Get the facts: Red or green substance appearing in waterways

Council has recently been contacted by residents regarding a red or green substance in local waterways; which is a naturally occurring substance called Trichodesmium.  There has also been some discussion in local media regarding the material, in particular a story that appeared in the Bayside Bulletin recently entitled “Beachgoers warned to avoid toxic algae’’. This story may mislead readers and as such Council would like to clarify the following points about Trichodesmium:

–       In the concentrations seen in local waterways, Trichodesmium is not considered dangerous to people or animals.  It is a naturally occurring algae that occurs in warmer dry weather conditions such as those that have occurred recently.

–       There is absolutely no connection between Trichodesmium and dead or dying birds that have been found along the coast recently.  The death of the birds is a natural occurrence that has been reported several times in the media and is thought to be due to exhaustion and starvation as a result of their 10,000 kilometre non-stop migration from northern Russia.


–       The presence of Trichodesmium also has nothing to do with Redland City’s Health Waterways Report Card.  The outcome of Redland City’s Health Waterways Report Card is due to the presence of nutrients in local waterways from rain events washing soil and other nutrients in the water, not due to the presence of Trichodesmium.

Council has information relating to Trichodesmium blooms on its website. Information is also available from the Department of Natural Resources.