Lions outright

The big cats recover surprisingly - but only if they are protected behind fences. What should be done to achieve better results?/Jason J. Goldman

The article is published with the approval of Scientific American Israel and the Ort Israel network

In the summer of 2015, one dead lion, Cecil, grabbed the news headlines. Sport hunting does involve such entanglements, but rich hunters armed with big guns are not the biggest problem facing the lions, members of the biological species Panthera leo. According to the definitions, the lions are in danger of extinction. They suffer from the shrinking of their habitats, the dwindling of prey, killing as revenge for taking the lives of people and farm animals if they were really killed or if there was only a suspicion of it, illegal hunting for the needs of traditional medicine, and more. In Africa, these big cats are crowded into an area that is only 17% of their previous habitat, and only one population survives elsewhere in the world, and it is isolated in India. A new study reveals that although the situation of lions in Africa seems dire, there are places where these cats are actually thriving. But these success stories are more complicated than meets the eye, and the future well-being of Africa's lions will not come cheap.

Although the king of beasts has been studied quite a lot, most studies have focused on certain populations and not on the entire species, of which only about 20,000 individuals remain. But combining data from these studies now allows researchers to examine the condition of the carnivore that symbolizes Africa most of all from a continent-wide perspective. In the latest study of its kind, a group of researchers led by Hans Bauer, a zoologist from the University of Oxford, compiled data from surveys conducted in 47 lion populations over the past 20 years. They found that all but one of the nine population groups of lions in West Africa are in significant decline (and two of them may already be extinct). The situation of the lions in East Africa is not benign either. The population in the Serengeti is the only large group in the east of the continent for which the forecasts tend to be positive. According to the analysis, the probability that the lion population in West Africa will decrease by half within 20 years is 67%. whereas the likelihood of this in East Africa is 37%.

Analysis of the data also revealed a glimmer of hope: most lions in South Africa are thriving. In this part of the continent, "it is very likely that lion populations will maintain their size," says Craig Packer, a lion expert at the University of Minnesota who oversaw the study published in December 2015 in the Proceedings of the National Academy of Sciences (PNAS). Why? Because they live in very remote deserts and are difficult to settle and therefore humans do not endanger them, or they are protected in reserves and fenced gardens.
Even small fenced reserves have value in terms of preserving the species, says Peter A. Lindsey, a researcher with the conservation group Panthera who was not involved in the study. "Every area that we manage to make protected can contribute to conservation. That's why everything that adds is fine," he says. Fences allow lions and other animals to survive in small patches of land. Without them, the large mammals would not have been able to exist in these areas without coming into contact with humans, farm animals and agriculture. In many places, conservation organizations can only work to restore animal populations by assuring local communities that these fences will keep them safe.

But not all biologists believe that fences are the solution that will save the lions. Confined lions make only a "limited contribution to ecosystem functioning," Bauer and his colleagues wrote in their study. Doesn't the fencing turn the landscape into an upgraded zoo and the lions into an expensive tourist attraction?

If the fenced area is large enough—South Africa's Kruger Park, which is mostly fenced, is about the size of the state of New Jersey—lions can still fulfill their role as a top predator and regulate the ecosystem because they limit the size of the antelope, buffalo, and ungulate populations. others, and it helps to keep the plants company. But even though humans are the ones who have demarcated the area, "There is no doubt that Kruger Park is a real ecosystem where real ecological processes take place," Packer says.

If the reserves in Africa were as well funded as Yellowstone Park, they could take care of lion populations with an average size of about two-thirds of the maximum size in the same area - a step up compared to the current situation.
But most fenced areas are much smaller. "If you restrict wildlife to small, protected, fenced areas, you have to manage those areas quite intensively, because the population dynamics are a bit wild," says Lindsay. "And the reasons for this are not well understood." The intensive management includes the implantation of hormonal contraceptives in females to prevent population explosion and the trapping and transfer of individuals to other reserves to maintain genetic variation. If a small group of lions is not permanently enriched with new genes, they may suffer from the effects of an excess of lions, and the population may collapse.

This intervention helps, but does not solve everything. "The lion community as a whole has to realistically adapt to our priorities and the priorities of [local] communities," says Andrew Jacobson, a researcher at the British Zoological Institute. A fence will not be useful, for example, in places where it will harm the migration of animals, such as the wildebeest, which migrate across the Serengeti every year following the rains.

And one is whether lion researchers stand on one side of the fence or the other, most agree that the future of Africa's lions depends more on dollars than it does on fences. Many reserves and gardens in Africa are struggling to exist due to a constant lack of budget. According to an analysis done by Packer in 2013, it is cheaper to keep lions in fenced reserves. In a fenced area, maintaining the lions costs about $500 per square kilometer (without the high cost of erecting the fence), and in contrast, in unfenced areas, $2,000 is only enough to maintain a population at half the maximum density it can reach. But an analysis by Scott Creel, a researcher at the University of Montana found that, in a dollar-for-dollar comparison, the investment in unfenced areas helps a greater number of individuals.

Indeed, if the inspectors of the reserves in Africa were as well funded as in the Yellowstone Park in the USA at about 4,100 dollars per square kilometer, they could take care of an unfenced lion population with an average size of about two-thirds of the maximum population size in the same area - a step up compared to the current situation. Despite the money coming from ecotourism and sport hunting being used for lion conservation in general, only a small portion of this revenue usually goes to the reserves.

In places where ecological constraints do not allow effective fencing, the funding is essential in order to provide an economic incentive to local residents that will allow them to bear the costs of living alongside large predators, such as the loss of farm animals to hungry lions or the avoidance of grazing on the reserved lands. Indeed, if the lions' wild prey is crowded out by the grazing herds of the rising African population, the lions will have no choice but to become accustomed to beef. And that, in turn, can lead to more lion killings in revenge. The lions will therefore be trapped in a situation where they directly confront humans on the one hand and suffer from a shortage of food on the other. There are ecosystems that fences will benefit, while others need conflict mitigation projects, but such efforts require a lot of money.

The new insights therefore indicate a way forward: the lions will be able to continue living in Africa as their home even in the long term, provided that the international community agrees to finance it. "If the level of funding for Africa's protected areas can be increased," says Lindsey, "there is no reason why today's protected areas cannot contain many more lions."

Jason J. Goldman is a Los Angeles-based science reporter. He writes on human and animal behavior, wildlife biology, ecology and environmental conservation for Scientific American, the BBC and other magazines. He completed his PhD in the study of avian cognition at the University of Southern California. Edited the book Science Blogging: A Basic Guide (Yale University Press, 2016). He is also an avid fan of raccoons.