White Lions of the Timbavati
When I was working in South Africa two years ago, I had the chance to meet a very unusual subspecies of big cat. Following up on a lead from one of my Afrikaner coworkers, I managed to get an up-close and personal encounter with the “white lion”, a rare color mutant of the subspecies Panthera leo krugeri which is found only a few wildlife reserves and parks in southern Africa. This lions used to occur naturally throughout the Timbavati region until they were completely extirpated from the wild through selective trophy hunting. There are now estimated to be less than 300 of these individuals world-wide.
At a reserve where a pride of these lions is maintained, I helped a local veterinarian examine one of these magnificent animals who was suffering from a gastrointestinal aliment. As you can see, the lions are not pure white – they are not albino, but rather leucistic, and this coloration is the result of a recessive gene known as the Chincilla or color inhibitor gene. There is a mutation in an enzyme (tyrosinase) that results in decreased melanin production and inhibits its deposition along the hair shaft. Pigmentation is only found in the very tips. “Whiter” lions are the result of less pigment in the hair shaft, and even the manes and tail tips of the males are pale instead of the typical golden or black. They maintain pigment in their eyes, paws, and lips.
Interestingly enough, this pale coloration does not seem to inhibit their fitness in the wild. The White Lion Trust has been reintroducing prides of white lions back into their endemic habitat with much success. The goal of the organization has been to conserve this rare phenotype and increase the biodiversity in the Timbavati region. According to their reports, the white lions do not exhibit decreased hunting success and breed successful, producing several cubs over the last few years. Increasing genetic diversity in dwindling wild populations is important for the preservation of the subspecies as a whole. Good luck to the white lion! It was amazing to have a chance to interact with these magnificent animals.
Snapshot Serengeti 
An interesting topic that brings up the subject of scientific ethics. So much has been written about saving white lions but it should be put in perspective.As you say white lions are not a subspecies and historically, in a small corner of South Africa one or two white lions where born, rarely. Having a whole pride of white lions (re-introduced) is just not something that would naturally have occurred.
It is good to maintain the genetic diversity but at what cost. White lions are an anomaly and should crop up every now and then, in fact as white lions can be born to two tawny parents it is unlikely that hunting has removed the gene from the Timbavati lions and a white cub could be born naturally. If and when this happens it should be celebrated. But what need is there to be breeding them purposefully and releasing them. We risk much with genetic manipulation.
Just like white tigers and black leopards currently zoos around the world are breeding and interbreeding to produce white lions because they are a curiosity and attract more customers. There just shouldn’t be 300 white lions in the world, their occurrence naturally is one or two every few years in one small area, on the greater scale of conservation if none are where ever born again it is not a disaster. The trait Leucism has no inferred advantages and so its loss on the genetic scale is not great. Many birds exhibit leucism and we are not rushing to set up breeding projects for them.Why then do we spend so much time and money in saving the white lion.
I think you raise very many valid issues, and I agree with your over-all bent. As a minor point, from what I understand reading up on the goals of the White Lion Trust, they make a special effort to ensure that the lions they release are not inbred. More importantly, I think by drawing public attention to this ‘special’ subspecies, conservation effort and funding is shunted not just into breeding up the individuals themselves, but I would assume this also goes into protecting their native habitat and natural areas — with cascading effects for all species in their ecosystem. I am not associated with their project, so I can’t say this for sure, but I would assume that effort going towards preserving this species has similar umbrella effects as occur when effort goes into the conservation of any particularly charismatic organism. I think an added layer to this particular case is something that I didn’t mention, which is the important spiritual significance the white lions hold for some of the indigenous peoples. Again, from the research I did to write this post, it seems that this is a major theme for the White Lion Trust.