GAA Report Identifies Steps for Better Management Of Harmful Algal Blooms

The Global Aquaculture Alliance (GAA) on May 30 published a report detailing the series of massive harmful algal blooms (HABs) that impacted southern Chile in early 2016 and identifying steps that can be taken to enhance algal blooms management, which resulted in extreme losses of farmed and wild finfish as well as widespread paralytic shellfish poisoning (PSP).

The 19-page algal blooms management report concluded that while clearly there is much capacity and experience among those studying and monitoring HABs in Chile, fragmentation in monitoring and outreach is apparent. The result of a year-long collaboration, the report suggested that CORFO and Chile’s minister of the economy establish a committee of scientists and regulators, including international external authorities, to review existing HAB programs and recommend how they may be better coordinated and managed.

Organized by CORFO, a GAA-led team of experts met with Chilean government officials, researchers, salmon and shellfish aquaculture leaders and artisanal fishermen in August 2016 to gain better understanding of the situation. GAA, an international NGO dedicated to responsible aquaculture and the leading standards-setting organization for farmed seafood, previously worked with government and industry in southern Chile to address the infectious salmon anemia (ISA) virus outbreak in salmon beginning in 2007.

Early last year, an unprecedented series of HABs — which coincided with and were aggravated by a strong El Niño event that included higher than normal water temperatures, reduced rainfall and calm winds — hit the coastal waters of southern Chile. Finfish (particularly salmon) and shellfish farmers, artisanal fishermen and other members of the public in the region suffered financially, and social unrest ensued.

The report’s recommendations are intended to enhance the timeliness of HAB detection, forecasting and tracking through the use of new technologies, supplementing the work already being done in Chile. They include enhanced maintenance of buoys that can identify and count algal cells and transmit results via the Internet for near real-time use and satellite-based remote-sensing systems coupled with the application of physical-biological numerical models.

Some types of data are currently very adequately applied, but the algal nutrient measurements needed to understand and model the concentrations, sources and fates of the natural and human-sourced nitrogen, phosphorus and silica found near aquaculture facilities in the Chilean Inland Sea are limited. The algal blooms management recommendations also include further examination of mitigation methods to control HABs near salmon farms including testing of methods that have been successful in other countries.

The report was prepared by Dr. Donald M. Anderson of Woods Hole Oceanographic Institution, a world leader in HAB research, and Dr. Jack Rensel, an aquaculture consultant and scientist. Also contributing were Dr. John Forster, highly experienced aquaculture consultant, and Dr. Steve Hart, GAA’s vice president of education and outreach.