Maps Highlight Coastal Areas at Risk from Harmful Algae

Maps Highlight Coastal Areas at Risk from Harmful Algae

Harmful algae blooms pose a growing threat to coastal communities, fisheries, and marine ecosystems. The good news is that scientists' ability to predict them has significantly improved - as long as they have good data on where, when, and under what conditions specific algae species flourish. The bad news is that most research to date has focused narrowly on well-resourced parts of the Northern Hemisphere. There has been little-to-no monitoring along vast stretches of coastline around the world.

In the absence of limitless resources, decision makers need to know where to prioritize sampling efforts. Researchers at Bigelow Laboratory for Ocean Sciences recently completed a project with the UN Food and Agriculture Organization to figure that out. They built several global maps that use geographically limited databases of existing monitoring information to predict where environmental conditions are conducive for fish-killing blooms in data-poor parts of the ocean.

This was just the pilot project, but the ultimate hope is to create a tool that can be integrated with FAO's global monitoring platform, Earth Map. Overlaying maps of environmental conditions with population information and other hazards would illuminate the drivers and consequences of these blooms to help guide investments in algae monitoring and early warning systems.

"There's next to no data across so much of the world, which leaves big gaps in our understanding of the risks posed by harmful algae blooms," said Senior Research Scientist Nick Record. "We know algae are really diverse in their biology, ecology, and social context, so there isn't a one-size-fits-all modeling approach. But this is an important first step to figuring out where to focus our attention based on where conditions might be right for a bloom."

FAO, in partnership with the International Atomic Energy Agency and the UN's Intergovernmental Oceanographic Commission (IOC), released technical guidance in 2023 for implementing early warning systems for harmful algae. Through that work, Record, who directs Bigelow Laboratory's Tandy Center for Ocean Forecasting, and Research Associate Johnathan Evanilla were brought into a number of collaborations to translate the technical guidance into actionable tools for preparing for and responding to algae blooms.

Record describes the maps they've created so far as a "proof of concept." One of the limitations, he points out, is that they're focused on the algae species that are most "abundant" based on existing datasets, which means the information is skewed toward certain parts of the ocean. As the team looks for funding to continue the work, one of the goals is to consider a wider range of algae species, including those that might be more common along less monitored coastlines.

That said, when they compared the maps to data Bigelow Laboratory scientists have collected close to home, the results were promising.

"There's almost no information in existing databases on the harmful algae species we see in coastal Maine, so our models weren't trained on much Gulf of Maine data," Record said. "Yet, the maps we produced match well with the patterns we've seen in this system and the species we know are here through our independent research, which is encouraging."

The recent round of work with FAO is part of a portfolio of international projects the Tandy Center team are pursuing to help build capacity for early warning systems. In 2024 and 2025, for example, Record and Evanilla participated in technical workshops in Namibia and Morocco. They've continued to do virtual data training with those stakeholders and are working with IOC Africa to potentially expand the workshops to other countries.

Both projects, Record says, reflect the powerful benefits of these collaborations - and the extensive reach of Bigelow Laboratory's algae expertise. Maine's advanced shellfish toxin monitoring program, born out of a partnership with the Maine Department of Marine Resources, has become a valuable model for other countries interested in algae bloom forecasting. And the manager of Namibia's primary oyster hatchery, who Record met during last year's workshop, learned cultivation techniques through a Bigelow Laboratory professional development program decades ago.

At the same time, the institute's forecasting efforts have been improved by these experiences working in new places.

"Through these partnerships, we're learning more about what data products exist, what different questions and priorities people have, and where our models do and don't apply, all of which makes our work stronger," Record says. "Sharing knowledge and learning from each other is how we're going to find common solutions to these serious challenges of the future."

Photo Captions

Photo 2: A screen capture of the risk map tool the team produced, zoomed into southern Africa, showing fish kill events and other risk layers (Credit: Bigelow Laboratory).