I am saddened to advise you that a major fish kill occurred at Stoney Lake (in the St. Paul area) this past week.
Large numbers of Yellow Perch of all age classes including perch in the 30 cm (12 inch) size, pike and burbot were found on the shore, on the lakebed, and floating in the lake. The presence of blue-green algae was noticeable earlier in the week and after two cloudy days the algae died. The rapid decay by bacteria caused the dissolved oxygen in the water to decline to levels that were too low for fish to survive. The result was low oxygen for a few hours and that was enough to kill fish. The water looks very clear after these events with little blue-green algae present.
The fish counts in some areas averaged 60 perch per metre of shore (see photos). Less pike and burbot were observed.
Stoney Lake has been an excellent winter and summer fishery for the past few years with large numbers of people harvesting large numbers of fish and major disappointments from anglers is to be expected. At this time it is not known if all the fish died; however, seeing large numbers of young small perch suggests quite a significant kill as usually small-sized fish are able to survive lower oxygen better than large-sized fish.
Fish habitat protection is the most important factor in managing fish resources. Anything that can be done to reduce nutrients (fertilizers, garbage, sewage, eroding soils and sediment) must be done to ensure that the fish habitat is not harmed.
Come to the meeting at Lac Bellevue Hall on September 7, 2016 at 7pm for further discussions on managing fish resources in Alberta. – Ray”