An early-season blue-green algae alert has shut down much activity on Pine Lake because of the potential for illness and even death, and according to one expert, better lakeshore protection is needed instead of development.
A week ago, Alberta Health Services issued a blue-green algae advisory for the lake east of Innisfail.
David Schindler, a University of Alberta biology professor, said shallow Alberta lakes are very susceptible to these alerts and the occurrences do pre-date development.
However, he said humans do a lot to exacerbate the increase of phosphorus into the lakes, which causes blue-green algae blooms to occur more frequently.
“Septic tanks, land clearing for cottages and agriculture, fertilizing fields, lawns and gardens, pet excrement all cause increased inputs, especially of phosphorus,” wrote Schindler in an email to the Advocate.
“Our studies show that most lakes in Central Alberta have increased two-to-three-fold in phosphorus inputs since the mid-20th century.
“The key to preventing blue-green algae involves better management of the phosphorus entering the lake.
“Society is too weak-willed to deal with the problem. Less development, less use of fertilizer, more protection of lakeshores are what we need.
“People ignore this need, and are continually sold ‘magic bullet’ solutions like bubblers, copper sulfate, compounds to lock phosphorus in sediments, etc. Some of these have a short-term effect, but none is a long-term solution, being overwhelmed by development,” said Schindler.
“At 74, having spent my life determining how to control these blooms but everyone simply ignoring the evidence and continuing to destroy our lakes, I am very sad.”
Lakes in Alberta are monitored by summer students working as public health inspectors, under the supervision of professional inspectors.
The students take samples from the lake for cell and microcystins, one of the toxins, and also observe the lake.
Dr. Digby Horne, AHS Central Zone medical officer of health, said these advisories happen every year in certain lakes, but are pretty unpredictable.
Pine Lake has had a blue-green algae advisory for many years, including consecutively since 2011.
The alerts typically come later in the summer.
“Often the recommendation is made on visual evidence of a bloom because it can sometimes take a while for the microcystin toxic levels and algae cell counts to be determined,” said Horne.
“If they see a bloom, then they post an advisory at the lake right away.”
A 2012 study published by 16 scientists in the Canadian Journal of Fisheries and Aquatic Science found the highest concentration of microcystins in many Albertan lakes, including Pine Lake.
Blue-green algae can be fueled by sunlight, higher temperature, nutrient loading to the lake or even water turbulence.
“The algae can make themselves more or less buoyant and they can do that in relationship to turbulence in the water,” said Horne.
Horne said blue-green algae can also be fuelled by fertilizers from land adjacent to the lake getting washed into the lake by rain.
“You provide more nutrients to blue-green algae, when conditions are right,” said Horne.
The toxins can still exist after the bloom has disappeared from site.
Horne said there are neuro and liver toxins.
“If you were to get enough of a neuro toxin or liver toxin, this happens with animals sometimes, you can get death within several days,” said Horne.
It would take a significant amount of exposure, either through contact or ingestion, for death to occur, but it is still a possibility. Horne said age would be a factor as young and elderly people may have reduced ability to fend off toxic effects.
“The advisory could be on for some time, right up to November,” said Horne, adding cooler temperatures can help alleviate the issue.
As part of the warning, people are advised to not drink the water; not swim or wade; avoid contact with algae along the shoreline; do not feed whole fish or fish trimmings from this lake to pets and limit consumption of whole fish and fish trimmings from the lake.
Fish fillets can be safely consumed.
People who come into contact with or ingest the water may experience skin irritation, rash, sore throat, sore red eyes, swollen lips, fever, nausea and vomiting and/or diarrhea.
Anyone who suspects a blue-green algae problem, or if you require more information, call Health Link Alberta at 1-866-408-5465.