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Helping aquaculture businesses save millions by predicting the risks of harmful algal blooms

3 July 2020

2 minutes to read

Helping aquaculture businesses save millions by predicting the risks of harmful algal blooms

The problem

Harmful Algal Blooms (HABs) pose an enormous threat to shellfish aquaculture and the marine industry. HABs form in coastal waters and release dangerous biotoxins which make shellfish unsafe to eat, preventing shell fishermen from harvesting their crop.

In summer 2018, shellfish farms in St Austell bay had to close for 18 weeks due to HABs, costing over £1million in lost sales. As HABs thrive in warm waters, occurrences such as this are set to increase with global warming. It is already estimated that HABs cost marine industries more than £30 million a year in the UK, while global impacts through lost sales and health costs are in the region of $8 billion per year.

The research

Marine research funded by the European Maritime and Fisheries Fund and led by Dr Ross Brown has uncovered environmental factors that increase the risk of HABs forming, which have been applied to the development of a statistical model, which can predict the risks of HABs developing.

The project began with extensive field work on shellfish growing sites around the South West Peninsula where HABs frequently occur, to establish why some sites are badly affected, and others are less impacted. It was revealed that the risks of HABs forming increased further west along the English Channel coast, due to differing circulation patterns and harmful species potentially entering from the Atlantic. The work also showed that warm, calm conditions causing thermal stratification (formation of distinct hot and cold layers in surface and underlying water), can provide extra stability for harmful algae to grow effectively.

The main environmental factors that were identified by the survey work to promote HABs were used to inform the predictive model.


Predictions will allow existing aquaculture businesses to mitigate the impact of HABs, by advising shellfish farmers when risks are coming. This will help to inform the timing of shellfish harvesting and safeguard food quality and human health. The model will be used to guide the placement of new infrastructure in the UK’s forthcoming Marine Spatial Plan for South West England, by locating new farms in areas that have a low risk of HABs.

A peer reviewed article on Assessing risks and mitigating impacts of harmful algal blooms on mariculture and marine fisheries, which was published last year, was co-authored by Elisa Berdalet, who is chair of GlobalHAB, an international programme sponsored jointly by the Scientific Committee on Oceanic Research (SCOR) and the Intergovernmental Oceanographic Commission (IOC) of UNESCO, which coordinates research into the risks and effects of HABs to inform science-based decision-making.

Ross and his team are now embarking on a further six month project with the Institute of Data Science and Artificial Intelligence (IDSAI) to advance statistical models to better predict the formation of HABs in South West England.


For more information please contact:

Nicola Rogers
Impact and Partnership Development Manager – Bioeconomy and Aquaculture


Dr Ross Brown


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