Abstract:
The Brackenridgea Nature Reserve is a 110 ha protected area established by the provincial
Limpopo Department of Economic Development, Environment and Tourism as a way
of protecting the population of Brackenridgea zanguebarica, a species classified as critically
endangered in South Africa. In the whole of South Africa, the species is found in only one
small area around Thengwe–Mafukani in Venda. It is threatened with extirpation due to high
demand for its medicinal bark. This study investigated the adequacy of the reserve to conserve
the species using a method established in 2001 by Burgman et al. This method involves
12 steps to quantify the risk of the decline or possible extinction of the species and takes
current human activities, disturbances and the viability of the population into consideration
for setting a conservation target. From the results, it was clear that more area is needed for
the current population to survive beyond 50 years. Assuming the status quo, it will require
410 ha to maintain the population, whereas a 50% reduction in human-related activities, such
as cultivation, harvesting and livestock grazing, will lower the required potential habitat to
203 ha and a conservation option, which allows for bark harvesting, will require 179 ha.
Conservation implications: The results of this study will have conservation implication on
management of viable species population within a nature reserve. It will require managers to
take into consideration the reserve size in relation to potential habitats for the development of
species under their management.
