Brown Tube Worm
Temperate to Southern zones
The Brown tube worm is a highly
significant and plentiful organism of the rocky
shore filtering thousands of litres of water per day from a confined region. It can be identified by the colony of large diameter brown
tubes that are constructed from sand and shell particles.
Colonies extend from low water spring down a metre or more into the sub littoral. They prefer regularly flushed regions such as the sides of surge channels and gorges. The dense colonies stabilise the environment by cementing boulders and rocks together.
It is a ciliary filter feeder and uses a crown of elaborate tentacles on the head to collect food consisting of plankton and organic matter.
The brown tube worm breathes using the peristomial
tentacles and through spoon shaped gills filled with red bl blood cells, located on the dorsal surface.
Unlike the white tube worm they do not have an operculum therefore are less resistant to dehydration. Despite this they are able to withstand dehydration to a certain extent through use of a pseudoperculum which is projections from their tentacles to close off their tube.
The worms undergo synchronous spawning of eggs and sperm which fertilise externally. When the egg hatches it lives for around 2 months as zooplankton. The plankton then attaches to the substrate and build tubes. Due to variable larval settlement densities and short lifespan of approximately 2 years, colony sizes vary over time.
The colony supports micro-communities which takes
advantage of the living and feeding opportunities. This along with its capacity to stabilise the
surrounding environment through the cementing and
consolidation of boulders and rocks makes it an
ecological synergistic organism.