Distinguishing features
A small fish with a laterally compressed body that is grey on the front 2/3 and white on the rear 1/3. Maximum size about 14cm. Usually seen in small loose schools near heads of live coral or other underwater structures.
Locations
Common at all island locations with coral reefs or rocky shores. Can also be seen inside the Nelly Bay Harbour development.
Habitat Preferences
Reef crests and slopes, as well as boulder shorelines, jetties.
Biology & Ecology
The Spiny Chromis is very unusual in that it does not have a pelagic dispersive larval phase. Rather, the newly hatched larvae remain in a tight school close to the nest site and are guarded by the parents for several weeks, and then they gradually disperse over the local reef once they reach a large juvenile size. This has implications for the genetic mixing of the stock, however this species is extremely widespread and common across the GBR from the inshore fringing reefs right out to the Coral Sea atolls. The species is also unusual in its diet, feeding both on plankton and algae. The algae may be drifting in the water, but the fish is also a very efficient stealer of algae from the farms of Pomacentrus wardiand Stegastes apicalis.