Ninepin Point is located just to the east of Verona Sands, south of Hobart. It has an unusual aquatic environment. Cold, nutrient-rich sea water from the southern ocean is overlaid with tannin-rich freshwater flowing from the Huon River. Tannins are leached from the decaying organic matter in the Huon River catchment. The resulting tea-coloured water reduces the light levels on the reef. This allows the growth of a fascinating array of invertebrates, fish and red seaweeds, normally found only in much deeper water on Tasmania's east coast. Over 100 species of seaweed have been recorded in the Reserve.