You could call Vincent van der Merwe a cheetah matchmaker.
He maintains a studbook of the big cats, which helps pair together compatible mates. If two cheetahs from an isolated group mate, they may have unhealthy offspring. But if he couples two cheetahs from distant populations, they'll likely produce strong cubs. His mission is to rebuild diverse, genetically healthy populations of the vulnerable animals throughout their African homeland.
For more on big cats, tune in to Big Cat Week, premiering Monday, Feb. 20, at 9/8c on Nat Geo WILD and learn more about the National Geographic Big Cats Initiative, a global initiative that supports scientists and conservationists working to save big cats in the wild.
Van der Merwe, a National Geographic Big Cats Initiative grantee and conservation biologist, knows he has to work fast. In the last hundred years, Africa's human population has increased twentyfold, pushing cheetahs out of 91 percent of their historic range. Today around 7,100 cheetah live in the wild, according to a recent study in the Proceedings of the National Academy of Sciences. That’s down from an estimated 14,000 cheetah in 1975. (Read "Cheetahs Are Dangerously Close to Extinction.")
The big cats once roamed nearly all of Africa and much of Asia, but their population is now confined predominantly to three African countries: Namibia, Botswana, and South Africa. The species is already almost extinct in Asia, with fewer than 50 individuals remaining in one isolated pocket of Iran.
National Geographic caught up with van der Merwe to learn more about his work as a big cat Cupid.
Q. What’s the current state of cheetah conservation in South Africa?
A. South Africa is Africa's most developed country, so it's particularly difficult for cheetah to traverse the landscape and long gone are the wide, open spaces for cheetah to roam freely. All that we are left with are fragments of natural habitat. What we have done with our few remaining wildlife reserves is fenced them, so we have to swap individuals between these reserves to maintain genetic integrity and prevent inbreeding. And South Africa is the only country, worldwide, where we've actually seen an increase in wild cheetah numbers.
One of the biggest and most successful conservation operations in Africa is the nonprofit African Parks Network. They manage 10 large reserves in 7 countries across Africa, and they've essentially created safe space for a myriad of species over six million hectares of land. These are the real heroes of conservation.
What are some of the advantages and disadvantages of the fencing approach?
The disadvantage is that you're limiting gene flow, so there is potential for inbreeding. The advantages are that you limit human movement into reserves, you cut down poaching, you cut down snaring, and effectively create safe space for cheetahs. Fencing plays the crucial role of creating safe space for wildlife. This approach is undoubtedly working, and our numbers in South Africa are up to about 1,200 cheetah, the third largest population worldwide. (See more big cat pictures.)
How do you match up potential cheetah mates?
I manage a studbook for  cheetah in 53 different reserves across the country as part of the Endangered Wildlife Trust's Carnivore Conservation Programme. I effectively identify which cheetah are related to each other, and we prevent putting those cheetah onto the same reserves. It's "human-mediated gene flow," which sounds very sexy, but it's actually just a case of conservationists loading cheetah onto their vehicle and driving them to a new reserve. [haha nice]
What are some of the risks that the cheetahs face during the immobilization and transportation process?
It's an incredibly stressful experience for these wide ranging animals to be put into these small, confined spaces for up to a 20-hour drive.
We've also learned that cheetah that come from reserves that don't have lion—we call these "lion-naïve” cheetah—do not perform very well when you move them onto reserves with lion. Cheetah need to be lion-savvy, they also need to be leopard and hyena-savvy. You cannot take a cheetah from a predator-free environment and try and put them into a fenced area with a high density of predators. (Also see "Cheetah Breaks Speed Record—Beats Usain Bolt by Seconds.")
Also, cheetah need a short period of time to acclimatize to their new environment. When we bring cheetah to new reserves, we put them into an enclosure called a boma for six weeks to three months. It allows the cheetah to realize what other large predators are present and most importantly, it kills their homing instinct. As with any cat species, they have an instinct to go back to where they originally came from.
What happens after they're released from the boma and onto the reserve?
The favorite part of my job is definitely, without a doubt, getting to that stage where you open up the boma gate and let that animal go … and do what cheetah normally do. That's an incredibly rewarding and enriching experience. (Read how bomas protect livestock in Tanzania.)
As a scientist you need to be objective, but is there any sort of personal connection?
When you actively work with these animals there is no doubt that you develop an emotional connection. The very best moment is when you get that phone call from the reserve manger saying, 'Vincent, we've got four new cubs that were born to the cheetah that you brought in here six months ago.'
That is what really brings joy to my heart.