“Monitoring how an ecosystem changes over time is a tricky business and determining how much change you can allow in a system is even more difficult” explains Dr Rina Grant, Sanparks systems ecologist based in Skukuza.

Scientists and managers in the Kruger National Park (KNP) are striving to use an adaptive management system, which allows for some changes in the ecosystem but uses detailed monitoring programmes to detect these potential changes and guide management decisions.

This type of management ap- proach allows for a more proactive stance to ecosystem issues, by predicting certain changes in a sys- tem rather than waiting for change events to occur.

Scientists in KNP, in collaboration with various local and international institutions, have developed a system of Thresholds of Potential Concern or TPC’s. These TPC’s are a set of operational goals that together define the patchiness of ecosystem’s conditions over space and time in the KNP.

TPC's are set for a number of fac- tors that play a role in the ecosystem including fire, water, alien plants and vegetation. Research has shown that the more "patchy" or "diverse" an area is, the more it is likely to be resilient to withstand changes.

These TPC's will address losses in this patchiness of an ecosystem. They are also designed to be an early warning system to prevent detrimental changes to the system, which could result in the loss of biodiversity such as the threat of an increase in alien species or the loss of tall trees in the veld.

“We have a mandate to conserve biodiversity in all our national parks and we are developing these TPC’s for all Sanparks”, says Dr Rina Grant.

Rina and Dr Harry Biggs, also from scientific services in Skukuza, joined Angela Gaylard, the regional ecologist for the frontier region, to discuss the thresholds of concerns for Mountain Zebra National Park, Camdeboo National Park and Addo National Park near Port Elizabeth.

They also met with Professor Graham Kerley from the Nelson Mandela Metropolitan University (NMMU) in Port Elizabeth, to discuss how studies that have been done in Addo can contribute to the setting of thresholds and approaches to monitoring.

The group was also joined by Dr Dave Balfour, the head of scientific services for the Eastern Cape Nature Conservation division to look at monitoring options and to see the effects of previous land uses in conservation areas.

"We appreciate help and input from outside institutions such as NMMU as they have extensive experience with the veld and animals in the Addo region as a result of the research they conduct here, and can help guide our decisions and set up practical and feasible monitoring programmes" says Rina.

With suitable monitoring programmes in place to see how the vegetation and animal numbers change over time, both scientists and managers will be better informed to make meaningful and appropriate management decisions in future.

By Dr Rina Grant and Michele Hofmeyr