Tuesday, April 2, 2013 |
The Serengeti, located in the northern part of Tanzania and southwestern Kenya, is one of the world's most important ecosystems. The huge grassland is home to a huge diversity of the wildlife we associate with Africa: lions, zebras, rhinos, leopards and giraffes. But the region's keystone species is the wildebeest, which migrate in their millions across the great plain.
Dr. Anthony Sinclair, professor emeritus of zoology at the University of British Columbia, began studying the Serengeti, and the wildebeest in particular, in the 1960s while still a student at Oxford. The region became both his life's passion and work. He has chronicled both in his new book Serengeti Story: Life and Science in the World's Greatest Wildlife Region. In a recent interview with Quirks & Quarks, he talked about what makes the Serengeti unique, and the challenges it faces.
Sinclair told host Bob McDonald that the Serengeti is an important ecosystem because of its unique combination of geographic circumstances, "with mountains in the east creating desert conditions, and Lake Victoria, the third largest lake in the world, in the west, which creates wet conditions." The resulting gradient of rainfall leads to a migration. It's also an area of high productivity, so there are very large numbers of animals.
The wildebeest number more than a million and have a huge impact on the ecosystem. "They essentially take most of the resources, most of the energy, most of the food," Sinclair said. "Everybody else has to make do."
In his book, Sinclair describes some of the hair-rising encounters he has had there. "We had one incident where lions decided they were going to kill a buffalo. The buffalo took refuge on our veranda. I was not aware of this, first thing in the morning, and I walked straight into it," he said. "Needless to say, I beat a hasty retreat."
He actually feared for his life on two occasions: once when confronting bandits armed with poisoned arrows, which Sinclair said "are a lot more dangerous than bullets, because you only have to be grazed by one and you're in trouble," and another when he was being trailed by a pack of hyenas.
Despite the dangers, Sinclair stayed because of the wonders of the Serengeti. "You go out on those plains, when all the wildebeest are there, you can drive for 80 kilometres and have wildebeest from horizon to horizon non-stop," he said. "It is so astounding that every time I see it, I realize it is breathtaking, and that's what keeps me coming back, seeing that particular sight."
When asked what challenges this unique ecosystem faces, Sinclair said they have to do almost entirely with the human population surrounding Serengeti, which has doubled in the last 20 years. "There's the direct impact of illegal hunting," he said. But there's also the indirect impact of development and the effect of tourism in the park, which "creates disturbances in the soil, the vegetation." The animals themselves are affected too, particularly the predators, he pointed out. "If you have 20 vehicles around a cheetah, it basically cannot go and hunt."
Ironically, although tourism is a significant source of income, it doesn't actually benefit the local people. Tanzania has a large number of national parks but only two of them -- Serengeti and Kilimanjaro -- are self-sustaining, Sinclair said. The profits generated by these two go toward funding the other parks, rather than to the local people surrounding the Serengeti.
There's also a looming water crisis. The region's one major river is the Mara, which originates in Kenya and flows through the Serengeti and then to Lake Victoria. "The headwaters of the Mara are in woodland in Kenya, and those forests are being cut down," Sinclair explained. "So the source of the water is drying up." There's also illegal irrigation in Kenya and more and more water is being drawn off before it reaches the Serengeti plain.
"The Mara River is the lifeline for the wildebeest in the dry season. If that dries up, the wildebeest migration will stop," Sinclair said. Lake Victoria is fed by only a few sources of water. If it shrinks, "not only will millions of people will suffer, because they use it for fishing. But it's large enough in area that it creates its own weather systems, and provides the gradient of rainfall." Without Lake Victoria, Sinclair warned, "that gradient of rainfall will disappear and the whole Serengeti system will collapse."