Evaluating ecological monitoring systems on Mabula Game Reserve, Limpopo, South Africa

Abstract

Ecological monitoring is an integral part of the ecological active adaptive management of wildlife reserves. The present study was conducted as an initial trial of a holistic ecological monitoring programme for Mabula Game Reserve using three existing survey methods. The information gained after each monitoring period and relevant management decisions are: <ul> <li> Large herbivore monitoring: This monitoring system gave specific information on which vegetation community each of the types of large herbivores are utilising and selecting. This information was used in conjunction with the two vegetation monitoring systems and the wildlife count data to determine the stocking rate for each large herbivores on the reserve. If required, the populations can be increase or decreased, which was found to be necessary for browsers on Mabula Game Reserve.</li> <li> Herbaceous monitoring: This monitoring system provides information on the economic and ecological grazing capacity of the individual vegetation communities in terms of Grazing Units. The herbivore monitoring provides an estimation of the actual Grazing Units occurring in a vegetation community. The total stocking rate should be less than the economic grazing capacity (70% of the ecological grazing capacity).</li> <li> Woody monitoring: This monitoring system provides information on the economic and ecological browsing capacity of the individual vegetation communities in terms of Browser Units. The herbivore monitoring provides an estimation of the stocking rate of browsers occurring in a vegetation community, which should be less than the economic grazing capacity (70% of the cological grazing capacity).</li> </ul> The combination of all the results from the three survey methods provided information on the stocking rates for the different types of herbivores, which will ensure optimal wildlife production without diminishing the condition of the vegetation on the reserve. Long-term monitoring will enable the establishment of a large database which can be used to assess the ecological dynamics of the components covered in the holistic monitoring system over time. Changes in habitat selection of the large herbivore can be observed and patterns can be determined in relation to environmental variables such as rainfall. The long-term monitoring of the vegetations layers will provide information on changes in the plant species composition and the structure of the vegetation communities. This information can then be compared to the habitat selection of the large herbivore species and other environmental influence to gain information to help in the determining the cause of any observed changes. Copyright