Sydney Reefs are a very special ecosystem.

Sydney has unique marine life which has eveolved in geogrpahic isolation for millions of years.

 

 

 
catfish garden
Schooling Catfish can number into many thousands. When they are fingerlings, they will swirl around obstacles such as a diver like a shawl. They do have spines on the pectoral fins and dorsal fins. In adults, these spines are dangerous and highly toxic. Sponge gardens definitely rival tropical reefs for colour. The Mosaic Sea Star is a spongivore. Big Bellied Sea Horses will reside on some reefs for years. The biggest threats to Sea Horses has been humans stealing them to sell to Aquaria. The Sea Horses will always suffer from this selfish act.
gns wsd

The endangered Grey Nurse shark have a resident colony in Sydney. Most of them seem to be juvenile females. This is an adult female. Sexual segragation in schooling sharks is quite common.

Weedy Sea Dragons have excellent camouflage. In the green Ecklonia kelp, they are virtually invisible from more than one metre away.