Predators, such as barn owls, have long been encouraged in oil palm plantations to control rats, which damage the ripening fruit. Attempts to establish new barn owl populations in the plantations have been very successful, and many estates, including those surrounding the BEFTA plots, now contain high densities of these birds. The owls are monitored regularly and encouraged to breed, through the construction of artificial nest boxes, made out of plastic barrels that are raised seven or eight metres above the ground on the end of a post! Other native predators, such as leopard cats, may also be important in controlling rat populations. A researcher working at the SMARTRI research centre, Aude Verwilghen (CIRAD), is studying just that and was kind enough to take us out on a night drive around the plantation to see these beautiful felines.
Although other species of forest cat disappear when forest is converted to oil palm plantation, leopard cats can survive and proliferate in these disturbed areas. Despite this, as our vehicle pulled out of the research centre gates and headed into a newly replanted area of the estate, I didn’t really expect to see any. From where we were standing in the back of the pickup, flashing the spotlight around, the plantation looked like a wasteland. Even with new planting methods and rapid establishment of a cover crop, replanting can lead to significant erosion. In the newly replanted area we were driving through, portions of the surrounding land had slipped away to expose the sandy soil, which looked almost white in the glare of the spotlight. We didn’t have long to wait; within the first two minutes the ghostly shape of a barn owl took off from a tree stump a few metres ahead of a car and, screeching, glided away. Twenty metres further on, there was another, and then another. The plantation was teaming with them! As we rounded the top of a hill and looked down into the valley, we got our first glimpse of what we were searching for. In the spotlight were two sparkles of gold: the eyeshine of a Leopard Cat. The creature continued to stare as the vehicle approached, and we were able to get a better look at its delicate form and markings. It was about the size of a domestic cat, but of a more slender build. The tips of its ears were rounded and black, while the rest of the body was pale yellow and decorated with dark lines and blotches. After another moment it turned away and disappeared into the vegetation at the side of the road, no doubt to continue its nocturnal hunting. Over the next hour or so, we saw another three of the leopard cats, including a young one, which allowed us to watch it for several minutes. Encouraging native predators like these beautiful cats must represent a valuable opportunity, not only to preserve native carnivores, but also to control rat numbers in the oil palm plantations.