In August this year, artist Peter Hall was enjoying an early morning game drive through the mopane-peppered grasslands that dominate the central regions of South Africa’s Kruger National Park when something caught his eye. Creeping through the beige-washed veld was a cat with pitch-black fur. Not much larger than an average housecat but with a lankier build, the animal’s jet-black colour was unlike that of any cat species known to roam the Kruger wilds. Hall quickly snapped a few photos for evidence.

An oddly coloured cat strolling through a grassland in the Kruger Park. Image © Peter Hall

Confident that the animal he’d photographed was an African wild cat (Felis lybica), but unsure of why it was sporting such a sooty coat, Hall uploaded the images to the SANParks – Kruger National Park Facebook group in the hopes of gleaning some insights. While many commenters were quick to dish out admiration for the striking feline (“Absolutely beautiful!”, “Remarkable!) others were more hesitant, drawing attention to the fact that its unique colouration could be the result of crossbreeding with domestic cats.

African wild cats are small adaptable carnivores that range across much of Africa aside from lowland tropical rainforests and true desert habitats. Similar to domestic cats, they come in a variety of shades, from pale sandy-brown in drier areas to dark grey in moister regions. Their long legs are usually decorated with bold black stripes, while the backs of their ears are washed in a russet-brown (a feature only seen in genetically pure African wild cats).

A typically coloured African wild cat. Image © Leonemanuel

Hall’s all-black feline falls outside of the textbook definition for the species. This leaves two explanations: it’s either carrying a genetic condition called melanism which results in an overproduction of the pigment responsible for dark-coloured skin and hair, or it’s a hybrid feline descended from a non-pure genetic lineage. Experts are leaning towards the latter.

“As far as I know, melanism has never been recorded in the African wild cat,” Dr Luke Hunter, Executive Director of the Big Cats Program at the Wildlife Conservation Society, told us via email. “It’s been documented in 14 cat species (of 40 wild species) but it’s actually very unusual in the wildcat lineage, genus Felis; of the 6 wild species in the genus, it’s only known from the jungle cat.”

Hunter points out that domestic housecats – which may or may not be the same species as African wild cats depending on who you ask – followed a distinct genetic pathway that gave rise to black coats. This genetic journey is not replicated by any wild cat species suggesting that the “mutation that gave rise to melanism in housecats probably arose recently, since (or during) domestication.”

The wild cat turned for a moment to glance back at Hall who quickly fired off this shot. Image © Peter Hall

“It seems more likely this is a hybrid,” says Hunter. This doesn’t necessarily mean that the shadowy feline is the offspring of a wild cat and a domestic housecat, but rather that the black mutation made its way into the Kruger population via a domestic cat at some point in time. “It could have happened generations ago,” Hunter explains. “The same process accounts for a high frequency of black fur in North American wolves which traces to interbreeding with early domesticated dogs (which had the mutation) 10,000-15,000 years ago. Black fur is rare in wolves outside N. America where this, presumably, didn’t happen.”

Of course, this is educated speculation. Unravelling the origin story of the mystery cat requires genetic analysis – an exceedingly difficult task that would involve tracking down a lone cat in a reserve the size of Israel. Although anecdotal records of free-ranging, black wild cats have emerged from other parts of Africa, without genetic testing it’s impossible to determine if melanism exists in the species.

Spotted in the Kruger Park last year, this photo of a black cat further supports the existence of either melanistic or hybrid cats living in the area. Image © Röper Botes Photography

“It is possible that the mutation arose independently in the wild cat population,“ Hunter explained. “Melanism has arisen at least four independent times in the cat family (that is, via different genetic mutations).” That’s “surprisingly often” according to Hunter and suggests that it’s possible for the mutation to occur in African wild cats as well.

Dr Marna Herbst – an ecologist who has carried out extensive fieldwork on African wild cats – is skeptical of the melanism theory. There is a “very high likelihood that it is a hybrid cat or feral,” she told us, adding that it’s concerning to discover that these non-wild cats are creeping into the Kruger gene pool.

Findings from a 2014 study co-authored by Herbst found low levels of hybridisation in African wild cat populations in South Africa, especially those cats living in formally protected areas. However, the Kruger National Park – a vast strip of protected land visited by almost two million tourists each year and bordered on all sides by human development – remains a concern for the conservation of African wild cats. “We need to control feral cats around protected areas,” Herbst stresses “Currently AWCs [African wild cats] in isolated areas are still testing genetically pure and that is great. The pressure around Kruger is high and more and more feral cats are spotted in Kruger meaning the risk of hybridisation is increasing.”

Another shot of the elusive black cat spotted by Hall. Image © Peter Hall

John Adamson has been a field guide in South Africa’s flagship reserve since 2005 and has come across at least two cats in the park that were clearly feral or domesticated; one, a mostly white creature resembling a housecat, and the other wearing grey and black stripes untypical of pure African wild cats. Two sightings in 15 years hardly seems cause for concern, but cats are elusive by nature and it’s possible there are many more domestic or feral felines concealed in the 20,000-square-kilometre reserve. The extent of the infiltration, however, is nearly impossible to gauge.

“There is certainly some genetic dilution going on,” Adamson tells us. “You may see an AWC that looks a bit ‘off’ - but how can you differentiate a strange-looking individual from a cat whose great, great granddad was a domestic [animal]?” The African wild cats’ similarity in appearance to housecats certainly makes the task of pinpointing any genetic intruders a difficult one, which is why it’s critical to manage feral cat populations before they become a bigger problem.

The Greater Kruger Alley Cat initiative is trying to do just that. The volunteer program uses food-baited traps to catch, sterilise, vaccinate, treat and re-release feral cats living on the western fringes of South Africa’s most famous game reserve. They hope to reduce cross-breeding with African wild cats and black-footed cats while also minimising the risk of disease transmission.

For Herbst, catch-and-release programs, while helpful, are not comprehensive enough to be effective. “You will always have some kittens somewhere,” she says. “Also, feral cats form social colonies, thus you have an area with a lot of feral cats and the impact of their roaming and feeding behaviour is huge on local indigenous fauna (birds, rodents, insects, amphibians, reptiles).”

The challenge of protecting wild species that roam in the shadow of human development is a particularly difficult one with no simple, all-encompassing solutions. In the best case scenario, the cat would indeed be melanistic, darkened by a genetic abnormality rather than tainted by crossbreeding. Hall remains optimistic: “I personally think it could very well be one and I’ve spent a lot of time photographing African wild cats so who knows?"

Let's hope for the sake of the wild cats, that is the case.

Editor's Note: In a previous version of this article, incidents of African wild cats breeding with domestic felines was erroneously described as "inbreeding". This has been changed to "crossbreeding" for accuracy.