Harmful Algal Blooms(HABs)

What are Harmful Algal Blooms?

A proliferation of unicellular phytoplankton, which can cause massive fish or shellfish kills, contaminates seafood with toxins and alters aquatic ecosystems in ways that humans perceive as being harmful. There are two phenomena, so-called Red Tide and Toxin-Producing plankton.

  • Red Tide: Water discoloration by vastly increased unicellular phytoplankton that induces deterioration of aquatic ecosystems and occasional fishery damage.
  • Toxin-Producing plankton: Phytoplankton species that produce toxins inside of their cells and contaminate fish and shellfish throughout the food chain.

Working Group 3 (WG3) has been established mainly to implement monitoring and assessment of harmful algal blooms (HABs). WG3 has produced following useful outputs for understanding of the situation in the NOWPAP region and providing information to stakeholders.

Activities of WG3


  1. National Reports / Integrated Report on HAB (2005)

    WG3 summarized the information on HAB occurrence in the NOWPAP member states and published the National Reports and the Integrated Report on HABs to understand the HABs situations. In the Integrated Report, various kinds of HAB-related information in each member state were summarized and necessary future activities in this region were clarified.

  2. Integrated Report on HAB (2011)

    WG3 updated the Integrated Report (2005) by adding latest information on occurrences in the member states. In addition, warning and action standards for each causative species in the member states were reported.

  3. Booklet of Countermeasures against HABs in the NOWPAP Region (2007)

    In some member states, HAB occurred every year and damaged fishery activities. To reduce the damage, institutes and experts developed countermeasures against HAB. This booklet introduces information on countermeasures implemented in the NOWPAP member states.

  4. Cochlodinium Pamphlet (2007)

    Cochlodinium polykrikoides is one red tides species which result in large mortality rates in fishery resources and huge economic loss to fisheries. In order to disseminate information on Cochlodinium polykrikoides widely, WG3 developed Cochlodinium pamphlets in English and the languages of each NOWPAP member state.

    Databases and websites

  5. HAB Reference Database (2004)

    To provide reference information on specific studies on HABs.

    HAB Reference Database
  6. Coclodinium Home Page (2005)

    To disseminate information on Cochlodinium polykrikoides. Information is available in each NOWPAP member state's language.

    Cochlodinium Homepage
  7. HAB Integrated Website (2010)

    To share the achievements of WG3 and data in the NOWPAP member states.

    HAB Integrated Website
  8. International collaboration

    While strengthening cooperation and collaboration with NOWPAP partner organizations such as the North Pacific Marine Science Organization (PICES) and IOC Sub-Commission for the Western Pacific (WESTPAC) by participating in meetings, CEARAC joined one PICES activity: development of a PICES scientific report on Economic Impacts of Harmful Algal Blooms on Fisheries and Aquaculture (2014).