|Author(s)||M.T. Mentis & R.R. Duke|
|Journal||South African Journal of Wildlife Research|
Carrying capacities for wild herbivores in a variety of bioclimatic regions in Natal were examined. In calculating stocking rates, estimated relative energy requirements of the various species were used to equate species of differing size. Herbivores were grouped according to the anatomy of their alimentary canals and to the type and parts of plants they prefer to eat. Stocking rates of wild herbivores and of wild domestic herbivores mixed were compared in five different bioclimatic regions to the carrying capacities employed by agriculturalists for domestic cattle. Carrying capacities for wild herbivores on sour and mixed veld, and probably on sweet veld too, do not exceed the capacities for domestic cattle under present circumstances. The reasons for this are believed to concern the impracticability of applying rotational grazing systems for game animals, and the need to balance the proportions of large and small largely grazing species. In many instances, large grazing species are either difficult to acquire for stocking on private land, or cannot be maintained for reason of disease. Multi-species communities appear to hold advantages over single-species communities provided that large species predominate and the other species of different feeding types are chosen carefully. Small ruminants in particular require concentrated food which is scarce on most natural veld, and such animals should not be stocked in excess of 40 50% of the agriculturalists' capacity figures. Since stocking rate and animal performance per animal are inversely related, the concept of carrying capacity is not applicable to land on which herbivores are managed for a sustained yield. Here, an optimal stocking rate, giving maximum economic return on costs, is appropriate. Such optima, which have not been but can be determined, probably are well below the carrying capacity.
Keywords: carrying capacity, Natal, wild herbivores, bioclimatic regions, optimal stocking rate
Authors: M.T. Mentis & R.R. Duke
Journal: South African Journal of Wildlife Research