Written by Tim Coles
Feature Photo Courtesy of Alex Tozer
In recent years there has been a greater demand for projects in Africa than we could provide. The classic example of this was the 2016 UK university tour where we ran out of South Africa places by the second or third week of the tour! 2017 will see the opening of three new sites in South Africa, each bringing a new perspective to our terrestrial research.
New sites in South Africa
There are three new sites opening in 2017 and all of them are in Big 5 reserves. Dinokeng Reserve is in the high veld just north of Pretoria and is an example of where a local government sees an opportunity to develop an income stream for local communities whilst creating a wildlife corridor and existing property owners gain a benefit from the development. The local government invested in buying the land and fencing the reserve as well as fencing around each of the properties, such that it is now the homeowners who are fenced in and the animals running wild! This has resulted in a huge boost to tourism in the area and property values within the reserve and the reserve is constantly increasing in size as new landowners press to have their land included.
The near-unpronounceable Makgokolo is a game farm next to the Big 5 reserve of Karongwe in the low veld adjacent to Kruger National Park. Accommodation in Makgokolo will be in an up market lodge and there will be regular trips into the Karongwe reserve.
The third new site is the Gondwana reserve on the fynbos in the Western Cape and is an example of where adjacent cattle and game ranchers put together a potential reserve, fenced it and introduced game. Funding comes from setting aside 2 X 50ha areas where individuals can buy a 1ha plot, build a house/lodge for their own use and have traversing rights across the whole reserve.
The overall objective of the Opwall surveys in South Africa, which are run in conjunction with WEI, is to develop a manual of best practices for wildlife conservation reserve managers based on the latest scientific data and the results of some of these research projects across the high veld, low veld and fynbos vegetation communities. Each of the research sites being used by Opwall in 2016 in the high veld (Welgevonden) and the low veld (Balule, Pongola, Thanda) in addition to the new sites to be introduced in 2017 have specific research questions that are being addressed and which will help towards completion of this manual. Examples of the research questions being addressed are:
How do you calculate the carrying capacity for elephants in a reserve?
At the moment reserves are allocated carrying capacities for elephants from a look up table that gives maximum densities for different rainfall levels, but are these correct? The 8000ha Pongola Game Reserve, has a mix of tourism lodge and hunting lodge operators. There has been strong pressure from the hunting lodge operators within the Pongola land owners’ association to reduce the elephant population in order to leave sufficient forage for other browsing species. The current elephant population is around 85 individuals, but the National Elephant Management Association (NEMA) carrying capacity for the reserve has been estimated at 40 animals or less. However, this estimate is based upon a density estimate of 0.35 elephants per km2, which was derived over 30 years ago from a reserve in Tanzania so is unlikely to be transferrable to Pongola.
This high density of elephants has led the landowners to worry that the existing elephants are causing damage to the ecosystem by exceeding their carrying capacity. If this were true you would expect to see the percentage damage to each bush or tree in the study plots to increase and the total woody vegetation to in the reserve to decrease as elephants knocked over more trees. The long term vegetation data sets gathered by Opwall at this reserve are being examined to answer these questions.
How to minimise disturbance to elephants from game viewers?
This project is being run at the Welgevonden reserve in 2016 where the reserve management are keen to understand the relationship between game viewer activity and aggressive behaviours from the elephants. The research aims to assist in developing a new code of conduct for approaching elephants and how to reduce aggressive incidents. The researchers will be based in a vehicle as far as possible from the elephants whilst still being able to view them so that the effect of approaching vehicles on herd behaviour and aggressive responses can be measured.
Measuring population levels of large herbivores and predators
Many of the reserves use helicopter counts of the large mammals at the end of the winter period to provide the necessary data for reserve management decisions, e.g. restocking levels. The counts are done in 200m strips up and down the reserve and to date have provided the only reliable method for estimating populations. However, the Opwall teams at a number of reserves are completing DISTANCE based surveys of the large herbivores with sections of each transect divided into lengths with different total visibility to provide more accurate estimates. The advantage of these studies are that the costs are zero for the reserves (indeed they provide an income for the reserve) and it also enables valuable species such as Nyala to be counted accurately. Counting Nyala from the air leads to a significant underestimate in their numbers since their flight response is to hide under thick vegetation. By comparing the results of DISTANCE analysis to the helicopter counts, we can prove the reliability of the land-based method.
How do you calculate the carrying capacity of reserves for browsing species?
This is one of the most surprising finds to date of the Opwall/WEI research in South Africa. Carrying capacity of an area for browsers is normally assessed from look up tables related to rainfall levels or from measurement of trees and using the BEVCOL programme to estimate the volume of forage from the tree and shrub dimensions input. Both of these methods make significant and often difficult to justify assumptions. In the Thanda, Pongola, Balule, Makgokolo and Dinokeng Reserves it is proposed to actually measure the quantity of forage available within the reserve in a height of up to 2m, during July when leaf biomass should be approaching its’ lowest level. We will do this by collecting all the leaves in this range within sample plots, then calculating the weight and calorific value.If, at this time of year, there is plenty of available forage despite the presence of browsing game, it suggests the carrying capacity has not yet been reached, and so there may be spare capacity for introduction of additional browsers.
What fire management regime is required to maximise the biodiversity of the fynbos and also enable some grazing and browsing capacity?
The Gondwana reserve has a very different vegetation to that of the normal game reserves in high or low veld areas, and lies within the Cape Floral Kingdom which has the most diverse flora of any region in the world. Before the area was settled by man this vegetation community supported Elephant, Rhinos, Lions and Antelope species such as Eland, Blessebok, Bontebok and Springbok. The main natural vegetation communities in this region are Fynbos and Renosterveld. However, these important vegetation communities are under threat from introduced species and human development, leading to some flower species having become extinct.
By creating a protected area that contains these endangered plant communities, Gondwana Reserve provides an opportunity to protect those alongside large game and the Big Five, a major attraction for most visitors! Another attraction is the amazing diversity of fynbos, which is naturally renewed periodically through burning. After a fire the vegetation begins to re-establish but how long does it take for the climax Protea communities to become established? Immediately after a fire, grasses and edible herbs grow within the burned sections and these provide valuable grazing for the large mammals on which the reserve relies for its income. As the Fynbos recovers the percentage of edible grasses and herbs declines to be replaced with non-palatable woody species. So from a conservation viewpoint the argument has always been to maintain long burning cycles whilst from a grazing viewpoint the shorter the burning cycle the better. The management of the reserve is currently using a compromise position of burning on a 10-year rotation. The purpose of the Opwall/WEI research programme is to determine how this burning rotation affects the floristic and faunal diversity of the Fynbos communities and the carrying capacity for the large game species to determine if the 10-year cycle is the best compromise position or whether modifications to the strategy are required.