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What are HABs?

Harmful algal blooms (HABs) occur when a species of algae grows at an exponential rate, rapidly increasing its concentration in a body of water. Algae blooms can become harmful in multiple ways. 

In Alaska, there are specific species of planktonic algae that produce toxins that can be harmful to people, animals, and the surrounding ecosystem. These toxins can cause severe health problems when ingested, and may be fatal if concentrations are high enough. 

When do HABs occur?

In conditions of favorable weather patterns, photoperiod, and adequate nutrient availability, these algae flourish or "bloom". These blooms flood the marine ecosystem with an abundance of algae, which produce enough toxins to accumulate in the animals that eat them, such as shellfish, fish, and crabs. This poses severe risks to people and animals consuming these organisms.

Why are HABs important to monitor?

HABs can cause widespread damage at the species, community, and ecosystem level. These harmful ecological disturbances can endanger public health and disrupt local economies. Because of this, it is crucial to monitor where HABs are forming all along commercial, recreational, and residential coastal areas.  A monitoring system can give the public real-time data to best determine the risk level for recreational and subsistence harvest of shellfish and other marine organisms.

What can you do to prevent illness?

Our monitoring program produces weekly reports of the algae species observed in the waters surrounding Southcentral Alaska. You can check these reports to inform yourself about the levels of algae in the water.

We also conduct regular shellfish testing in the region to determine the levels of toxins in local shellfish on a weekly basis. You can check these reports to inform yourself about the levels of algal toxins in shellfish.


*Chugach Regional Resources Commission and the Alutiiq Pride Marine Institute assume no responsibility for safe shellfish harvest. Harvesters must do so at their own risk.


Paralytic Shellfish Toxin Testing

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