Ohio State University Extension http://agnr.osu.edu

Agriculture and Natural Resources

Ohio State University Extension

Harmful Algal Blooms

What are harmful algae blooms?

Harmful algal blooms (HABs) are so named because they can produce toxins (or poisons) that can cause illness or irritation—sometimes even death—in pets, livestock, and humans. The term “algae” is somewhat misleading since HABs are actually HAB at Stone Labcyanobacteria, which are commonly referred to as “blue-green algae,” and are not true algae. These organisms act like many other plant and use photosynthesis to capture sunlight but unlike most plants and algae some can fix their own nitrogen from the atmosphere.  Most blooms in Lake Erie and GLSM are types of cyanobacteria that cannot fix nitrogen. At sometimes we do see nitrogen fixing blooms.

Factors that can contribute to HABs include:

  • excess nutrients (phosphorus and nitrogen)
  • sunlight
  • low-water or low-flow conditions
  • calm water (low-wind conditions)
  • warmer temperatures
  • low salinity
  • selective grazing (avoiding cyanobacteria)by zooplankton or zebra/quagga mussels

For more details on Harmful Algal Blooms in Ohio see:

Where can I find HAB advisory Information for waters I use?

Ohio EPA has established thresholds and initiates testing when cyanobacteria are visually present in Ohio’s public waters. The current advisory status of Ohio beaches and water bodies can be found by visiting the site Ohio EPA HAB Advisories . The site also shows current criteria used for the various alerts posted.

Predicting HAB’s on Lake Erie?

NOAA uses data on Phosphorus loading in the spring as a predictive model for the intensity of the bloom that is release in early July then provides week monitoring with satellite data to update HAB formation and movement for the Western Lake Erie Basin. Refer to NCCOS's website for the most recent information.

Looking for more information on Ohio Watersheds?

One resource for those wanting more information on Ohio Watersheds is the Ohio Watershed Network Ohio Watershed Network which provides information to community members and natural resources professionals who want to protect the resources in their watershed.