Fire as a Management Tool
The use of fire as a management tool in African savannas has long been a controversial topic. When the Kruger National Park was first established, fire was viewed as a destructive entity and was actively excluded.
Fortunately scientists soon realised that fire was a key determinant of savanna ecosystems by releasing nutrients held in old, dry plant material, by influencing herbivore distributions and feeding patterns, by being necessary for certain seeds to germinate and by influencing the grass/tree balance that defines savanna ecosystems.
However, the original interpretation of this influence resulted in managers applying very rigid and fixed burning regimes, with areas being burnt at the same time of the year at the same return interval. Recent research has shown this to have a very negative influence on biodiversity by favouring those species with a life cycle better adapted to the specific burning regime. Contemporary ecological theory emphasizes the importance of disturbance processes in maintaining the composition and structure of savanna ecosystems by continuously “resetting the clock”, and fire is recognised as the most important disturbance process of all. Central to this is the increasing appreciation of the historical importance that pastoralist fires and ad hoc lightning fires played in the maintenance of savannas.
Although the Waterberg is an area with limited potential for secondary production (i.e. conversion of latent energy in plants into animal body mass) due to nutrient constraints, there are no such limitations for primary production (i.e. conversion of solar energy through photosynthesis into plant matter). As such, there is considerable vegetation growth each year during the wet season, and the resulting fuel loads for fires are therefore very high. Given that the Waterberg is also an area prone to numerous lightning strikes, it is reasonable to assume that, historically, fire was a very important factor in maintaining ecosystem function in the region. Lightning fires spread outward from a single point of ignition and therefore have a very different behaviour to controlled perimeter burns applied by management and evidence suggests that fires with point ignition that occur at differing intervals are far more effective in maintaining habitat diversity across a landscape by preventing bush encroachment and by creating an optimal patch-like mosaic.
As such, Welgevonden has moved away from a fixed management burning regime to a more ad hoc point ignition policy whereby lightning fires are closely monitored but allowed to burn. However, in doing so, fire behavior is less predictable and thus manageable and it is therefore necessary for every lodge on the reserve to have a suitable fire break and to be suitably equipped to prevent and fight fires. However, given the distribution of infrastructure on the reserve and also the fact that the reserve is confined, it is occasionally necessary for management to intervene to prevent fires from burning too large a proportion of the reserve at any one time and/or to assist with preventing damage to infrastructure and/or to prevent fires from spreading onto neighboring properties that do not subscribe to the same fire policy.
