03 October 2023

By: Fredalette Uys

Farmers have cause for concern with the new problem of warthogs preying on sheep.

Niël Viljoen, a predator specialist in the livestock industry, says the seriousness of the problem of warthogs transforming from scavengers to predators should not go unnoticed.

This comes after Jan-Hendrik Kleyn from the Mooifontein farm between Colesberg and Hanover observed once again that warthogs were eating his newborn lambs.

Viljoen says if the alternative food source is helping the survival of the warthogs, it will become a priority.

“Livestock farmers certainly have cause for concern. The biggest problem is that the warthogs that catch live livestock transmit this method of obtaining food, the physical hunting and killing of livestock, to the new generation.

“If all warthogs are born instinctively with predator characteristics, the jackal will be a ‘lamb’ for livestock farmers.”

Viljoen says the shift and generalisation of their new food source, the transformation from scavenger to predator, and the adaptability of warthogs are definitely worrying.

Catching livestock

It has been known for some time that warthogs, like bush pigs, catch livestock, according to Viljoen. It was previously believed that the pigs only scavenged on dead sheep, but it has been known for years that warthogs also catch livestock.

Viljoen says warthogs are naturally plant-eaters but they are classified as omnivores, which significantly expands their diet. Plant material is usually the main source of their diet and scavenging on dead carcasses is almost an exception.

“The state of ecosystems and rainfall has a determining influence on their diet. Droughts have a big impact on all life, including warthogs,” he says.

“When natural food becomes scarce, the animals will seek alternatives. The connection between scavenging on a sheep carcass and catching a live sheep has already been made. In other words, the transformation from scavenger to predator has occurred.”

Viljoen says the transformation process must be stopped as soon as possible by the controlled removal of warthogs that habitually hunt livestock.

However, farmers operate on their own, and they will be able to make a difference only with joint, well-managed and coordinated management of the problem, he says.“If the transformation process is stopped as soon as possible, it will not only benefit livestock farmers but it will also certainly ensure the survival of the species (Phacochoerus africanus).”