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Cyanobacteria Harmful Algae Bloom (CyanoHAB) Photo Gallery

Identifying CyanoHABs

CyanoHABs can look many ways, and it's important to know how to recognize them to stay safe. There are 2 types of blooms: 

  • Planktonic blooms are found floating in the water. They often look like spilled paint or scum on the water's surface. These blooms look bright green or blue-green, like thick pea-green soup, or like white or brownish-red foam or scum.
  • Benthic blooms are found on the bottom of lakes and rivers. They can be attached to sand, rocks, or aquatic plants. Benthic mat material can also separate and float to the surface of the water. These detached mats can build up along the shore. They can be green, blue-green, or brownish-red.

This page has examples of both types of cyanoHABs and the different ways they can look. More photos can be found on the Interstate Technology Regulatory Council's website.


Planktonic Bloom Examples

Below are photos of planktonic cyanoHABs in Oregon waterbodies.

A pond with bright green water. The top of the water looks like spilled paint.  A pond with pea green water. A pond with brown and green water.

Water with a brown appearance. Green cyanobacteria drying on the shore.A pond with brown and green water. Water off a dock that looks like bright green paint has been spilled on it.  Water with the appearance of green spilled paint. Green water that looks as if paint has been spilled on top.


Benthic Bloom Examples

Below are photos of benthic cyanoHABs in Oregon and Washington waterbodies. 

A rock covered in what looks like brown algae. Rocks covered in a benethic bloom. It looks like brown algae.  

Photo credit: Benton-Franklin Health District

Tiny pieces of brown benthic mats on the shore. 
Photo credit: Ian Waite
A benethic bloom that appears like many small brown pieces on the sand underwater.

Photo credit: James Morrill