A surprising number of fish have washed up on the shores of Pelican Lake, much to the shock of local anglers and Ninette-area cottage owners.
"There were upwards of about 1000 fish predominantly on the lake's south end where its more shallower, and definitely a lot warmer; less water to turn over and less places for the fish to go to get out of the heat," shares Healthy Lake Committee Chair, Trevor Maguire.
Maguire says there are a few factors that have contributed to the fish kill. With high water levels in spring, Pelican Lake received a lot of run-off at the start of the season, and with new water comes more nutrients, increasing the potential for blue-green algae blooms, the cyanobacteria toxins stressing the fish. Their beach was closed down during certain times in August due to recurring algal blooms. "It's always in all the lakes, but it's only when the water gets to these temperatures and the nutrients are high, you get these blooms that take over," he adds.
In addition, the recent heat wave with little wind warms water faster in a shallow lake like Pelican.
"The water temperature is above 28C and that really stresses the fish, particularly the larger ones," he explains. "In the south end particularly, it is a little shallower and we don't have an aeration system down there so there's no mixing going on so the fish stay in the hot water and eventually they don't make it."
Carp and suckers are getting hit the hardest, but walleye, northern pike and even perch have been seen washed up on shore as well.
"All species are getting clipped," notes Maguire, "unless they're moving away to deeper water or moving around the aeration systems where the water is cooler. The first 4 feet of the water is like bath-water."
With cooler night time temperatures, and the addition of wind and rain showers, the fish kill should be pretty much over, says Maguire.
"Night time temperatures are now dropping down into the low double-digits, high single-digits, so that's cooling the water off. That will make a huge difference. We had a little bit of rain the other day, and some wind will mix the water up and even the temperatures out, so the worst of it should be over," he adds.
Clean-up has its own set of challenges. Cottagers have been collecting the dead fish on their own waterfront. But bringing the dead fish to the landfill comes with immediate action as the fish need to be buried shortly after they've arrived... especially in these temperatures.
Having installed the two aeration fields a dozen years ago, Pelican Lake hasn't seen any serious fish die-offs like this for a long time. However, Maguire shares that this isn't a new problem for the lake. Prior to aerating, this was a more common occurrence.
"The difference right now is we've never seen Pelican Lake with this many fish in it, and as a function of aeration over the years the populations in the lake are anywhere from 4 to 6 times the normal peaks! So, with that many fish and then you get a die-off, you're just going to have more fish dead. The same problem with the outlet channel and the inlet channel, every time we open them they're now plugged full of fish, and everyone is kind of mystified. 'This has never happened before!' ... well we've never had this many fish before!"
"The one thing it does show you is that, in Pelican Lake, if we can keep the fish alive, it's an incredibly productive lake!" he adds.