Hugo Bezuidenhout

Efficient Evaluation of Biodiversity Concerns in Protected Areas

Monitoring is a vital component of keeping protected areas in desired states. Lack of robust designs, however, impedes efficient monitoring. We ask two questions—how does effort at a specific site as well as number of sites in a plant community influence richness, abundance, and diversity indicators. Large mammal herbivory biodiversity influences are a key concern for managers of Mokala National Park. We anticipated that changes in biodiversity indicators (vegetation, ants, and birds) associate with herbivore intensity of use of landscapes. We identified flat deep sandy plains and undulating shallow rocky hills as focal landscapes. Our focus was on finding optimized effort at survey sites as well as the number of sites. Monitoring to evaluate change in diversity and abundance needs far less effort than evaluating change in richness. Furthermore, given the variance at the landscape level, monitoring of species abundance and diversity allows easier detection with less effort and at shorter intervals between surveys than that required for richness. Even though a mechanisms-based approach directs monitoring, conservationists need to evaluate feasibility. In our case, measurement of richness is unlikely to detect herbivore effects. In general though, we have illustrated that focused monitoring designs can robustly evaluate conservation objectives.