Centrostephanus rodgersii is ecologically important on southeastern Australian rocky reefs, where its grazing activity results in a mosaic of barrens and macroalgal habitats. The creation, persistence and demise of C. rodgersii barrens is a major ecological dynamic in this region. Affinity for shelter and nocturnal foraging underlie the mechanism of barrens formation by C. rodgersii. Centrostephanus rodgersii has undergone a range extension into Tasmania facilitated by larval transport in the Eastern Australia Current. Investigation of the impacts of this extension has generated major advances in understanding the biology and ecology of C. rodgersii. In Tasmania lobsters and fishes modulate the success of C. rodgersii and creation of barrens habitat. It could be argued that historically, predators in New South Wales played a greater role in regulating sea urchin populations but this hypothesis remains untested.