Chrysophyte (golden algae) nuisance blooms in the GBR region: causes and solutions (C2.12)

Task leader: Dr Britta Schaffelke, CRC Reef and James Cook University.

Task associates:
De Laurence McCook, Great Barrier Reef Marine Park Authority
Mr Phil Laycock, Quicksilver Connections.

Extensive blooms of 'golden noodle' alga Chrysocystis fragilis have been observed over recent years, and in the late 1980s, on the Great Barrier Reef (GBR) from latitude ~16 to 19°S. These blooms appear to be a significant problem on reefs used by tourism operators as pontoon sites. The occurrence of C. fragilis may be a consequence of recent reductions in live coral cover as a result of previous disturbances by crown-of-thorns starfish and/or bleaching. There is some evidence that hard corals overgrown by C. fragilis sustain tissue damage.

C. fragilis has only recently been identified as the bloom-forming species on the Reef, despite anecdotal information of its occurrence for some years. There is very limited information on its biology and distribution on the GBR. C. fragilis may be a recent introduction to the GBR region, or may indicate chronic disturbance of the reefs in the GBR region. Chronic blooms of this species have the potential to impede recovery of disturbed reefs.

The proposed project will explore conditions that trigger and promote the growth of this type of alga, its reproduction and dispersal mechanisms, and its potential impacts on the health and recruitment of hard corals.