In our last issue, Ron Thomson gave his opinion on elephant culling, saying it was imperative to cull in order to maintain species diversity. He spoke of his understanding of the new management plan, which divides the park into blocks where elephants are managed differently, using ?Thresholds of Potential Concern?. He said that it was based on sound scientific principles, but said it had many flaws, describing a few as he saw them. He went on to encourage the use of ?biome management.?
Riverine forest habitats comprise largely evergreen trees growing in a narrow strip along a riverbank. The trees obtain their water from the river or from beneath the river sands. Animals that are associated with riverine forests are bushbuck, red duiker, blue duiker and, in some places, red squirrels. It is here, and only here, that you will find Pel?s fishing owls breeding. There are many under-story plants that grow only within the canopy shade of the riverine forest trees, and there is a myriad of birds and insects and reptiles that you will find nowhere else.
Many of the species of understory plants, and most of the smaller animal species, you will find in no other habitat. The combination of the plants and animals that live within a riverine forest represent its biomic qualities. Behind the riverine forest there is often an alluvial flood plain where a deciduous woodland biome occurs. Here the trees obtain their water only from the rain but the rich soils enable very large trees to become established. Mopani woodland is another biome that is easily identifiable, as is teak forest.
Other biomes are called high-veld grasslands, montane forests, montane grasslands, and sand-dune deserts. Reedbeds and marshes are two others. And there are many, many more. Each one has particular attributes, however, and each one has a range of animal species that are especially adapted to it. You don?t find hippo in a sand-dune desert, for example, or grassland larks or cranes living in a forest. Many animal species are very specifically adapted to particular biomes whilst others will roam across several biomes in their daily travels to find food.
When large herbivores ? like elephants ? become too numerous in a game reserve they can easily eliminate entire biomes in a very short space of time. And because elephants are not specifically adapted to the biomes that they destroy, they remain unaffected for very long periods of time. When the new elephant management plan is applied in Kruger, particular sensitive habitats will be destroyed in those management blocks that allow elephant numbers to increase unchecked. And it will be the more sensitive species of plants and animals, those that are the most especially adapted to the habitat conditions that exist within particular biomes, that will be the first to become locally extinct.
They will also be the last to return when the management regime is reversed. Theoretically! The question is - from where will they return? There is a great danger to biodiversity, therefore, in a management regime that purposefully allows large herbivores to increase in number to levels that wipe out the major components of a game reserve?s sensitive biomes. This fact remains valid even if, later, the management strategy is reversed and the vegetation is allowed to return to its former glory ? theoretically.
Far better that Kruger?s wildlife managers start to identify the biomes that exist in the game reserve, to manage them for stability, to maintain their full age spectrum of trees, and to maintain their full spectrum of under-story plants and animals. It follows that ANY animal, in whatever numbers, and of whatever species, that starts to undermine this state of stability should thereafter be removed entirely, or reduced in number, until the state of desired stability returns. This is the only way to be absolutely sure that the species diversity of a national park remains intact.
The management of biomes, with the object of keeping them, individually, in a reasonably high-climax and stable state, supports man?s renewable natural resource priority management obligations, too. This is an hierarchy of priority that starts with the soil. Man?s obligation to protect the integrity of the soil is of paramount importance in his natural resource? management actions. This is because without soil there can be no plants. And without plants there would be no life on planet earth.
Man?s second consideration must be for the appropriate protection of plants because plants not only feed herbivorous animals, they also ? together with local physical environments create the many habitats that are necessary to support the world?s wide animal species spectra. Plants also protect the soil from the erosive actions of (especially) rain, sun and wind. Man?s third (AND LAST ON THE LIST) priority consideration is for the animals. This does not mean animals are of no consequence. They do, after all, appear on man?s list management priorities. What it does mean, and emphases, is that the soil and the plants are greatly more important than the animals.
It also implies that if the soil is intact, and if the plants in the habitats are healthy, the animals will, automatically, be healthy too. Another thing this ?conservation? priority list tells us is that when animal rightists insist that the elephant be our first priority in a game reserve, they are putting the cart before the horse. They are clearly very wrong! It is my contention that the new elephant management plan for Kruger does not pay enough attention to man?s ?conservation? priorities, and that it will place many species of plants and animals at too much risk of local extinction. I believe it would be much better, all round, if wildlife management in Kruger became more biome orientated whereupon, I believe, the park?s biodiversity would be secure.
Ron Thomson worked in the Rhodesian/Zimbabwe National Parks Department for 24 years where he rose to the rank of Provincial Game Warden i/c., Hwange National Park ? Zimbabwe?s premier game reserve. After leaving Zimbabwe in 1983 he worked as Chief Nature Conservation Officer for Ciskei and then, for three years, was the Director of the Bophuthatswana National Parks Board. He is a university-trained ecologist. For twenty years, before retirement, he was a registered Member of the Institute of Biology, London, and a Chartered Biologist for the European Union.
His African big game hunting experience is vast ? by anyone?s standards. Ron has published five books. Their principle purpose is to create a betterinformed public ? better-informed, that is, about wildlife management affairs. The series of articles written by him, which will be appearing in The Kruger Park Times in the months ahead, are all excerpts from his latest book A Game Warden?s Report. He can be contacted at tel./fax. (012) 2530 521; or firstname.lastname@example.org.