Update (20150805): From yesterday’s, no, the day before yesterday’s Ace, comes this bit:
Without hunting lions have no economic value for the local people or ranchers. In fact they’re a giant menacing pain in the ass since they tend to eat the locals’ cattle as well as occasionally the locals themselves. There’s really no upside at all to having an apex predator like a lion prowling around your village or ranch; only bad things can happen. Yes, there are photo-safaris but unless you’re near tourist areas and are set up for it, there’s not much money in this. So the reality is that without any economic incentive to keep the lions around, the locals end up driving them out or just poisoning them.
And here to paraphrase Jack Dunphy the alternative to allowing hunting is not perfection – it’s the alternative. With no hunting at all you won’t get a Lion King-Simba happy existence on the savannah, instead you’ll see a slow gradual extinction of lions as a species due to loss of habitat and eradication by humans. Lions will not die out from hunting – rather it will be because none of the locals want them around or care enough about their continued existence to protect them. Ultimately the lions will live or die by whether the local people allow lions to coexist with them.
But with controlled trophy hunting, the lions suddenly do have economic value. Because the hunting is so strictly limited hunters will pay a lot to be allowed to take a trophy – $30,000 and up. And $30,000 goes a long way in Africa. This money is split between the land owner, the local villagers, and the government. For the land owner and villagers this makes up on any losses they might have suffered from the lions, and it also means that they have a strong incentive to protect and maintain the local lions e.g. maintaining water pools, not putting up fences, watching for poachers, etc. The money from hunting is a major source of revenue for some remote villages. The revenue to the government helps pay for full-time rangers, park wardens and equipment to protect the lion populations.