Algae blooms are often found on Saskatchewan's lakes
during a period of warm, calm weather
Every year during the warm summer months many Saskatchewan lakes may suddenly take on a soupy appearance. The water surface becomes blue-green, bright blue, grey or tan in color. The organisms responsible for these changes are microscopic plants called algae or phytoplankton. When algae grows so thick it makes the water look like pea soup, it's called an algae bloom.
People are advised to avoid swimming in, or drinking water, where blue-green algae blooms are occurring. Pet owners and livestock producers are also advised to keep their animals away from such water.
Algal blooms commonly occur during calm, hot weather in areas of lakes and reservoirs where the water is slow moving and rich in nutrients.
An algal bloom can last as long as two or three weeks and may actually be pushed around the lake or reservoir by the wind.
Murray Hilderman of Saskatchewan Environment says dying and decomposing alga occasionally reduce the oxygen level in shallow water bodies so much that it sometimes kills fish.
"Because these factors vary from year to year and from one lake to another, it is difficult to predict when an algal bloom will occur, except to say that they are more prevalent from June to mid September," says Environment's Hilderman.
"Unfortunately, this coincides with our most active season for outdoor recreation and, because floating or shoreline algal masses aren't nice to look at, people often complain about the
appearance and color of the water during summer months."
Environment's Hilderman also says although many types of harmless algae can create blooms, blue-green algae are of greater concern because they can be toxic.
"Blue-green algae contains toxins which can be released into the water when the cells are stressed, rupture or die," explains Environment's Hilderman. "When ingested in large quantities these toxins are powerful enough to kill livestock and pets. Humans may also be affected by swimming in blue-green algae. Possible symptoms in humans include skin reactions,
sore throat, nausea, cramps, vomiting and diarrhea. In addition, caution should be taken when considering the consumption of fish or shellfish caught in areas of a water body where a bloom exists; in particular the internalorgans of the fish should not be eaten."
Environment's Hilderman says without a microscope it's hard to tell whether the algae is blue-green or a harmless type, so people should avoid areas of a lake that have an algae bloom. Children should be supervised to make sure they don't drink the water and alternative water sources should be provided for livestock and pets.
If someone is looking for more information about algae or algae blooms they can contact any Saskatchewan Environment office or the local Medical Health Officer.
For more information contact;
Murray Hilderman
Environmental Sciences Section
Saskatchewan Environment
(306) 787-6181
mhilderman@serm.gov.sk.ca
Or
Art Jones
Communications Consultant
Saskatchewan Environment
(306) 787-5796
(306) 536-8452 (cell)
ajones@serm.gov.sk.ca
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