Most smelt in northern Ontario are an invasive species and they're making lake trout smaller
New research is trying to determine how invasive smelt spread throughout the Great Lakes basin
Lake trout in some northern Ontario lakes aren't as big as they used to be, and a geneticist says it's because of another fish, you likely didn't know was an invasive species.
Christian Therrien, a researcher at the University of Waterloo, says new findings have shown that when lake trout consume rainbow smelt – which aren't native to northern Ontario lakes – it can lead to heart issues and thymine deficiency.
"I'll use Lake Wanapitei as an example. My grandfather is saying back in the day we used to catch huge Titanic lake trout, you know, five feet long. And now you have a hard time getting them over 24 inches," Therrien said.
"We are learning that in some instances rainbow smelt are having an affect on our native species. Some populations they don't seem affected, some they do. It's going to require more research to determine what the affects are province-wide."
Therrien says there is some evidence that there once was a native smelt population in northern Ontario, along the Ottawa River and up in the Lake Temiskaming area.
But he says most of what is now caught in creeks and rivers every spring is an invasive species, some which originate in the Gulf of St. Lawrence and the others that were introduced by humans into Crystal Lake in Michigan in 1912.
"They showed up in the upper Great Lakes by about the 1950s and then were spread thereafter," Therrien said.
Therrien said it would be nearly impossible to remove invasive smelt from the lakes in which they have spread over the last century.
But a team of researchers from the University of Waterloo is working to identify the different invasive smelt species in the region and find out exactly how they spread.
"We don't even really know exactly how they managed to invade it and spread throughout the province," Therrien said.
"So that's really the main goal of our project here is to determine how they got here, their spread and potentially be able to prevent invasive species invasions and their spread."
He said they are also working to educate anglers about smelt to ensure they aren't spread to new lakes.