Skip to content

Harmful Algal Blooms threaten human and ecosystem health, and disrupt aquaculture and wild fisheries, tourism, and other resources in marine and freshwater systems.

What are Harmful Algal Blooms (HABs)?

Marine and fresh waters teem with life, much of it microscopic and most of it beneficial and harmless. There are, however, some species of algae and cyanobacteria that cause harm, either through the production of potent toxins or through the accumulated biomass during their “blooms”. Impacts include human and wildlife illness and mortality, ecosystem disruption, and economic losses to coastal communities.

HAB Species

Learn about different toxic or harmful algal species, and the poisoning syndromes they cause


See where harmful algae are distributed in the U.S. and around the world


Discover how harmful algal blooms impact human health and coastal economies, wildlife, ecosystems, and more


Learn about the national and international research programs focused on understanding, managing, and preventing harmful algal blooms


Major programmatic and informational resources regarding harmful algal blooms, as well as fact sheets and hotlines


Programs and activities focused on prediction, control, mitigation, and HAB event response

News and Announcements

Be SMAAT! Join the Social Media Action Alert Team!

May 12, 2020

Are you active on social media? Do you want to engage your networks to help with HAB-related legislative action items? If so, contact Holly Bowers to be added to the team ( A few times per year members are provided with ready-to-post messaging and hashtags to share on Facebook, Twitter, Instagram and LinkedIn. Your small…

Read More

Survey on HARRNESS Update

March 29, 2020

HARRNESS was a decadal plan (2005-2015) designed to facilitate coordination of national HAB-related activities among research and management communities by highlighting and justifying needs and priorities, and suggesting strategies or approaches to address them. This report has surpassed its intended lifespan, and an update is sorely needed to continue to serve as a guide for…

Read More

New article collection for the Algal Research Community: Algal Research and Harmful Algae Partner with Data in Brief

March 26, 2020

Data in Brief is partnering with Algal Research and Harmful Algae to publish an ongoing article collection of data announcements called  “Algal Announcements,” which will include: (1) announcements of harmful algal blooms, and (2) announcements of new algal strains; objective is to provide freely available info benefiting researchers, policymakers, entrepreneurs, water managers, engineers, etc. Additional…

Read More

Additional article categories in Harmful Algae

March 26, 2020

The journal Harmful Algae has recently expanded the types of articles it is soliciting to include several short communication categories: Policy Analysis; Mini-Reviews; Perspectives (for detailed descriptions, see link here), in addition to original research articles, review papers, and book reviews.

Read More

Northeast Algal Symposium 2020

March 6, 2020

The 59th Annual Northeast Algal Symposium has been postponed until 2021.  This conference will now be held April 9-11, 2021 in Burlington, Vermont. Please visit the Northeast Algal Society’s website for more information:

Read More

IFHAB Workshop

February 3, 2020

In response to the COVID-19 pandemic, this year’s workshop has been cancelled, and will be rescheduled for 2021.  Additional information will be posted as it becomes available.

Read More

2020 Course on Identification of US HABs

January 16, 2020

The Provasoli-Guillard National Center for Marine Algae and Microbiota (NCMA) is planning to offer the  5th U.S. training course on the identification of harmful algae in the U.S. marine waters.  The course will be held from August 19-29, 2020 (travel days should be August 18 and August 30) at the Bigelow Laboratory for Ocean Sciences…

Read More

Guardian article about HABs

January 15, 2020

A recent article published in the Guardian provides an overview of HABs and their expansion, with an emphasis on the role of climate in driving their increased frequency and toxicity. The full article can be accessed by clicking HERE.

Read More

IOC International (‘brush up’) Training Course on Identification of Harmful Marine Microalgae and Workshop on bHAB species

December 17, 2019

In response to the COVID-19 pandemic, the IOC International (‘brush up’) Training Course on Identification of Harmful Marine Microalgae and Workshop on bHAB species has been postponed.  New dates will be announced a soon as possible.  Additional information can be found here:

Read More

IOC Training Course and Certification on Identification of Harmful Marine Microalgae

December 17, 2019

IOC Training Course and Identification Qualification in Harmful Marine Microalgae 2020 17 May – 15 August 2020 Copenhagen, Denmark. All information, including a course flyer, can be found following the UNESCO/IOC link: The Course is open for applications until 1 April 2020.

Read More