Algae Blooms Beautiful and Deadly

Blue Green Algae


Cyanobacteria, also known as blue-gree algae, was one of the original life forms on Earth. Using sunlight to make food, they may have been created the oxygen we breathe.

However, poison toxins produced by cyanobacteria are responsible for causing illness and death to those who breathe, drink, or even touch the toxin.

When something goes awry in the environment, it is usually caused by humans. The increases in cyanobacteria is no different. 

For some time, human-made sources of nitrogen and phosphorus encouraged larger blooms. Warming water temperatures caused by climate change actually does two things: it fuels cyanobacteria species while suppressing the growth of less harmful algae.

Harmful algal blooms (HABs) of cyanobacteria occur in approximately 35 states, with recent accelerated growth in 4 states.  The impacts include odor at the bloom, problems of bad tasting and smelling drinking water. Animal deaths, problems at fish hatcheries and reduced recreational opportunities round out problems.

Source: The Rise of Cyanobacteria in Freshwater Resources

Red Tide

Lingulodinium polyedrum, one type of dinoflagellates that cause red tide, have been spotted off the beaches in San Diego.  At night, the dinoflagellates are bioluminescent, so surfers and swimmers are wading in the stinking brownish waters to enjoy the blue light as their fingers or boards stroke the water. A wave crashing on the shore is something for people to watch.

While this particular algae does not cause harm to humans, it is harmful to fish and invertebrates. It damages or clogs their gills. The algae may form large blooms that, when they die and decay, the result is a dead zone (area of oxygen depletion) in marine environments. Dense blooms block sunlight that are needed by beneficial algae and sea grasses.

Sources: Red Tide Off California Coast Creates Blue Glow and Harmful Algal Bloom

Other HABs

Microcystis caused problems in Florida last Fall.

The algae, which kills fish, makes the water bright green and smell like raw sewage is highly toxic. Health authorities say you should not touch, drink it or swim in it. The algae in the water can give you rashes, respiratory problems, and even kill you.

Source: Toxic Algae Turning Florida Rivers Green