The map below shows toxic algae blooms warnings and advisories issued by local, state or federal agencies between May 5 and September 16, 2013. Not all states have monitoring and reporting programs, and as a result, the map below does not reflect all states where toxic algae blooms occur. Learn more about discrepancies in monitoring and reporting in our 2013 report and our methodology for tracking toxic algae reports. Mouse over map markers for more information about specific outbreaks.

View a list of all Toxic Algae reports we are tracking Report a Toxic Algae bloom

On September 24th, 2013, Resource Media and the National Wildlife Federation jointly released a report on 2013's summer Toxic Algae blooms. Download the full resolution report PDF

Download a low resolution report PDF