Long-term cyclic growth of organics across a rock art panel within Nursery Swamp II, a granodiorite rock shelter in Namadgi National Park, ACT, was investigated by NOHC and a specialist conservator, Bruce Ford, using periodic data logging from a range of light, air movement, temperature and humidity sensors. It was concluded that the growth of ‘dust lichen’ across the panel was related to the incidence of wildfire and its removal of adjacent shading vegetation, together with zones of direct UV (sunlight) exposure across the backwall.
The study provided the basis for managing the site’s surrounding vegetation. Removal of accumulated organic material from the back wall using a specialist dry-brushing technique revealed previously unknown Aboriginal motifs.
Detailed and nuanced technical condition monitoring is increasingly important in assessing the resilience of rock art in the face of impacts from our rapidly changing climate.
