The ‘elephant problem’ debate tracks this logic: dead or damaged trees with signs of elephants being involved equals evidence of too many elephants which requires their numbers to be reduced. This intuitive response may feel right but it is poor ecology. A recent opinion piece in Daily Maverick by botanistEugene Mollbemoans the “loss” of mature marula trees in the Kruger National Park and points a finger at elephants as the cause.
It’s a powerful image: huge grey beasts pushing over large trees, stripping their bark, breaking their branches and causing their die-off. For many readers the conclusion is clear: there are too many elephants and what is needed is for elephant numbers to be reduced. It’s a widely held view (seeCarnie,Pinnock) – it is also deeply misleading.
The real conservation question is not whether Kruger has “too many elephants”, but whether the processes that shape its savannas are functioning. Ecological systems are complex and when we reduce them to simple stories, we lose important insights and risk making poor decisions. Full disclosure: in the 1980s, one of us (Dave Balfour) studied under Moll, whose teaching contributed to a lifelong love of trees, savannas and the exploration of ideas, which is the point of this piece.
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Moll’s piece invites a response as it plays into a common narrative and reinforces what is known as “the elephant problem” – an oversimplified view that links the death of large trees with elephant numbers in Kruger and other protected areas. Contemporary savanna science and management allows us to craft a more nuanced view that embraces ecological complexity and leads to different conclusions. Much public debate about the elephant problem tracks the following logic: we see dead or damaged trees with signs of elephants being involved – bark stripped, branches broken or a trunk that has been pushed over – and we interpret this as evidence of too many elephants.
We then conclude that their numbers need to be reduced. What matters most for trees is not the number of elephants in an area, but what they are doing, and this depends on which animals are present (bulls or breeding herds), how long they are in the area and what else they are eating. Why do we say this?
Two recent scientific reviews (hereandhere) found weak links between elephant density (numbers) and negative consequences for biodiversity. This is not to say that elephants do not change their environment, and this can be locally dramatic, but when one assesses the overall effects, they are mostly limited and can be positive or negative. The impact of elephants on trees varies considerably depending on the context.
There are no predictable or consistent outcomes, and more elephants does not automatically mean more damage to trees. The reason is that elephant behaviour varies between bulls and breeding herds and is highly selective and patchy in nature. Elephant behaviour changes with season, rainfall and the availability of grass and water.
Not all trees are equally favoured. A single bull that lingers at a marula tree can have considerably more impact than a passing breeding herd. Elephants are mixed feeders, switching their feeding between trees and grass.
When grass quality is good and widely available, it is often more digestible thanwoody materialand elephants preferentially eat grass. This means that the relative abundance of grass and trees, which is influenced by rainfall, soils and fire as well as the presence of other herbivores, is also part of the story. Reducing this complex ecological world into a simple numbers game – that is, there are too many elephants – channels our thinking into a world of “stocking rates” and “carrying capacity”, ideas that are more suited to optimising production in an agricultural context than managing the dynamic complex world of ecology and biodiversity.
At best, setting targets and managing towards a desired number of elephants for a park with the size and spatial complexity of Kruger is effectively a scientifically cloaked thumb-suck. It feels like sensible management, but it is false comfort, and certainly not sound ecological insight. So, does this mean we should not manage protected areas?
Clearly not. The first step in managing is to set goals; once we have these clearly stated we can make choices about appropriate interventions. Earlier generations of managers commonly sought to manage towards a certain aesthetic – predictable scenery with open grasslands here, thickets there, big trees lining river banks.
Their primary tools were structured burning plans, fencing, large mammal population control through culling and the provision of artificial waterpoints in dry areas. Parks were treated like large game farms. Increasingly, as our understanding of the role of nature and ecosystems in human wellbeingdevelops, conservation objectives have shifted towards biodiversity more broadly and towards keeping ecosystems as intact and functional as possible.
Doing so requires accepting complexity and change as part of the deal. It means recognising that elephants are not just “tree killers”, they are also important ecosystem engineers. For example, elephants open up thickets and create habitat mosaics that other species respond to; they constantly maintain and change savanna structure and influence ecological processes.
Using these more contemporary ideas, the questions that managers ask will change. Rather than asking “what is the right number of elephants?” we should be asking “where are elephant impacts on important species becoming detrimental and why?” Where elephant impact becomes a concern, we need to ask what the driving dynamics are and use the answer to devise a management response. This approach is very different to simply deciding that an area has too many elephants and seeking to reduce the numbers.
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