Blue-green algae : present and future

On a yearly basis since September 1989, the residents of Rockhampton have known of blue-green algal blooms in the Fitzroy River Barrage. These have ranged from small populations of species causing taste and odour problems, to toxic blooms which have posed a serious risk to human health. Blooms have also been detected at Rannes, Moura Weir and Theresa Creek Dam. As many local forms of blue-green algae do not form the surface scums characteristic of southern material, the extent of the problem is not readily comprehended. This paper will cover some of the cyanobacteria (bluegreen algae) which are known to be present in the Fitzroy River catchment, the problems we face with turbid waters and nutrient levels higher than those of the Central and Northwestern Rivers of New South Wales, and a climate and riverine chemistry which predispose this region to cyanobacterial doninance and bloom formation. The future benefits of flow releases will be considered along with potential problems.