DENVER (CBS4) – Colorado Parks and Wildlife officials say an estimated 800 fish have died at Sloan’s Lake in the last week. CPW says recent hot temperatures have caused dissolved oxygen levels at the lake to plummet, depriving fish of oxygen.
Sloan’s Lake (credit: CBS)
The water temperature at the lake reached 79 degrees this week, according to CPW. An aquatic biologist also observed that the dead fish showed indications of a lack of oxygen.
Fish kills can be observed in summer months, and usually happen during prolonged periods of hot temperatures. Officials are also warning about the potential for toxic algae this time of year at Colorado lakes and reservoirs.
So far this summer, the state has found toxic algae in Prospect Lake in Colorado Springs, Barr Lake, Cherry Creek Reservoir, and Steamboat Lake. Officials say the algae is likely is present in other lakes and slow-moving waters as well.
According to the Colorado Department of Public Health and Environment, the blue-green algae is common and natural to Colorado waters, but it can harm people and be fatal to dogs and other animals.
A photo of algae at Cherry Creek Reservoir that tested positive for toxins in July. (credit: CPW)
“If you suspect toxic algae is present, do not let your kids, pets, or livestock touch or drink the water — when in doubt, stay out,” said Kristy Richardson, state toxicologist. “If any person or animal has had contact with the water, make sure they shower immediately and watch for symptoms.”
The state has been notified of several possible cases of illness associated with toxic-algae this summer. Symptoms include skin rash, gastrointestinal upset, fever, headache, sore throat, muscle, and joint pain. Symptoms for pets include vomiting, diarrhea, loss of appetite, abdominal swelling, stumbling, seizures, disorientation, or difficulty breathing.
To determine if an algae bloom is toxic, officials use lab tests and test strips. Toxic algae can resemble thick pea soup, spilled paint on the water’s surface, and/or create a thick mat of foam along the shoreline.
If you see possible signs of toxic algae:
- Keep kids and animals out of the water.
- Don’t swim or wade.
- Don’t drink the water and know it’s never safe to drink water from lakes or rivers.
- When boating, avoid the areas with the algae.
- Clean fish well with potable water, and discard the guts.
- Contact poison control at 1-800-222-1222, or a health care provider, if people or animals have symptoms.
More information, including guidance for managers or owners of waterbodies or owners of pets can be found at colorado.gov/cdphe/harmful-algae-blooms.
