|A range of mammals caracal may feed on|
red rock rabbit
Cape grey mongoose
The trouble is that small stock such as sheep and goats are easy prey for these cats and are therefore frequently taken as a substitute for natural prey. The problem is compounded when their natural prey populations have been reduced by injudicious hunting with dogs.
Considering the sheep farmer with numerous resident caracal, it is easy to understand why the caracal are viewed as vermin. It is a problem that cannot be ignored.
The drier areas of southern Africa are best suited to small-stock farming, and the economy of the entire Karoo region is largely dependant on sheep and goats. Young livestock, and young game such as springbok are easily preyed on. When predators prey on the young, there is no increase in stock numbers, an unhealthy situation for a commercial farmer.
Paul and David Collett, both scientists and farmers in the Karoo are tackling the problem head on, in an environmentally friendly way. Paul Collett says they may have come up with a natural solution, simply by controlling caracal numbers.
Many methods have been used to control damage to small stock by the caracal and the oldest of these is the metal trap. It is effective in the hands of a qualified trapper, but it is not selective, also trapping a large percentage of non-target animals such as small antelope, game birds and innocent small predators. Poison as a control would only exacerbate other environmental problems. The use of a well trained and controlled pack of hounds has proved highly successful but only subject to certain criteria being met.
The most satisfactory method it seems is the baited cage trap, but choosing the right bait can be tricky. Using live bait (such as a small rabbit) may work but then it is difficult caring for a caged animal at vast distances. Simply using meat is also pointless as it deteriorates too quickly out in the open. Going a bit more hi-tech using commercial pheromones is also problematic as they are difficult to collect and very expensive to manufacture.
There is however an alternative. Caracals are territorial. Observing the size of territories occupied in the Mountain Zebra national Park, scientists have shown that males dominate larger areas (up to 30 square kilometres) than females (up to 6 square kilometres), moving an average distance of approximately two kilometres per night, whereas females move only one kilometre. And while they roam, they mark their territory by urinating on scent posts around the perimeter. Any new felid approaching the territory sniffs at these scent posts to establish the boundaries of the territory and the identity of the resident cat. Paul Collett investigated whether caracal urine could be used to lure others to a cage trap.
Caged caracal provide a ready source of this scent. While in captivity, caracal urinate repeatedly in certain spots in the cage. Once these are established, Angora goat skins with two months hair growth are placed in the chosen areas, developing a characteristic odour containing pheromones. A piece of this skin is placed in the back of each cage trap as bait, the theory being that other caracal which come to investigate the "scent post", would enter the cage trap, treading on the pedal which causes the door of the cage to close.
His proposed solution worked. A total of 32 caracal in an 8500 hectare area over one calendar year were trapped in these baited cages.
After studying the effectiveness of different types of urine bait (male only, female only and male and female), his research showed that the most effective was the combination of male and female scent from urine. Furthermore, his studies also showed that the cooler months were a more effective time for capturing caracal. He reasons that the scented goatskin may lose its effectiveness during warmer periods as the odours dissipate more easily. The cooler periods may however simply just coincide with young weaned caracal beginning to roam freely as they try to establish their own territories.
According to the Colletts who now employ this method on their sheep farm in the Karoo, the method is a success. By trapping caracal, they are able to move them to areas with low caracal numbers, or where caracal are not problem animals; game farms springing up in the area providing the most likely new homes. They have observed that when caracal numbers in their region are moderate, that there is an increase in natural prey animals such as hares, steenbok and dassies. Caracal then tend to leave adult livestock untouched, preferring their natural prey instead. Lambs and goat kids however remain too much of a temptation for the caracal. By lambing and kidding in protected areas, and using the cage trap method, losses of livestock can be almost entirely eliminated.
Working with their neighbours, the Colletts are now active in controlling caracal numbers in their region. They keep male and female pairs in cages, long enough to produce enough scented goatskins for further control of caracal numbers. And occasionally the pair produce more than just scented goatskins. They give birth to one or two kittens at a time. And as attitudes begin to change towards these magnificent creatures, farmers are occasionally opening their homes to a new domestic cat.
Copyright 2002, Science in Africa, Science magazine for Africa CC. All Rights Reserved