Southern Africa’s game farms are private reserves that house wildlife such as giraffes, zebras and antelope to be used for restocking national parks, meat production or trophy hunting. But these farms have a problem. Warthogs and porcupines want to move around the reserves too, and they have an annoying habit of making large holes under the boundary fences to burrow their way in and out. For cheetahs, these holes are an ideal way to get inside and prey on the valuable game.
Cheetahs are considered pests in these reserves and, in Namibia, game farmers end up killing more cheetahs than livestock farmers do. These game farms needed to find a way to let the warthogs in while keeping the big predators out.
The solution is simple but unusual – have you ever considered whether your cat flap might be used by other animals besides your feline friend? It turns out “swing gates” (a technical term for a glorified cat flap installed along a fence line) are ideal.
According to research I carried out with colleagues in Namibia, recently published in the African Journal of Ecology, warthogs and porcupines have learned how to use these gates, but big cats such as cheetahs and leopards don’t seem to have figured this out yet. It could be that the big cats see an intact fence and do not bother to investigate the integrity of it, whereas warthogs may be more inquisitive and spend more time rummaging around the fence line looking for holes.
This is great news for both livestock and wildlife farmers because it now stops movement of large carnivores into farms and can limit the amount of expensive antelope or buffalo that are killed by predators. With the threat removed, farmers now do not need to resort to hunting carnivores to limit the damage that they cause on the farms, and it also means that they no longer kill hole-digging species like warthogs, aardvarks and porcupines to limit the number of fence breaches.
Our study determined that the number of holes dug by burrowing animals under game fences decreased over time and this was most evident when the swing gates were easily accessible and ideally placed. This means installing gates in open areas with harder soil, dense vegetation, close to the watering holes where water-loving, perpetually-thirsty warthogs like to hang out.
What’s more, swing gates are far cheaper than electric fencing – the conventional way to stop animals burrowing their way in. So it’s really a win for both people and wildlife. Electric fencing requires continual application of weed killer to stop the grass from short-circuiting the electric current, but the only maintenance that is needed with swing gates is the occasional hole-filling from the rogue warthog that does decide to dig a new hole under the fence.
Temporary fix but no long-term solution
If we want to conserve cheetahs and promote co-existence between humans, wild game and wild predators, then using fences to exclude big cats from their natural habitat won’t work in the long term. But for the time being, this is a quick and simple fix. Farmers can add swing gates to their tool box of effective yet non-lethal techniques to combat predation of livestock.
Laurie Marker, founder of the Cheetah Conservation Fund and one of the study’s co-authors, points out why it is so crucial that this works for game farmers too. Predators, she says, create large financial losses on game farms. “Swing gates will enable us time to work on a permanent solution that will enable all species to peacefully coexist on the same land, such as the development of conservancies”.
In these conservancies wildlife is allowed to roam free, without high game fences. As Marker points out, “neighbouring farmers and land occupiers then manage the resources collectively, allowing for predators to be managed within the larger landscape system.”
In the meantime, you better watch out what other critters enter your house via your cat flap, as it might not just be Felix that is coming inside.