Centrostephanus rodgersii is a native sea urchin species in New South Wales, Australia, with a diet primarily consisting of macroalgae such as kelp. Urchin barrens are underwater habitats dominated by sea urchins and are characterised by little to no macroalgae cover. Barrens are a source of ongoing debate in NSW: some stakeholders, including many Traditional Owners, view them as ecosystems depleted of biodiversity and indicative of mismanagement. In contrast, recent research suggests that certain species depend on barrens, and they are increasingly recognised as representative habitats of NSW rocky reefs.
This study centers the perspectives of Traditional Owners through yarning circles, highlighting concerns about overfishing and the decline of culturally significant species. Ecological surveys using drones and underwater cameras assess kelp and barren habitats. Early results show similar overall fish abundance, but clear differences in species composition.
Aerial surveys indicate multispectral imagery can detect macroalgae under favourable conditions, while LiDAR is less effective. New “blue boat” technology is being trialled to improve mapping. Braiding Western scientific approaches and Traditional Knowledge has proven effective in generating new insights into urchin barren dynamics in NSW by extending the period of available information and integrating diverse knowledge systems.