Not only is the lion an iconic symbol to Africa but the following two stories have been published recently to highlight different reasons why the lion is imperative to Africa. As an apex predator the lion is vital to proper ecosystem function; its loss within African terrestrial ecosystems could result in serious and unpredictable repercussions throughout the food chain and ecosystem negatively affecting numerous taxa.
The first story is centred on the increase of zebra populations within Uganda. In the 1960s the population of zebra in the East African country was estimated at 10,000. Their numbers declined to 5,500 in 1982, to 3200 in 1995 and to as low as 2,800 in 2003. Today, according to the Uganda Wildlife Authority (UWA) the population of zebras in Uganda is now estimated at 11,814, triple the numbers that were encountered a decade ago.
Zebra are considered one of the most dominant herbivore species, often out-competing other ruminants due to their greater spatial distribution and foraging tactics. However such biological characteristics make them more vulnerable to predation and it has been suggested zebra populations are mostly limited by predation rather than the availability of food resources. Within an ecosystem the annual off-take of large numbers of zebra by predators such as lions limits population density numbers and therefore allows other less competitive herbivore species to sustain themselves within the vegetative carrying capacity. Whilst a recovery of any species within Africa’s wildlife areas is good news, without population regulation of zebra through predation, species such as the zebra may out-compete other herbivores within a given area leading to inter-specific issues and a reduction in overall biodiversity. Lions in Uganda have been in the news many times over the past few years as numbers have declined sharply, with an estimated 415 left.
The second recent story is from the blog of the Lion Guardian program operating in and around Kenya’s Amboseli National Park where only 60 lions are estimated to remain. There, attacks by hyena are on the increase, and replacing lions as a significant source of conflict with humans and their livestock. According to the article “The Maasai community respect and admire lions because they cannot attack livestock unless they are hungry. And even when they do, they kill only what they can eat. For example in a herd of 100 cows, they only kill one. But hyenas kill any moving livestock even if they can no longer eat, which is why they are so disliked by pastoralists”. The hyena are described as “...on the rampage. Their attacks on livestock, at bomas and in the bush when they get lost, are now stretching communal tolerance towards carnivores. Reports of their attacks are not confined to a particular locality, rather they are widely distributed across the ecosystem.”
One outcome of apex predator removal is the rise of mesopredators – those smaller members of the predator guild that are characterized by living in high densities, and have high rates of recruitment and dispersal. A population explosion of baboons through the removal of lion and leopard in some areas has led to a cascade of events including baboons preying on the young of antelopes, causing significant crop damage, raiding the nests of bird species, and even keeping children out of school to help protect maize fields from ravenous troops of these monkeys. Another aspect of increasing mesopredator populations is economic. Higher populations can cause the same or new conflicts with man and costs of artificially controlling numbers can be high due to the high density in which mesopredators can thrive. It is vital that top-down regulation of prey and the impacts on mesopredator populations is acknowledged and considered within in-situ conservation efforts for apex predators. The loss of the lion within African terrestrial ecosystems could result in serious and unpredictable repercussions throughout the food chain and ecosystem negatively affecting numerous taxa. If you are interested in conservation work with lions, take a look at our website and participate in our "Hands-On Lion Conservation Volunteering" in Livingstone, Antelope Park or Victoria Falls.