Global Harmful Algal Blooms


PROJECT TITLE: Training programs on Prevention, Control, and Mitigation of Harmful Algal Blooms (PCM-HABs) for mariculture stakeholders of Southeast Asian countries

Scope: Global with Southeast Asia regional focus

Type: seminar and training courses

Timeframe: 2 weeks in summer of 2024, TBD

Venue: Nanning, Guangxi Province, China

Principal Investigators:

Dr Zhiming Yu

Address: Nanhai Rd 7, Qingdao, 266071, China

Tel/Fax: +86-532-8289-8581

E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Contact person:

Dr. Isaac Y. Yuan, This email address is being protected from spambots. You need JavaScript enabled to view it.


Introduction to the program

Training programs on PCM-HABs are attempted to fill the gap between HAB-influenced stakeholders and applicable technologies on PCMHAB. As the initial stage, this program will focus on mariculture stakeholders from Southeast (SE) Asia. Major activities will include training workshops, field demonstrations, and seminars, covering the latest developments in HAB research, spanning from rapid-test kits, toxin detection, early warning, and emergency HAB control. Potential trainees are Early Career Ocean Professionals (ECOP) and mariculture stakeholders from SE Asian countries (Malaysia, Singapore, Thailand, Brunei, Vietnam, Indonesia, and the Philippines), with 2-3 individuals for each nation. In the meantime, the trainees are supposed to be fluent in English communication and with a minimum of five years of professional experience. Moreover, partners rather than SE Asian countries are highly welcomed to join the seminars highlighting HAB status and its impact on mariculture of this region.



Harmful algal blooms (HABs) are a typical ecological disaster that cause damage to the ecosystem structure and threaten human health globally. The increasing events of HABs, particularly along the coast of Southeast Asian countries, become one of the major threats to mariculture industries. For instance, a recent bloom of Cochlodinium sp. in 2020 caused massive mortality of cultured groupers along the Penang coast, Malaysia (Mohd Razali et al., 2020); Karenia blooms in Singapore waters were spotted more frequently in recent years (unpublished data, Leong et al., 2016), and HAB-induced fish mortality was recorded in Thailand (Fu et al., 2021). To combat the disaster, efforts have been put into the Prevention, Control, and Mitigation of HABs (PCMHAB). Various technologies and approaches in PCMHAB have been developed and implemented, for example, rapid species detection methods utilizing genetic chips, Environmental Sample Processor (ESP), and Imaging FlowCytobot (IFCB). Likewise, clay disposal has been introduced and proven to be a promising technology suppressing HABs (Shirota, 1989; Yu et al., 1994; Kim, 2006; Park et al., 2013; Yu et al., 2017) and has been widely used in China and Korea for decades. However, there has not been a specific training course program connecting the needs and aids yet. The gap between the stakeholders who are willing to find some way to mitigate HAB influences, and the latest technologies regarding PCMHAB research is still huge and, thus needs to be elevated and further promoted by extensive collaborations.



  • Roziawati bt. Mohd Razali, 2020, Laporan analisa sampel air di kawasan sangkar ternakan ikan di Bukit Tambun & Sg. Udang.
  • Leong S., 2016, Harmful Algal Blooms in Singapore Coastal Waters: Country Report.
  • Fu Z., Piumsomboon A., Punnarak P., et al., 2021. Diversity and distribution of harmful microalgae in the Gulf of Thailand assessed by DNA metabarcoding. Harmful Algae, 106: 102063.
  • Shirota A., 1989. Red tide problem and countermeasures (2). Int J Aquat Fish Technol, 1:195–223.
  • Yu Z., Zou J. 1994. Application of clays to removal of red tide organisms. I. Coagulation of red tide organisms with clay. J. Oceanol. Limnol., 12 (3), 193-200.
  • Kim h., 2006. Mitigation and controls of HABs. In Granéli E, Turner JT (eds) Ecology of harmful algae. Ecological studies, vol 189. Springer-Verlag, Berlin, pp 327–338.
  • Park T., Lim W., Park Y., et al. 2013. Economic impact, management and mitigation of red tides in Korea. Harmful Algae, 30S:S131–S143.
  • Yu Z., Song X., Cao X., et al., 2017. Mitigation of harmful algal blooms using modified clays: Theory, mechanisms, and applications. Harmful Algae, 69: 48-64.

PROJECT TITLE: Fostering transformative HAB sciences for societal applications

Type: The UN Ocean Decade Kick-off Conference for the Western Pacific and its Adjacent areas

Timeframe: November 25-26, 2021; Session 12, 1030-1230 (UTC+7, Bangkok time)

Principal Investigator name, title: Kazumi Wakita, PhD;  Po Teen Lim, PhD

Address: School of Marine Science and Technoloogy, Tokai University, Japan

                 Institute of Ocean and Earth Sciences, University of Malaya, Malaysia

E-mail: K. Wakita: This email address is being protected from spambots. You need JavaScript enabled to view it.,

             PT Lim: This email address is being protected from spambots. You need JavaScript enabled to view it.

Home page URL:

Other key persons: Mitsunori Iwataki (Asian Research Center for and Environmental Science, The University of Tokyo), Aletta Yñiguez (Marine Science Institute, University of Philippines)

HABs are natural phenomena with increasing frequency and occurrences in the WESTPAC region. Holistic understanding and measures based on multidisciplinary and even transdisciplinary approaches are important to address problems caused by HABs. Based on this understanding, the WESTPAC-HAB aims at promoting transdisciplinary HAB sciences under the UN Ocean Decade. Based on the strong natural science on HABs accumulated through long-time WESTPAC-HAB programme, transformative science would be promoted through effort of engaging various stakeholders to better address various problems caused by HABs. From the natural science side, understanding the biology and ecology of phytoplankton and identification of causative species including morphology among others is the basis for us to adequately address the occurrences of HABs to choose necessary measures for mitigation. To early detect and issue warning to the society, novel techniques such as meta-barcoding and DNA-based analysis are expected to be utilized. From the social science side, understanding social and economic impact by HABs to the society is the basis to adequately address problems. To develop and maintain monitoring system to be effective, analysis of social system including administrative structure and relationships among stakeholders, i.e., national and local governments as management and monitoring bodies, fisheries including aquaculture industries as producers of shellfish and fish, and citizens as consumers are necessary. Thus, engagement of wider stakeholders besides researchers are inevitable.

With the above backgrounds, this Decade Action Incubator “Fostering transformative HAB sciences for societal applications” was a first step for the WESTPAC-HAB to start to generate transformative HAB science. It covered cross-cutting issues of HABs and was the venue to discuss scopes and priorities of Decade Actions including possible resources in the WESTPAC region. Presentations from 5 speakers of the session was summarized as below:

Dr. Mitsunori Iwataki (University of Tokyo, Japan) presented about recent advances in HABs taxonomy and the causative species in the WESTPAC region. He also emphasized the importance in understanding HABs distribution in developing lists of local HAB species. Dr. Kieng Soon Hii (University of Malaya, Malaysia) shared a presentation on harmful microalgae monitoring assessments using metabarcoding approach. He also pointed out necessity of metabarcoding to identify risk and hotspot of HABs, to understand climate change impact ecosystem health and food resources in coastal waters. Dr. Kazumi Wakita (Tokai University, Japan) presented on socio-economic impacts of HABs and sustainability of coastal communities. She introduced an example of adaptation to paralytic shellfish toxin by fisheries cooperatives who operate recreational clam picking parks as a successful initiative to make the traditional marine recreation continue. She emphasized importance of accumulation of good practices to learn from each other which could be tailored to respective social, economic, and cultural conditions of various localities. Dr. Aletta Yñiguez (University of the Philippines) introduced development of an informatics systems serving as a hub for environmental, biological and model-derived information related to HAB and general water quality called HABHub ( She pointed out the need to strengthen real-time ocean observation, to analyze historical data in different sites to further clarify patters, thresholds and forecast model development, and to strengthen engagements and capacities of stakeholders. Dr. Rencheng Yu (Institute of Oceanology, Chinese Academy of Sciences, China) presented on HAB studies for seafood safety and sustainable aquaculture in China. His presentation focused on 1) understanding on phycotoxins and toxic algal, 2) application of molecular and metagenomic approach, 3) threats of macroalgal blooms, 4) large–scale red tides in the East China Sea. He strengthened importance of promoting study on monitoring, prediction and prevention of HABs based on rich understanding on phenomena, taxonomy, biology, and mechanism of HABs. Dr. Tae Gyu Park (National Institute of Fisheries Science (NIFS), Republic of Korea) presented on HAB monitoring program in RO Korea. He emphasized the strength of the monitoring system as being able to provide the red tide news in shorter time during daytime, with the automated field data collection and submission through online portal by local governments.

Group photos of all presenters and speaker of session Harmful Algal Blooms during the conference

                    Group photos of all presenters and speaker of session Harmful Algal Blooms during the conference


HAB research priorities, challenges and future works were discussed and the key points of discussion during the session was summarized as below:

1.continue with the effort in capacity building in HAB sciences through various training workshops and promoting more involvement of social scientists

2.promote application of advanced techniques in HABs monitoring and early warning system;

3.promote sharing of good practices of HAB monitoring, mitigation and adaptation;

4.encourage the application of mitigation measures to minimize impact especially to mariculture industries with due consideration on its social acceptance;

5.strengthen coordination with other national and regional HABs program and IPHAB in development of UN Decade actions on HAB.



PROJECT TITLE: Addressing industry and global insurance needs: impacts of HABs on fish farms

Type: ICHA19, International Meeting Special Session

Timeframe: ICHA19 meeting, October 10-14, 2021; session on Oct 12, 14:00-16:00 La Paz time

Principal Investigator name, title: Vera Trainer, Keith Davidson

Address: NOAA, SAMS

E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Home page URL: (if applicable)

Other key persons (name, title and institution): Mark Wells (School of Marine Science, University of Maine, Orono, ME 04469, USA) and Charles Trick (Department of Biology, The University of Saskatchewan, Saskatoon, SK Canada)

Objectives: A new compendium of case studies on the economic impacts of Harmful Algal Blooms (HABs) on wild and recreational fisheries and aquaculture has recently been published by the North Pacific Marine Science Organization (PICES). Based on a co-sponsored PICES and IOC-SCOR GlobalHAB Workshop on Evaluating, Reducing and Mitigating the Cost of Harmful Algal Blooms, this report compiles case studies on the economic impacts of HABs on farmed salmon and other fisheries, with the aim to guide future research and management decisions as to mitigate the risks associated with these natural events.

The report shows that HAB-related losses faced by insurers of aquaculture operations make up to 45% of insurance claims – and they are larger than any storm that insurers have ever faced.

Despite the several research initiatives of the last two decades, the lack of data, appropriate and standardized protocols, and the dearth of peer-reviewed studies hamper efforts to quantify the societal costs of HAB events, which are increasingly frequent, intense, and long-lasting. As of today, most countries have neither conducted economic analyses of HABs nor collected data that can be used to generate reliable quantitative estimates of net economic losses and impacts. As a consequence, it is hard to develop effective strategies to prevent, control and mitigate HAB events.

In this ICHA2021 side session we will be led in a discussion by insurance industry and on-the-ground aquaculture industry representatives to discuss future research directions and how to work together to address:

- impacts of HABs on aquaculture

- risk thresholds

- early warning

- mitigation cost benefits



PROJECT TITLE: Workshop-based scoping study for developing an early warning system for Harmful Algal Blooms (HABs) in the Arabian Gulf

Scope: Global with Middle East regional focus

Type: Capacity development and networking

Timeframe: 22 and 23 February 2022

Principal Investigators:

Dr Ross Brown

Address: University of Exeter, Biosciences, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK.

Tel: +44 7587702353

E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Dr Qusiae Karam 

Address: Crises Management & Decision Support Program, Kuwait Institute for Scientific Research, PO Box 24885, Safat, 13109, Kuwait.

Tel: +965 24989000 ext. 9107/ 9081

Email: This email address is being protected from spambots. You need JavaScript enabled to view it.


Introduction to the workshop

A virtual workshop is planned for February 22-23 2022 (12:00-15:00 UK time) to explore existing knowledge and data on Harmful Algal Blooms (HAB) and impacts on fisheries and finfish aquaculture in the Arabian Gulf. The workshop is being sponsored by the UK and Kuwait Governments and is endorsed by GlobalHAB. The theme of first day is understanding the susceptibility of the Arabian Gulf and adjoining sea areas to harmful algal blooms (HABs) and impacts on fish health and food safety, and the second day would focus on developing early warning systems (EWS) for HABs for mitigating impacts on fisheries and aquaculture.

 Background Information 

Global aquaculture production from finfish, shellfish and seaweed is projected to grow by 32% from 2018-2030, helping to ensure food security and alleviate pressures on wild stocks from overharvesting and climate change. In the Arabian Gulf finfish aquaculture alone is projected to grow by over 7% between 2018 and 20241. However, the growth of the aquaculture industry is threatened by HABs, which are being observed increasingly at aquaculture sites around the globe, with some HAB species causing mass fish mortalities. Numerous mass fish kills have been recorded in the Arabian Gulf and Sea of Oman and many of these coincide with blooms of ichthyotoxic HAB species and/or high biomass blooms that subsequently decay and cause oxygen depletion in the water column2-4. As an example, in the figure above, chlorophyll concentrations captured by the MODIS Aqua sensor (NASA) represent a bloom of the harmful alga Margalefidinium (Cochlodinium) spp. (in Anderson et al., 2017; Courtesy of R. Kudela and NASA).  


1) Berdikeeva S. (2019). The Rise of Fish Farming in Over-Fished Gulf Nations. Inside Arabia 27 October 2019.

2) Al-Alawi A (2018). Harmful Algal Blooms in Oman. Meeting of the Regional Task Force on Eutrophication and HABs Muscat, Sultanate of Oman, 16-18 January 2018. ROPME/WG-176/4/

3) Al-Yamani FY, Polikarpov I, Saburova M (2020): Marine life mortalities and Harmful Algal Blooms in the Northern Arabian Gulf, Aquatic Ecosystem Health & Management.

4) Attaran-Fariman G (2018). HABs and Phytoplankton Cysts in the ROPME Sea Area. Meeting of the Regional Task Force on Eutrophication and HABs Muscat, Sultanate of Oman, 16-18 January 2018. ROPME/WG-176/4/


Arabian Gulf Harmful Algal Blooms Workshop - programme

DAY 1 (22 February, 12:00-15:00 UK time)
Understanding the susceptibility of the Arabian Gulf and adjoining sea areas
to harmful algal blooms (HABs) and impacts on fish health and food safety

Session chair: Qusaie Karam
1. Welcome & aims of the workshop – Qusaie Karam – Kuwait Institute for Scientific Research (KISR) (5 min)
2. Opening address – Sunny Ahmed (Deputy Ambassador for Kuwait) (5 min)
3. Global perspective on HABs, environmental drivers & impacts – Elisa Berdalet (IOC SCOR GlobalHAB program) (20 min)
4. Regional HAB events and impacts on fisheries/aquaculture in the Regional Organization for the Protection of the Marine Environment (ROPME) Sea Area (RSA):
o Sea of Kuwait – Environmental mechanisms associated with algal blooms in the Arabian Gulf - Yousef Al-Osairi (KISR) (20 min)
o Sea of Oman - Decision and Information System for the Coastal Waters of Oman - Ms. Suad Al-Bemanyah (Ministry of Agricultural Wealth, Fisheries and Water Resources, Oman) (20 min)
5. Break (15 min)
6. The status and trajectory of aquaculture in the Arabian Gulf and Sea of Oman – Patrick White FAO consultant (20 min)
7. Shrimp aquaculture and general aquaculture: an overview, challenges, and accomplishments - Sherain Al-Subaie (KISR) (20 min)
8. Environmental extremes and additional pressures on marine ecosystems in the RSA – Michelle Devlin (CEFAS) (20 min)
9. Linking environmental factors, HAB events and impacts on fish and shellfish - Adam Lewis (CEFAS), Ross Brown (University of Exeter) (20 min)
10. Discussion on sampling strategies, tools and data availability, integration and analysis (15 min)

DAY 2 (23 February, 12:00-15:00 UK time)
Developing early warning systems (EWS) for HABs for mitigating impacts on fisheries and aquaculture
Session chair: Ross Brown
11. Introduction and recap (from Day 1) on aims of the workshop – Ross Brown (University of Exeter) (5 min)
12. Understanding impacts of HABs on fish farms and vice versa based on lessons learned in:
o Chile - Jorge Mardones (CREAN) (15 min)
o Control of HABs in China using a modified clay approach - Isaac Yongquan Yuan (CAS) (15 min)
13. Existing HAB observation and EWS in the RSA
o Kuwait Territorial Waters - EWS for HABs and fish kill Incidents - Qusaie Karam (KISR) (15 min)
o Eastern Gulf and Sea of Oman - Gilan Attaran-Fariman (Chabahar Maritime University, Iran) (15 min)
14. Break (15 min)
15. Other observation and EWS for HABs o HAB Early Warning Systems in Chile - Alejandro Clément (Plancton Andino, Chile) (15 min)
o HAB Early Warning Systems in North America - Raphe Kudela (University of S California) (15 min)
o Changes and complexity of HABs in Asia - Patricia Glibert (University of Maryland) (15 min)
o HAB Early Warning Systems in the UK - Keith Davidson (SAMS) (15 min)
16. Break (15 min)
17. Discussion on next steps for further developing a HAB EWS for the RSA (30 min)
o What are key data/ knowledge gaps and research priorities?
o Data linking HAB occurrence and fish kills?
o Funding opportunities?
18. Sum up and close workshop (Ross Brown, Elisa Berdalet Po Teen Lim) (10 min)



Gulf HAB workshop videos and proceedings:

Part 1

Part 2

Part 3

Part 4

Part 5

Part 6

Gulf HAB workshop proceedings.pdf


PROJECT TITLE: Citizen Science Program in the Strait of Georgia, Canada

Scope: Regional

Type: Monitoring

Timeframe: January 2015 to December 2021                                                              

Program manager: Dr. Isobel Pearsall

Address: Pacific Salmon Foundation, 1682-300 West 7th Avenue, Vancouver, BC, V6J 4S6, Canada

E-mailThis email address is being protected from spambots. You need JavaScript enabled to view it.

Home page URL

Other key people:

Nicole Frederickson (program coordinator)

Svetlana Esenkulova (harmful algae component)



The goal of the Citizen Science Program in the Strait of Georgia is to collect and disseminate detailed oceanographic data. This program was implemented by the Pacific Salmon Foundation (PSF) with support from the Oceans and Networks Canada (ONC) and Department of Fisheries and Oceans (DFO). The program has been operating since 2015, and was endorsed by the GlobalHAB program in January 2020. Trained members of local communities (referred to as “citizen scientists”) collect information at ~55 defined locations (Fig. 1) on, or as close to, the same day approximately every two weeks between February and October, annually between 2015-2021. At each station, CTDs (conductivity, temperature, depth) are deployed and water samples are taken for nutrient analysis and phytoplankton taxonomy. The scope and coverage of this program are unprecedented; more details about this program and the CitSci dataset, as well as figures showing oceanographic conditions over 2015-2019, are provided in Pawlowicz et al. (2020). Data are stored at

Figure. 1 Map of the Strait of Georgia with CitSci program sampling locations in 2020.

                Different colours represent different patrols.


During six years of observations to date, heavy blooms of potentially harmful blooms were caused by Noctiluca scintillans (Fig. 2, 3), Heterosigma akashiwo, Pseudo-nitzschia spp., Rhizosolenia setigera, Gonyaulax spp., and Dictyocha spp. Investigation of the relationship between environmental factors and bloom dynamics is underway.

Figure. 2 Noctiluca scintillans bloom, Salt Spring Island, May, 2 2018. Photo by Michael Bahrey.


Figure. 3  Cell of Noctiluca scintillans with Chaetoceros spp. in food vacuoles,

                 Citizen Science sample. Photo by Svetlana Esenkulova



Pawlowicz, R., Suzuki, T., Chappel, R., and Esenkulova, S. 2020. Atlas of Oceanographic Conditions in the Strait of Georgia (2015–2019) based on the Pacific Salmon Foundation’s Citizen Science Dataset. Can. Tec. Rep. Hydrogr. Ocean Sci. 3374: vii + 116 p.

Esenkulova, S., Suchy, K., Pawlowicz, R., Costa, M., & Pearsall, I. Harmful algae and oceanographic conditions in the Strait of Georgia, Canada based on citizen science monitoring. Frontiers in Marine Science,1193.    

Annual reports of the harmful algae observations are published in the State of the Pacific Ocean:

Several reports were published in the Harmful Algae News:

  • Esenkulova, S., Pearsall, I., 2019: Citizen Science oceanography in the Strait of Georgia, Canada – an overview of five years operations. Harmful Algae News 63, 12-13.
  • Ecology of Alexandrium spp. in the Strait of Georgia, British Columbia, Canada 2015. Esenkulova, Pearsall, Novak, 2017: Harmful Algae News 56, 7-8.
  • Observations of Heterosigma akashiwo bloom and associated wild salmon lethargic behavior in Cowichan Bay, Canada, 2014. Esenkulova, Luinenburg, Neville, Trudel, 2014.  Harmful Algae News 50, 16-18.

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