are no roads inside the park, so the rest is by boat along the shore and then on foot.

By road and water. TANAPA's brochure gives the road from Kigoma as 220 km, about three and a half hours. By water, you can go from Kigoma down the lake by ship or boat to Lagosa and then take a 30-minute boat ride to the park, or hire a local boat at Rukoma or Mgambo village. The ship on this route is the MV Liemba, which was due back in service after a refit in 2026; see the Kigoma guide.

Fees. Mahale has its own band in TANAPA's schedule: USD 80 per non-East African adult per day, all year, USD 20 for children aged 5 to 15, and TZS 5,000 for East African citizens, all before 18 per cent VAT, so USD 94.40 in practice. Only Gombe costs more. Staying in a lodge or camp inside the park adds USD 30 per night. Boat trips are USD 20, snorkelling USD 10 for up to three hours, canoeing USD 10, sport fishing USD 25 a day, walks USD 20–25 and a park guide USD 20 per group per day.

Staying. TANAPA has self-contained cottages inside the park at USD 40 a night, public campsites at USD 30 per person, and special and fly-camp sites at USD 50. There are also private camps on the shore. TANAPA recommends booking ahead.

When to go. Mahale has two rainy seasons: short rains in October and November, and heavy rains from March to May, with 1,500 to 2,500 mm a year in all. The dry months between, June to September, are the easiest time to walk the forest. TANAPA gives a mean maximum temperature of 31 °C, and it is humid.