Algae & Microscopic Organisms

The lake may look sterile and devoid of life now that the Grass Carp have removed much of the aquatic plant growth, but actually the lake is teeming with small organisms. A good balance of these organisms is needed to provide food for larger organisms, such as birds and fish. Viewing lake water under a microscope can open up a whole new world of exploration. The Preservation Association of Devils Lake invites the public to attend our annual meeting (usually in June) to learn more.

What is the scum floating on the lake? It could be a blue-green algae bloom. Algae blooms can occur when there are nutrients in the water column and the temperature is warm. Winter storms and wave action from boats can stir up the lake bottom, releasing nutrients into the water column. If other conditions are right, an algae bloom can occur. Algae can be an indicator of limited water quality (pollution). Anabaena is a type of blue-green algae that can discolor the water and give off a putrid odor when the cells die off and decay. Devils Lake has seen an increase in the frequency of algae blooms from undesirable species, and a decrease in the diversity of desirable algae species. Algae in the lake can affect water clarity. Secchi disks are round, black and white disks that are lowered into the water from the surface. Clarity is gauged by how far down the disks go into the water before disappearing. Report algae blooms to the Devils Lake Water Improvement District (DLWID) at 541-994-5330.

Phytoplankton surveys from July 17, 1981 identified the following alga: Fragilaria crotonensis, Cryptomonas erosa, Anabaena sp., Kephyrion spirale, Ankistrodesmus falcatus, and four others.

Blue-green algal blooms - potential for toxins
North American Lake Management Society Blue-green algae page

Blue-green algae blooms on Devils Lake can occur when conditions are right. Most are non-toxic. However, you should avoid swimming in an area where there is an abundance of algae blooms. Some algae toxins can be harmful to pets, so keep your pets away from algae blooms.

The Oregon Department of Human Services has a download pdf brochure, download pdf flyer about algae, and a web page at You can subscribe to receive blue-green algae advisories by email from the website.

Washington State Department of Health
- Cyanobacteria were previously grouped with algae but are now classified as bacteria after analysis of cell structure and cell division. They differ from other bacteria in that they contain photosynthetic pigments similar to those found in algae and plants. Although they are predominantly photosynthetic (light-dependent) organisms, they are also capable of using organic compounds as a source of energy. Some cyanobacteria have a specialized structure called a heterocyst that can fix molecular nitrogen. The ability to fix nitrogen gives these species a competitive advantage over other algae. Many cyanobacteria have gas vacuoles that allow them to remain in suspension and migrate to surface waters where there is plenty of light for photosynthesis. On the surface, colonies may clump together and form a scum which can cause water quality problems in lakes.

Case Studies of algal blooms
Toxic Algae in Lake Sammamish, Washington State

9/19/97, King County Water and Land Resources - The swimming area of Lake Sammamish State Park had sufficient algae to tint the water a bright green and extensive surface film was present at the beach. A grab sample of this surface bloom was collected from within the swimming area of the park and on Saturday was carried to Dr. Michele Crayton, an algal toxicology expert at Pacific Lutheran University. The cyanobacteria blooming in the lake was primarily Microcystis aeruginosa and tested positive for toxicity.
    Not all cyanobacteria blooms are toxic, and even blooms caused by known toxin producers may not produce toxins or may produce toxins at undetectable levels. It is not known what triggers toxin production. Recent studies have shown the probability that an individual bloom containing Anabaena, Microcystis, and/or Aphanizomenon will be toxic could be between 45 and 75% (Toxic Cyanobacteria Blooms; A Field/Laboratory Guide, Dr. M. A. Crayton).
    In 2003, King County initiated toxicity testing on samples collected routinely from Lake Sammamish, Lake Washington, and Lake Union.

State Agencies Sign on as Cooperators in the Diamond Lake Restoration Project (Roseburg)
11/19/03, In addition to the overpopulation of tui chub and decline of the rainbow trout fishery, Diamond Lake also has experienced toxic algae blooms for three consecutive summers. Human health risks associated with blooms of the blue-green algae Anabaena flos-aquae prompted the Forest Service and the Douglas County Health Department to implement lake closures for portions of all three summers.
    In 2003, Diamond Lake experienced increased water quality problems and health risks with the appearance of a second toxic blue-green algae species, Microcystis aeruginosa. Both of these algae species produce toxins...

Lost Creek Lake blue-green algae testing
Ore. lake could have advisory lifted by the 4th - June 22, 2009
TRAIL, Ore. (AP) -- The U.S. Army Corps of Engineers is trying to get a health advisory lifted at a popular reservoir before the start of the Fourth of July weekend.
Tests this week on water samples collected Friday could prompt state health officials to quicken the lifting of their advisory against contact with water at Lost Creek Lake, northeast of Medford.
The advisory took effect earlier this month after the discovery of high levels of a blue-green algae known as anabaena flos-aquae.
The Oregon Department of Human Services does not typically end such advisories until two weeks after tests show levels below thresholds deemed safe by the World Health Organization. But the state can speed the process if other tests also show safe levels of two algae-related toxins that can sicken people.
The U.S. Army Corps of Engineers ordered the extra tests, which cost about $400, in hopes the advisory will be lifted before the holiday weekend.
" We realize there's an economic impact when you have a health advisory," said Jim Buck, the Corps' Rogue Basin project manager. "We're in the recreation business. That's part of our mission. We want to try to preserve the recreational benefit and the economic benefit during a major holiday weekend."
Health officials issued the advisory after water sampled from the swim area showed levels of the blue-green algae as high as 16 times the threshold considered safe for contact.
When it dies, the algae, which actually is a bacteria, releases neurotoxins that can cause symptoms ranging from a skin rash and dizziness to rapid death. Documented reactions, however, have been extremely rare in Oregon.
It is the fourth consecutive year an algae bloom has hit Lost Creek Lake. The one last fall lasted four months.
This month's bloom could be much shorter. Buck said the algae dissipated noticeably during the past week, leading to Friday's sampling.
An end to the advisory would be good news for businesses that make their money from the swimmers, water-skiers and anglers who use the lake that consistently ranks among the state's busiest.
" We need the whole season here but the Fourth of July, of course, is one of our biggest weekends," said Doni Swearingen, who manages the Lost Creek Marina at Stewart State Park, whose campgrounds always fill that holiday.
" I'm going to think positive and assume it's going to be gone," Swearingen said.

Algae bloom at West Harwich, Massachusetts
08/18/04, The Harwich Natural Resources Department is investigating an algae bloom that was reported on West Reservoir in West Harwich, Massachusetts on Monday.

Great quote from a news article after Diamond Lake was closed for 3 weeks due to algal blooms. "The lake isn't meeting state water quality standards. It isn't meeting the recreational and economic expectations of Oregonians."
8/5/02 Dave Ehrhardt, Editorial Editor - Rogue River Press on the Oregon Department of Fish & Wildlife website.

Potential blue-green algae toxin types:
1. Endotoxins - skin rashes, irritation of the eyes, and gastroenteritis
2. Neurotoxins - damage nerves and can cause muscle tremors, especially in the muscles animals and people need to breath
3. Hepatotoxins - damage the liver

2008 Cyano-watch by the Devils Lake Water Improvement District (DLWID) -

• 9/24/08 - The RED Health Advisory posted August 14, 2008 remains in effect. Severely high levels of toxicity have been documented in nearly all of the shoreline sample sites.  Values in excess of 100 ppb were recorded. The current situation on Devils Lake has actually gotten significantly worse, and therefore water contact is seriously warned against.  The resurgence of the cyanotoxins is likely due to the increasing presence of different toxigenic strains of cyanobacteria in Devils Lake. Cyanobacteria such as Microcystis and Anabaena have been documented. These organisms are among the most toxic cyanobacteria known to exist.  As a result, the highest documented concentrations of Microcystin to date have been seen.  An initial screening of samples collected on 2008-09-22 showed that all the samples were greater than 10.0 ppb. Further analysis of these same samples has shown some sites in excess of 100 ppb (see table below). The Recreational Water Use Standard for Microcystin is 8 ppb, and thus samples from Devils Lake may be greater than 13 times the Oregon standard.
• 9/16/08 - The Red Health Advisory posted August 14 remains in effect. 
Toxicity analysis of a sample collected from the campground moorage dock proved to be much greater than expected given the previous values.  The undiluted sample was determined to contain greater than 5 ppb of Microcystin, a known liver toxin.  The Recreational Water Use Standard established by Oregon DHS for Microcystin is 8 ppb and thus the sample may actually exceed that value.  However, analysis of samples for a separate, more dangerous toxin, Saxitoxin proved to be undetectable (Limit of Quantification for Saxitoxin is 0.015 ppb) at all sample sites.  This is the first Saxitoxin analysis done on Devils Lake. Resampling and further analysis will be conducted within 1 week. per DLWID.
• 9/3/08 - The health advisory shall remain in effect until September 16th, 2008, provided cyanobacteria do not make a resurgence. 
• 8/14/08 - The cyanobacteria bloom in Devils Lake has progressed to the point to warrant a Health Advisory.  This is the highest level alert the Devils Lake Water Improvement District has established in its CYANO-WATCH program
and is consistent with Oregon Department of Health and Human Services protocol for cyanobacteria posting.  Scum formation of toxicgenic species has been seen at many of the public accesses as a result of the free-floating cyanobacteria washing ashore.  Scums from cyanobacteria have not been seen in the broad lake, as typically only the shorelines are affected at this level.  Toxicity testing confirms that the highest risk areas are those shoreline areas with scum present, and that the broad lake is of much less of a risk area
• 8/3/08 - DLWID has issued a yellow caution for cyanobacteria.



High bacteria levels have been found in Thompson Creek at the north end of Devils Lake. The site is tested for bacteria.
Devils Lake is on the state's 303 (d) list for impaired water bodies for pH, and chlorophyl a during the summer, and bacteria in Thompson Creek annually. The goal is to have Devils Lake removed from the 303 (d) list.

For information about E. coli bacteria see water quality.

It is beyond the scope of this website to mention every small organism. One species of interest is the Fairy Shrimp (Anostraca), a tiny, crustacean found in Devils Lake. They are abundant in Rock Creek, a tributary of Devils Lake where coho salmon spawn.

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Lincoln City, OR 97367