Responses of problematic cyanobacteria to exposures of copper containing algaecides

Cyanobacteria (blue-green algae) are associated with production of potent hepatotoxins (Microcystis; microcystin) and dense surface and benthic mats (Lyngbya), which impede critical water resource usages. Water resource managers are in need of effective and efficient treatment techniques for these problematic algae in field situations. Applications of algaecides are considered in situations where algal problems become acute or when critical water usages are threatened. However, laboratory data are needed that accurately predict responses of algae prior to field-scale algaecide applications. Site water and algae were used in laboratory algal toxicity experiments to predict responses of the target alga following an algaecide exposure and to develop a site-specific treatment strategy. Laboratory results were used to guide field-scale applications of specific algaecides in specific water resources. With strategic monitoring programs and efficient use of effective algaecides, problems caused by cyanobacteria can be managed and critical water resource usages can be restored and maintained.