southern fan worm
Southern Fan Worms (Sabellastarte australiensis) are a type of feather duster worm characterised by their protruding gills that fan out from their tube dwelling. These invertebrate worms can be found in almost all marine environments including those found along the Great Southern Reef.
Home builder
As a form of protection from predators and rough environmental conditions, these worms build a tube made of mucous around their bodies on which they can put sand and pieces of shell from the seabed that acts as a strong shield.
Feathery gills
Their most distinguishing feature are their colourful feathery gills known as radioles that when clustered together form a branchial crown. The radioles form two fans that project outside of their tube to filter nutrients from the water column and to breathe.
Hide and seek
In addition to their fans, they have additional bristles and hooks that allow them to move freely within their tube, but also on the sea floor in case they need to leave their homemade dwelling behind. These hairs move collaboratively pulling down allowing the worm to quickly respond and withdraw inside their tube if a fish or other potential threat approaches.
Successful spreaders
Most fan worms will reach sexual maturity around 70 mm in body length. The spawning season has been observed to potentially take place year round, which allows for a fast growing population of the species.
Know the locals
In some areas of the Great Southern Reef, invasive European fan worms have spread rapidly colonising infrastructure and reefs. They can be distinguished from the native southern fan worm by its thinner tube, elevated spiral tentacle crown and its habit of growing in groups.
Image: European Fan Worm
Fast Facts:
Species: Sabellastarte australiensis
Family: Sabellidae
Order: Sabellida
Feeding: Detritus, plankton, organic matter
Habitat: Many marine environments including shallow reefs, intertidal zones and deep ocean
Distribution: Endemic to the GSR
Special Power: Home builder which doubles as a protective shield
