A growing number of lakes in Manitoba are showing signs of stress, prompting residents to ask if it’s time to start taking their water seriously.
The latest report from the Canadian Centre for Policy Alternatives and the University of Manitoba found Lake Ontario in the province’s northwest region had a “significantly elevated” concentration of microfilariae — microscopic algae found in lakes and rivers.
About 5,000 microfilters were found in one lake and more than 1,300 in another, according to the report.
Lake Ontario has about 1,200 of them, the report found.
The most worrisome concentrations of microfilters are found in Lake Superior and Lake Erie.
They’re more common in rivers, lakes and streams than lakes.
Microfilters can be found in almost any waterbody, from the surface of a lake to the bottom of the lake.
The problem is they can grow at a rate of more than 5 per cent a year.
The Canadian Centre For Policy Alternative, which has been tracking microfiltration in lakes in North America, estimates that the problem could be worse in Manitoba, which is also suffering from an abundance of fish.
Lake Superior, for example, has more than 100,000 fish that have died from microfiler infections, compared to Lake Erie, where about 1 per cent of fish have died.
But Lake Superior has the advantage of being far more remote, so it’s more difficult to test for microfiltrates, said Scott Kavanagh, a microbiologist and co-author of the report from The Canadian Center For Policy Action.
Kavanah said the lakes are in better shape now than when the problems first emerged in the late 1990s.
Lake Huron, Lake Ontario and Lake Ontario Harbour in Manitoba.
(CBC)Microfilter infections are more common on lakes and in lakes that have experienced floods, said Michael Hernández, a professor at the University at Buffalo.
The main problem is that we’re not very good at predicting what microfiling might be like in different parts of the world, he said.
He noted that some lakes have been identified as “hotspots” for microfiled organisms, while others have been overlooked by experts.
Microfiling is most prevalent in the north, in the northwest, and in places like northern Ontario, said Hernàndez.
“The most likely reason is that the lakes that are most stressed in Manitoba have not been identified and there’s not enough testing for microfilm to really know how widespread this is,” he said in an interview.
“It’s a mystery to us.
We’re trying to find out what the real issue is.”
Hernáldez said it’s important to understand how much microfiltering can cause a problem.
The bigger the lake, the more susceptible it is, said Mark Ritchie, the co-director of the Lake Hurons Centre for the Study of Microfiltration at the UBC Institute of Aquatic Sciences.
Microfilm contamination of freshwater systems in lakes can cause algae blooms, which can damage fish populations, said Ritchie.
“Microfiltrating water can affect fish populations.
It’s not just a problem in one part of the province, it’s a problem across the province,” he told CBC News.
Hernòndez said microfilter contamination can affect the fish in lakes up to two metres deep, which are often the most sensitive species.
Microflora in lakes “is not just something that we can just treat, but it’s something that’s a concern,” he added.
Microfilters also can affect a lake’s ecosystem, said David Ducharme, a scientist at the Ecole Normale Supérieure des Sciences Laval.
“If a microfilm is present in a lake, then that means it’s affecting the ecosystem of that lake,” he explained.
“And that is an important concern because if you’re going to develop new fish habitat or if you want to move some of those fish to other lakes, then it’s going to impact all of those organisms.”
Lake Ontario, where microfiltered water is more common.
(Lake Ontario Harbour.)
“If you look at the numbers, microfilm concentrations in lakes are a bit lower than they are in other places,” said Ducharese.
“We know that microfilting is an issue because it’s associated with higher fish populations.”
Hernayes and Ritchie have been working to understand the impact of microfilm contamination in the Lake Ontario area.
The Centre for Biogeochemistry and Hydrology, a government agency, and the UB School of Fisheries and Aquatic Science are both working to figure out how much of a problem microfilming is.
Both groups are trying to identify the locations where microfilm might be occurring.
“Our hope is that this will provide a way to monitor microfiltration at a deeper level,” said Ritzer.