Harmful Algal Blooms

Harmful algal blooms (HABs) are a natural phenomenon in which microscopic algal cells reproduce rapidly, causing a population explosion. Blooms can vary in magnitude, reaching cell concentrations in the millions per liter. The massive number of cells can cause water to appear discolored. The best-known example of this discoloration is red tide.

 

High temperatures and excess nutrients drive the formation and proliferation of HABs. However, blooms do not occur exclusively in warm waters. Algal blooms form in marine, brackish, and freshwater environments ranging from tropical seas to polar regions. Various algal taxa form blooms. Dinoflagellates, cyanobacteria, diatoms, and raphidophytes are among the most common HAB taxa.

 

Blooms are considered harmful when they create toxins. Algal toxins can cause illness in fish, birds, and mammals, including humans. Diarrhetic shellfish poisoning results from eating seafood contaminated with algal toxins. Algal toxins like those produced by red tide may aerosolize and cause respiratory illness. Other algal toxin-related illnesses, such as ciguatera, can be life-threatening.

Visit the links below to learn more about HABs

 

U.S. National Office for Harmful Algal Blooms

 

EPA – HABs in Waterbodies

 

NOAA – What is a Harmful Algal Bloom

 

• Harmful Algal BloomS Observing System
• National Centers for Coastal Ocean Science – Harmful Algal Blooms

 

Intergovernmental Oceanographic Commission – HABs Programme

 

CDC – Harmful Algal Blooms and Your Health

 

National Institute of Environmental Health Sciences

 

American Veterinary Medical Association