Kruger Park’s biological diversity is in serious trouble! Part 2

Elephant Management in Kruger National Park (2)

Today’s blog starts off with the acknowledgement that, in the first blog, we reviewed the history of elephants repopulating Kruger National Park starting in 1905; and that we came to the calculated conclusion that, in 1955, there were approximately 3500 elephants in the park. We also paid some considerable attention to the fact that elephant populations can – given the right circumstances – double their numbers every 10 years. So the species is actually very resilient. Having covered that general background, we can now get back to the main theme of this story – the management of elephants in Kruger National Park.

NB: Kruger National Park is 20 800 square kilometres in extent; or 8000 square miles.

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Elephants do one of two things to their habitats:

(1). When they are maintained in their correct numbers (i.e. when their numbers are constantly within the carrying capacity of their habitats), they utilise the vegetation in a sustainable manner. And THAT means: However much vegetation they eat or destroy during any one year, it is replaced naturally during the next growing season. So, year by year, the state of the habitats remains naturally healthy and dynamically stable. In such an environment, the biological diversity of the national park prospers.

(2). When elephants exist in numbers that exceed the sustainable carrying capacity of their habitat, they utilise the vegetation in an unsustainable fashion. That means nature cannot replace in any one growing season, the vegetation that the elephants ate, or otherwise destroyed, during the previous year. So the habitats constantly degrade every year; biological diversity is adversely affected (species of plants and animals start to become locally extinct); and the game reserve begins an inexorable slide towards becoming a desert.

So when, in 1960, the Kruger scientists voiced their concerns that the park’s elephant population had exceeded the carrying capacity of its habitat, their statement was taken seriously. How did they know this? They knew it because the elephants were measurably starting to irreparably damage the game reserve habitats!

The National Parks Board (as SANParks was known in those days) operated under a long-standing mandate from the South African parliament: which had dictated that, above all else, it was the board’s duty to maintain the national park’s biological diversity.

There was nothing strange in this dictum. In national parks the world over, nothing else is more important than maintaining a national park’s biological diversity.

When the Kruger scientists determined that the elephants in the national park had exceeded the carrying capacity of their habitat, therefore, they recommended that the board should start an annual elephant culling programme. Culling – a management process that, every year, reduces the elephant population by a number equivalent to its annual increment – was the correct and obvious solution to this problem.

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In 1944 Kruger Park scientists – perhaps(?) understanding (even then) that it was necessary to start measuring the habitats of Kruger – carried out a study of top canopy trees over an extended region in the Satara area (which is right in the middle of the national park). And, thereafter, they continually looked towards the results of that study as the benchmark for determining habitat health.

NB: Top canopy trees are the most important element of any and all deciduous woodland and riverine forest habitats in Africa because their high canopies determine what happens to all the many different-level understory plants that grow in their shade. Within this great variety of subordinate habitats, a myriad      different plants and animals occur. This is where the greatest biological diversity in any wildlife sanctuary exists. And it is important to understand that these shade dependent plants can only grow in environments where their special shade requirements are met. When a big trees die, therefore, all the plants that once lived under its canopy die, too; and the animals that were dependent on (and which are specially adapted to) these understory habitats, also disappear.

The 1944 Satara top canopy tree study determined that, on average, there were 13 top canopy trees per hectare in the study area. And as the Satara area was reasonably representative of the conditions that pertained throughout the greater part of Kruger, this figure was arbitrarily accepted as being “the norm” for the park as a whole.

The top canopy woodland habitats at Satara remained unchanged until the late1950s.

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In 1965 an ordinary meeting of the National Parks Board was convened at Kruger’s headquarters, Skukuza, to discuss the elephant status in the park. It was presided over by the then National Parks Board Director, Dr. Rocco Knobel. At that meeting the Kruger scientists told Dr. Knobel that an evaluation of the Satara study area that year revealed that the numbers of top canopy trees had been reduced, since 1955, as a direct result of elephant action, from 13 to nine.

Dr. Knobel asked the scientists what the elephant carrying capacity of Kruger National Park was. None of them knew – but their recorded reduction of the number of trees at Satara was revealing. It told Dr Knobel that the numbers of elephants in the park was definitely too many at that time.

Throughout the 1960s, the National Park’s Board was busy opening up new borehole game water supplies all over the national park. And, because Dr Knobel believed that the extra water would spread the elephant load more evenly during every dry season, he drew that possibility into the equation.

He made a decision. He agreed that an elephant culling programme should be instituted that had the objective of maintaining elephant numbers at their present level – at least until all the planned new waterholes had been created. When the water development programme had been implemented, he instructed, the scientists should then determine just what the elephant carrying capacity for the national park was; and, when that statistic was known, the elephant culling programme would be reviewed.

NB: Concomitant with this instruction, Dr Knobel declared that the buffalo in the park should also be culled with the same objective – to keep their numbers  stable at their then numerical strength.

It took another two years – preparing the ground – for the elephant culling programme to commence. The first cull took place in 1967 when the elephant population was trimmed down to 7000 animals. This was an arbitrary figure that the scientists themselves had decided upon – but it was in line with Dr Knobel’s instructions. It should be noted, however, that this arbitrary figure was not determined by scientific research and/or calculation.

Nevertheless, thereafter, 7000 became their annual culling target. The actual numbers of elephants the scientists took off every year is immaterial; but, if the incremental rate (6.8%) was their guideline, the average annual take off would have been 476.

By the time the 1967 cull took place, however, the Satara top canopy tree count was down to 6 trees per hectare.

Thereafter, the annual cull occurred religiously every year, when +/- 500 elephants were removed from the Kruger population; and the numbers were consistently reduced to 7000 every year. That figure – 7000 – was the one constant in the whole operation.

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I am now impelled to record my assessment of this state of affairs.

If the standing trees at Satara decreased in number from 9 to 6 between 1965 (when the decision to start culling was made) and 1967 (when the first cull took place) surely “someone” should have realised that 7000 elephants – the culling target – was far too high? Nobody apparently did – because it remained at 7000 for the next 27 years.

By 1974 – eight years into the culling programme – the top canopy tree count at Satara had dropped to 3 trees per hectare. Still the culling target remained at 7000. Nobody saw fit to change this number to fit the known circumstances at that time. The culling progressed at the same pace, regardless!

By 1981 – 15 years into the culling programme – the number of top canopy trees at Satara had been reduced to 1.5 trees per hectare. There was still no reaction from the Kruger elephant management team. The culling target remained at 7000.

By 1994, the Kruger Park staff had stopped counting the numbers of trees left standing in the Satara study area – because there were, essentially, none left and it was nonsensical to maintain the charade. Instead they made another assessment. They declared that, by 1994, the numbers of standing trees at Satara “had been reduced by 95 percent”.

Today it is constantly stated that the Kruger Park’s top canopy trees – all over the park, generally – have been reduced by “more than” 95 percent. Their yardstick, of course – as it always has been – was the average healthy and optimum number of top canopy trees that once existed in the Satara study area, in 1944-1955.

Up until 1994, the culling target figure had remained at 7000 animals; and that year, following immense pressure from the animal rights lobby, the culling programme in Kruger National Park came to an end.

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This is, overall, a very sad tale because the greatest components of Kruger National Park’s once enormous biological diversity – c.1955 – was invested in the habitats that once thrived in the canopies of those big trees; in their higher branches; and in the massive shaded and several-layered understory habitats that existed beneath them. Furthermore, under the misguided circumstances prevailing during the culling era, parliament’s mandate to the National Parks Board – to maintain the species diversity of the park – was unattainable; and was seemingly abandoned.

Dr.Knobel’s instruction to the Kruger scientists – to ascertain the national park’s elephant carrying capacity after the game water supply programme was complete – was never carried out!

But the saga doesn’t end here. There is a lot more to come. The story continues in the next blog in this series; and then, to the present time, in many more blogs thereafter.

Ron Thomson. CEO. TRUE GREEN ALLIANCE