Tracking long-term ecological change in South Africa’s thicket landscapes

At this year’s Thicket Forum, hosted by Nelson Mandela University in June, Rae Attridge from NatCarbon shared insights into a multi-year biodiversity monitoring project designed to evaluate the effectiveness of large-scale restoration in South Africa’s degraded thicket ecosystems.

Restoration in the region has largely focused on planting Portulacaria afra (Spekboom), a species known for its carbon sequestration potential and resilience in arid environments. However, as explained in Rae’s presentation, restoration does not automatically equate to ecological recovery. “We need to understand how species and ecosystems are responding—not just whether plants are growing back, but whether biodiversity is returning in a meaningful way,” she noted during the session. 

To address this, NatCarbon has developed a structured monitoring framework that compares actively restored sites to intact reference thicket. The approach focuses on six taxonomic groups—vegetation, mammals, reptiles, anurans, birds, and bats—using passive and repeatable methods such as vegetation surveys, camera traps, and acoustic monitoring. 

Early results point to a more complex picture than anticipated. Vegetation surveys show that while species richness in restored sites can be similar to that in intact thicket, the composition often differs. Bird communities show higher richness and distinct assemblages in intact areas, indicating a sensitivity to habitat structure and ecological integrity. Mammal diversity appears consistent across both site types, suggesting that generalist species are persisting. Interestingly, reptile richness is higher in degraded areas, likely due to the dominance of disturbance-tolerant species in more open habitats. 

Rae emphasised the importance of monitoring not just for scientific understanding but for improving management. “Having a reliable, scalable monitoring system allows us to track whether restoration efforts are truly supporting biodiversity over time,” she said. 

A key objective of the project is to identify indicators that are both ecologically meaningful and practical—able to be used by trained field staff as well as community members involved in restoration. This ensures that biodiversity monitoring can be embedded in long-term landscape management. 

As restoration initiatives continue to expand across the Eastern Cape, this work provides essential insights into the ecological outcomes of interventions and supports more adaptive, evidence-based decision-making. 

Article by Rae Attridge