Cyanobacteria in Ponds & Lakes

Images of cyanobacteria under microscope and how it appears in the water.

A type of blue-green algae, is found in damp soil and in shallow water as plankton. Dolichospermum can be found as a colony or as single cells. Colonies of Dolichospermum/Anabaena are similar in appearance to Nostoc. Cells resemble beads or barrels with irregular heterocysts, cells that fix nitrogen. The heterocysts are larger than the normal cells are irregularly dispersed in the colonies. Dolichospermum will cause blooms during summer months or months with increased temperatures.

Dolichospermum can produce a number of cyanotoxins including microcystin, anatoxin, cylindrospermopsin, and saxitoxin.

A type of blue-green algae, is unicellular but can form colonies with hundreds of cells. Each cell is spherical or ovoidal in shape, but the colonies can vary in appearance. When the colonies form, they float to the surface of the water. The large collection on the surface of the water is referred to as a "bloom." Microcystis aeruginosa is found in freshwater with high nutrient levels. Microcystis is a type of bacteria, meaning it can withstand drastic environmental changes, including temperature.

Microcystis can produce the cyanotoxins microcystin and anatoxin.

Microcystis bloom

A type of blue-green algae, can be found in soil or floating in calm water. The nostoc in this image was stained red for easier identification and viewing. Colonies of nostoc can be as large as a golf ball. Within the colonies, spherical cells are linked in chains and held together in a gelatinous structure. Similar to Anabaena, Nostoc has heterocysts which fix nitrogen.

Nostoc can produce the cyanotoxin called microcystin.

A type of blue-green algae, found in freshwater at various temperatures, including hot springs. Oscillatoria can be found in tangled mats or as one cell. Oscillatoria moves through water by secreting mucilage to push itself in the opposite direction.

Oscillatoria can produce the cyanotoxins microcystin and anatoxin.

A type of blue-green algae, found in freshwater streams, ponds and lakes. Phormidium can be found in tangled mats or free-floating in water. Phormidium consists of a fine, smooth filament. The connected cells are square, barrel shaped. The end of the cell is often tapered.

Phormidium can produce the cyanobacteria toxin anatoxin .