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Tackling Harmful Algal Blooms

Earlier this year, an interagency working group released a research plan and action strategy for combating harmful algal blooms.

We all know that plants and algae are important—not only on land, but also in the water. They provide the oxygen we breathe, dispose of the carbon that we put into the air and are the base of our food web. But there can be too much of a good thing.

Algal “blooms” occur when colonies of microscopic algae—simple, plant-like organisms that live in the sea and freshwater—grow out of control. Algal blooms can occur naturally, but in most cases they result from nutrient pollution. Various types of algae produce toxins and can also clog fish gills, block light from bottom-dwelling plants and become a hazard to people and wildlife. We refer to these types of events as harmful algal blooms (HABs).  

Hypoxia, or low-oxygen conditions, can result when algal blooms decompose, typically in the bottom water as the algae sink from the surface. Hypoxic areas, or dead zones, are regions where the oxygen levels in water are too low to sustain most forms of life. This threatens shellfish and other animals incapable of escaping the dead zone and affects the food and habitat sources of those that can.

HABs and hypoxia pose risks to human and animal health, and significantly impact marine and freshwater resources, ecosystems, recreation and coastal economies.  HABs and hypoxia manifest themselves differently across the country, but every state is affected by HABs or hypoxia in some way.

The National Oceanic and Atmospheric Administration (NOAA) and the Environmental Protection Agency (EPA), as co-chairs of an interagency working group under the National Science and Technology Council, just took an important step towards addressing HABs and hypoxia. The group developed an action strategy, Harmful Algal Blooms and Hypoxia Comprehensive Research Plan and Action Strategy: An Interagency Report, to improve our collective understanding of HABs and hypoxia, their causes and effects, and the testing and research methods we employ in studying and addressing these events.

The action strategy, which was submitted to Congress this past February, was developed by the working group with input from stakeholders from academia, local government agencies, and affected communities as part of the Harmful Algal Bloom and Hypoxia Research and Control Act (HABHRCA).

Immediate and long-term coastal impacts caused by HABs and hypoxia challenge our ability to sustain healthy coastal communities and ecosystems. The interagency working group is identifying community risks and vulnerabilities, and working with decision-makers to identify science-based solutions that improve our collective ability to address threats from HABs and hypoxia.

Local officials in coastal communities need accurate and scientifically sound information, which NOAA and EPA provide, to make informed decisions that safeguard public health, protect coastal ecosystems and strengthen economies.

The action strategy expands collaborations in research, management, and policy arenas as our Federal agencies work to improve coastal resilience through ecological-forecasting approaches that better inform stakeholders and enable science-based decision-making. Now it is time to roll up our sleeves and focus on implementing this coordinated strategy to control and mitigate HABs. In doing so, we look forward to our continued dialogue with communities, resource managers, and our science colleagues. 

W. Russell Callender is Assistant Administrator of NOAA’s National Ocean Service.

Joel Beauvais is Deputy Assistant Administrator of EPA’s Office of Water.

Beth Kerttula is Director of the National Ocean Council.