Stop Harmful Algae Blooms

These blooms decimate aquatic life, pollute freshwater supplies, and create “dead zones” that severely damage ecosystems

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    Track and document the occurrence of these potentially harmful algal blooms yourself

    CyAN – Android app store, USA

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    Created in partnership with

    The Oxygen Project has teamed up with Vivobarefoot to take action and raise awareness around the growing problem of harmful algae blooms (HABs). Toxic for humans, animals and plant life, these algae blooms are choking our planet’s waterways and creating ‘dead zones.’ Want to #StopHABS? Join us, sign our letter and learn more!

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    Frequently Asked Questions

    What is an algae bloom?

    Algal blooms occur when environmental conditions allow explosive growth of phytoplankton — a bloom — that can change the color of ocean water. In order for a bloom to occur, there has to be just the right “recipe” of environmental factors:

    1. Bright sunlight
    2. High nutrient levels
    3. Calm waters (low wind and circulation)
    4. Limited number of grazers or predators
    5. Other environmental factors can be temperature and salinity, which influence HABs differently but may help in determining the sources of blooms.

    Most algal blooms are natural and essential components of any marine ecosystem — and most are nontoxic. However, harmful algal blooms can harm or kill marine animals, contaminate shellfish and threaten human life.

    (Source: Central and Northern California Ocean Observing System)

    What are harmful algae blooms (HABS)?

    Harmful algal blooms are blooms of species of algae that can have negative impacts on humans, marine and freshwater environments, and coastal economies. These blooms occur when phytoplankton, which are tiny microscopic algae, grow quickly in large quantities while producing toxic or harmful effects on people, fish, shellfish, marine mammals, and birds.

    (Source: NOAA)

    What areas are prone to harmful algae blooms (HABS)?

    Harmful algal blooms are found in bodies of freshwater, marine (salt) water, and brackish water around the world. They occur in waters across the the planet.

    1. Fresh water —In 2014, a national survey found that over 50% of responding states in the United States (38 states and the District of Columbia) reported that harmful algal blooms are present every year in some of their lakes or other freshwater bodies.

    2. Marine water—All coastal states in the United States have experienced harmful algal blooms, including Hawaii and Alaska. Harmful algal blooms in the U.S. and around the world have been associated with food poisoning. Imported seafood has been implicated in a number of HAB-associated poisonings in inland areas.

    3. Brackish water—Harmful algal blooms have been reported in brackish waters, including estuaries and coastal waters, in the United States.

    (Source: CDC)

    What does an algal bloom look or smell like?

    An algal bloom can look like foam, scum, mats, or paint floating on the surface of water. Some blooms are not visible at the water surface. Water bodies with an ongoing bloom may look blue, green, brown, yellow, orange, or red. When organisms in a bloom die and decompose, they can release unpleasant odors (like the smell of rotting plants).

    (Source: CDC)

    Why are HABs dangerous?

    1. Produce toxins that can poison humans, fish, seabirds, aquatic animals, livestock, wildlife, and household pets (such as dogs) that are near the water, drink the water, or swim in the water.

    2. Cause illness when a person or animal eats fish or shellfish contaminated with algal toxins.

    3. Become dense enough to keep sunlight from reaching the lower depths of the water.

    4. Remove the oxygen from the water as it decomposes, starving fish and plants of oxygen, and damaging the local ecology.

    (Source: CDC)

    Sign the open letter to the UNESCO (United Nations Educational, Scientific and Cultural Organization) to prevent pollution of world heritage lakes.