May the lions roar again in Akagera

The Lions should be re-introduced in the Akagera National Park as planned sometime next year. Not just for the pleasure of the tourists – more of whom Rwanda could certainly do with – but for a wider and enchanting ecological premise the world is just beginning to re-awaken in the potential of the not-so-alien idea of the trophic cascade. A trophic cascade describes an ecological process that begins with an organism at the top of a food chain that lends beneficial effects to all organisms below it, including the surrounding environment. Bringing back the lions to Akagera, last seen in the park around the year 2000 (reason of which I’ll revisit shortly), would restore them at the top of the food chain. The excitement building among some of those anticipating the re-introduction of the King of Jungle in the park owes it, to a large extent, to various examples around the world. Among them is what happened to Yellowstone National Park in the U.S. after re-introduction of wolves almost 70 years after the last one had disappeared. When the wolves were re-introduced in the park in 1995 the numbers of deer had so built up that, despite efforts to control them, it had resulted in overgrazing and drastic reduction of much of the vegetation. The wolves, few in number, were ecosystem engineers and had a remarkable and far reaching effect. First, they hunted down some of the deer, which soon changed their behaviour and started avoiding parts of the park – the valleys, the gorges – where they could be tracked most easily. Immediately those places started to regenerate. “In some parts,” as narrated in a video easily found on YouTube, “the size of the trees quintupled in just six years. Barren valley-sides quickly became forests of aspens, willows and cottonwood.” By this, the wolves also changed the behaviour of the rivers. The rivers began to meander less. There was less erosion, the river channels narrowed and ponds formed, as the trees bound the soil preventing collapse of the banks. The overall effect is that it created a niche for other species. With the trees, the birds started moving in their variety and numbers. Beavers built dams in the rivers providing habitats for otters, ducks, fish, reptiles and amphibians. You see it unfold in the video: “The wolves killed coyotes and, as a result of that, the number of rabbits and mice began to rise, which meant more hawks, more weasels, more foxes, more badges. Ravens and bald eagles came down and started to feed on the carrion that wolves had left.” It is not hard to picture similar trophic cascade in our neck of the woods. The African savanna that characterises the Akagera National Park has its unique features and potential for regeneration of its particular flora and fauna with the re-introduction of the lions. The absence of lions must have had some impact. Already an incident or two have previously been reported where buffalos, antelopes, zebras and the like encroaching on human settlements bordering the park; which, perhaps, is symptomatic of the environmental state of the park if the wildlife has to look for food in the farms. However, the Rwanda Environment Management Authority (REMA) is satisfied the ecological situation is not that drastic, though it needs keeping close watch. As to why there are no longer lions in the park – estimated at over 300 before 1994 – they were decimated by poachers and, not to a small measure, by human-wildlife conflict that ensued when the returnees made their triumphant way back home with their thousands of cattle after the liberation struggle. That, however, is history. Rema has assessed that the lions will easily adapt to the local habitat. Their re-introduction will be a boon to the Akagera Park ecosystem, and most certainly to the local tourism industry. The writer is a commentator on local and regional issues

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May the lions roar again in Akagera