Environmental Conservation

Papers

Use of local ecological knowledge in the management of algal blooms

THOMAS A. SCHLACHERa1 c1, STEWART LLOYDa1 and AARON WIEGANDa1

a1 Faculty of Science, Health and Education, University of the Sunshine Coast, Maroochydore DC, QLD 4458, Australia

SUMMARY

More frequent and severe algal blooms are symptomatic of increasing ecosystem stress in coastal waters. Economic losses typically follow and local governments are forced to ‘manage’ this issue. Because many blooms are not monitored, local ecological knowledge (LEK) and oral history are the only practical tools to obtain data on bloom characteristics and identify their drivers. LEK was applied to outbreaks of brown algae on popular tourist beaches in south-east Queensland (Australia). Structured interviews with local citizens who had a close and frequent connection with the ocean provided 541 bloom records, which showed that blooms are regional (≥400 km) rather than local, and that they are a historical (≥40 years) rather than a recent phenomenon. LEK frequently cited that particular wind regimes coincided with the arrival of blooms, but this could not be verified by statistical cross-validation with empirical data. Harnessing LEK was valuable in engaging citizens, in generating testable hypotheses about plume causes, in providing a previously unrecognized historical perspective and in identifying the correct spatial scale of the issue. Multi-pronged approaches will be most effective in addressing blooms where local mitigation actions are combined with broader regional coastal environmental conservation efforts.

(Received October 13 2009)

(Accepted February 03 2010)

(Online publication May 14 2010)

Correspondence

c1 Correspondence: Dr Thomas Schlacher Tel +61 7 5430 2847 Fax +61754301276 e-mail: tschlach@usc.edu.au