The residents of Eden awoke to a sea of pink yesterday morning as an extensive algal bloom had painted the waters of Twofold Bay.

Algal blooms are a natural phenomenon caused by the mass reproduction of tiny microscopic phytoplankton including dinoflagellates, diatoms and algae. They often occur in Autumn and Spring when water temperatures are higher and ocean current movements are greater. 

Some species that cause algal blooms can produce toxins and be harmful to fish, birds, shellfish and even humans. But not all algal blooms are harmful, in fact, many are beneficial as the tiny plants provide a food source for many organisms.

These phenomena are often referred to as ‘red tides’ but scientists argue that this is an incorrect description as they are often not red and are not related to tidal movements.

Interestingly, some species of phytoplankton are bioluminescent, that is, they can produce and emit light. This can be seen best at night as these organisms essentially ‘glow in the dark’.

It is unclear what species caused the Eden algal bloom, but samples have been collected by SCMDC and sent to CSIRO Marine and Atmospheric Research in Tasmania for analysis.