Algae are found in virtually every marine and freshwater system on the planet. They range from single-cell, microscopic organisms to leafy seaweeds. Like other kinds of algae, cyanobacteria occur naturally in freshwater environments and are vital to the function of aquatic ecosystems. However, excessive growth of this single-cell organism can lead to “blooms” that may cause serious harm to freshwater habitats and human and animal health.
Read the full story below, written by Save Our Wild Salmon’s Outreach Coordinator Abby Dalke.
Photo by: LightHawk / Dr. Judy Parrish
Algae are found in virtually every marine and freshwater system on the planet. They range from single-cell, microscopic organisms to leafy seaweeds. Like other kinds of algae, cyanobacteria occur naturally in freshwater environments and are vital to the function of aquatic ecosystems. However, excessive growth of this single-cell organism can lead to “blooms” that may cause serious harm to freshwater habitats and human and animal health.
Bloom-forming cyanobacteria is called Microcystis – a toxin that affects the liver and is responsible for the most human and animal poisonings. Direct exposure to water containing Microsystis can lead to headache, sore throat, vomiting, nausea, diarrhea, and pneumonia, tumor development, liver failure, decreased sperm count and motility, and possibly cancer.
What conditions lead to toxic algal blooms? Warm, slow-moving water and excessive nutrients via runoff. This is certainly the case on the lower Snake River in eastern Washington, where four dams create a series of reservoirs that regularly exceed water temperature standards established to protect migrating salmon and steelhead.
In late summer 2023, a massive harmful algal bloom covered at least 30 miles of the lower Snake River. To prevent annual ever worsening toxic algal blooms fueled by climate change, the root causes must be addressed. For the lower Snake River, it means removing four dams and restoring a cold, clean, free-flowing river.