information:classification, structural:reformatting
Tidal rockshelves and rock pools

A series of sandstone rockshelves and rock pools fringe the entire coastline and Port Hacking Estuary Line of the National Park broken on by small sandy beaches and gentle freshwater inlets. Some of the most commonly encountered molluscs in this habitat include black nerites (Nerita atramentosa), turban snails (Turbo undulata), zebra snails (Austrocochlea porcata) as well as the commercially farmed Sydney rock oyster (Saccostrea glomerata). One of the most common and distinctive seaweed species that grow among the rock pools and the nearshore rockshelves is Neptunes necklace (Hormosira banksii) a seaweed made of small buoyant fleshy bead-like structures which resemble strongly that of a necklace. Beds of the primitive sea-squirt cunjevoi (Pyura stolonifera) are common along coastal rockshelves which are covered by high tide and near sea spray. Considered the most beautiful and obvious of the Royal National Parks' sea anemone is the waratah anemone (Actinia tenebrosa) named after the waratah flower due to its corresponding flame red coloration. A common sea-star found growing in the rock pools is the biscuit sea star (Tosia australis).

The fatally toxic blue-lined octopus (Hapalochlaena fasciata), the most common of the blue-ringed octopus species in the area, can, when touched, prove to be fatal within minutes. They are nearly impossible to spot unless pointed out, and can be found in small or large rock pools. The best way to avoid stings completely is to not allow any part of one's body to enter any rock pool.