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Cyanobacterial harmful algal blooms (cyanoHABs)

CyanoHABs are a large growth of cyanobacteria (not algae) that can produce toxins harmful to humans and animals.

The increasing prevalence of cyanobacterial harmful algal blooms (cyanoHABs) and the toxins they produce are a global water-quality issue that threatens human and wildlife health and necessitates additional monitoring of recreational and drinking water source waters.

Multiple strategies to address cyanoHABs are ongoing and include reducing nutrient sources, monitoring and predicting concentrations of toxins, minimizing exposures to humans and animals, and treating waters to reduce or eliminate cyanoHAB toxins once they occur.

In Lake Erie and inland lakes in Ohio, elevated microcystin concentrations have caused water-resource managers to issue recreational water-quality advisories, and detections of microcystin in source waters have caused drinking-water plant managers to increase monitoring and adjust treatment methods (Ohio Environmental Protection Agency, 2015). Contact – Erin Stelzer (

HABs in lake.

Early warning system to estimate toxic cyanobacteria bloom accumulation in US Lakes and Reservoirs

The USGS began a sampling and monitoring effort at Caesar Creek Lake and Clarence J. Brown Reservoir (Buck Creek Lake), Ohio as part of the Cyanobacteria Assessment Network (CyAN).

The CyAN ( is a multi-agency project between EPA, NASA, NOAA, and USGS to develop an early warning system using satellite data to detect cyanoHABs in freshwater systems. Microcystins and other cyanotoxins, however, are not pigments and cannot be directly detected by remote sensing.

In situ hydrologic, water-quality, biologic, and meteorologic data are collected during satellite overflights at inland lakes. Data will be incorporated into site-specific statistical models and used in the development of a nationwide tool to detect cyanoHABs, which will help anticipate and respond to cyanoHAB-related water emergencies.

This study advances the understanding of toxic cyanoHABs in lakes and reservoirs, the processes that determine cyanoHAB formation, helps predict changes caused by cyanoHABs regarding the quantity and quality of water resources, and delivers timely hydrologic data, analyses, and water-resource decision-support tools.  Contact – Jessica Cicale (

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