November 03, 2017 - Hallegraeff et al.HAB training

Call to Contribute to Global Harmful Algal Bloom Status Reporting

From 25 to 28 September 2017 sixteen HAB experts from 13 countries gathered at the headquarters of the IOC IODE (International Oceanographic Data Exchange) Programme Office in Oostende, Belgium (see group picture at the end), to receive training in data entry into the Ocean Biogeographic Information System (OBIS; and the Harmful Algae Event Database (HAEDAT; Editors within defined HAB regions were requested to collect publications associated with the occurrences of toxic algae, even with no recorded impact, and enter these records in OBIS. The aim is to trace reliable geographic ranges for the genera/species that are included in the IOC Taxonomic Reference List of toxic and ichthyotoxic algae ( This activity will complement the compilation of records of harmful events with impacts (including cases of intoxicated seafood, discolorations, mucilages, etc.) collected in HAEDAT, with new event data being entered from regions for which this information is currently missing. The effort of compiling and increasing data sets is being intensified in order to provide a substantial part of the basis for a first Global HAB Status Report.

This report series will provide the scientific community as well as decision makers with a reference on HAB occurrence and impacts on ecosystem services. IOC-UNESCO project partners include the International Atomic Energy Agency (IAEA), the International Council for Exploration of the Sea (ICES), the North Pacific Marine Science Organization (PICES) and the International Society for the Study of Harmful Algae (ISSHA). We hope that the establishment of these data bases will allow us to convincingly answer key questions on the probability of change in HAB frequencies, intensities, and geographic range resulting from environmental changes at local and global scales. While the available data sets are still incomplete, we here provide examples of analyses from HAEDAT (Figs. 1, 2, 4) and OBIS (Fig. 3) data. While the results are preliminary and conclusions are likely to be modified as more data become available, we present them as an encouragement for HAB workers to contribute to this important initiative.

Fig.1. Total number of HAEDAT records in the different OBIS regions of East Coast America, West Coast America, Caribbean Central America, Northern Europe, Southern Europe, Mediterranean, Australia/New Zealand, North Asia and Pacific. The regions of South America, Africa and South East Asia represent key missing data sets. Data as of 1/3/2017. Compiled by Laura Schweibold who worked for 6 months on a GHSR Masters project supervised by G.Hallegraeff.

Fig.2. Partitioning of 5136 global HAEDAT events into seafood toxins, high biomass water discolorations, fauna mass mortalities, and the further breakdown of seafood toxins into DSP, PSP, ASP, NSP, CFP, AZP and cyanotoxins. Data as of 1/3/2017. Compiled by Laura Schweibold.

Different regions and countries suffer from different types of HABs, and this is reflected in the way countries/regions enter their data. North America and Europe operate highly sophisticated shellfish toxin monitoring programs. PSP is the dominant seafood toxin syndrome in North America, NSP in the Gulf of Mexico and DSP in Europe. The effectiveness of these monitoring programmes is well reflected in the fact that only an estimated 1 to 10% of toxin-producing blooms lead to human poisonings. In contrast in less well monitored areas such as Australia/New Zealand and Central America up to 50 to 60% of toxin producing algal bloom events can lead to human victims. In the extreme, Pacific HAEDAT data are based exclusively on human ciguatera poisonings diagnosed by medical practitioners.

OBIS HAB species occurrence data are even more incomplete, and heavily biased by European records. Time series data for location records of the key target genera Dinophysis and Pseudo-nitzschia (Fig. 3) exhibit an increase in frequency over the past 30 years, undoubtedly reflective of increased awareness and monitoring effort.

The ICES-IOC Working Group on Harmful Algal Bloom Dynamics (WGHABD) have used HAEDAT to map the distribution of harmful algal events during the period from 2014 to 2016 in the North Atlantic. Examples for PSP, DSP and AZP are presented in Fig 4. These maps highlight the regional aspect to harmful algal events in the North Atlantic area with PSP events recorded across the USA, Canada and Europe during the three year period, a higher incidence of DSP events recorded in Europe, and AZP events restricted to the SW coast of Ireland with a low number also recorded in the UK and Norway.

Planned outputs of the Global HAB Status Report include: (1) a dedicated session during ICHA18 in Nantes in October 2018; (2) a special issue of Harmful Algae in 2019; (3) regular 2-3 year reports on the status of global HABs, the first of which will be launched in Nantes.

Follow the development of the Global HAB Status Report at and see who is involved and how you may engage.

Fig.3. Time series of OBIS location records of the HAB genera Dinophysis and Pseudo-nitzschia between 1950 and 2014, with the time of description of their associated syndromes DSP and ASP indicated. Records are heavily biased towards Europe.

Fig.4. Maps showing the incidence of PSP, DSP and AZP during the period 2014 to 2016 in the North Atlantic as reported by the ICES-IOC WGHABD. Areas such as Northern Canada and Greenland are not routinely sampled and countries with pink borders have still to submit data. Data from the Pacific shorelines of Canada and the USA are also included.


We thank Ward Appeltans and Pieter Provoost at the IOC/IODE Project Office for hospitality and technical support. The meeting was funded by the Flanders Government through the Ocean Teacher Global Academy and DIPS-4-ocean assessments projects.


Gustaaf Hallegraeff, Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia

Eileen Bresnan, Marine Scotland Marine Laboratory, 375 Victoria Road, Aberdeen, AB11 9DB, United Kingdom

Henrik Enevoldsen, IOC Science and Communication Centre on Harmful Algae, University of Copenhagen, 2100, Copenhagen, Denmark

Laura Schweibold, Universite de Bretagne Occidentale, Institut Universitaire Europeen de la Mer, 29280 Plouzane, France

Adriana Zingone,Stazione Zoologica Anton Dohrn Villa Comunale, 80121 Napoli, Italy