The province has put up algae warning signs at two Manitoba beaches.
Its most recent advisory came Saturday morning, after an algal bloom was observed on Killarney Lake Beach during the week.
It said it tested the bloom on July 9, and the number of blue-green algae cells was above the recommended guideline.
There have also been algae advisories at the Ninette area of Pelican Lake since an algal bloom developed in late June.
Warm and calm weather increase the risk of blue-green algae developing.
The province is reminding people to stay out of any water with severe algal blooms and not let their pets drink it either. Blue-green algae can cause diarrhea, stomach cramps and eye and skin irritation.
The province has also posted swimmer's itch advisory signs at Moose Lake Provincial Park, Winnipeg Beach (Lake Winnipeg) and Gull Lake.