Monarchs make the most of a mild summer, biologist says

There are more monarch butterflies in Ontario this summer, but University of Guelph population biologist Tyler Flockhart says that shouldn't stop people from reporting sightings, especially as the butterflies travel further north.

Guelph biologist Tyler Flockhart says the monarch population is on the rebound after a harsh winter

There are more monarch butterflies in Ontario this summer than the previous four summers, says University of Guelph population biologist Tyler Flockhart. But more work is needed to ensure they continue to thrive. That includes having people report sightings. (Matthew Beck/The Citris County Chronicle/Associated Press)

If you've noticed more monarch butterflies fluttering around your garden this year, you're not alone.

Tyler Flockhart has noticed the increase as well. The population biologist and researcher at the University of Guelph, said the butterflies are doing very well this summer thanks to average temperatures and rain conditions during their migration from Mexico.

It's great news considering a report in February that said the number of monarch butterflies wintering in Mexico had dropped by 27 per cent.

But while it's lovely to see one or two a day, Flockhart said that's still far from what we should be seeing.

"On the one hand, it's really nice to see monarch butterflies as you're out walking in your neighbourhood," he said. 

"But as a scientist, I think to myself, I need to be very cautious about this because we don't want to get ahead of ourselves and think that what we're seeing right now in southern Ontario is reflective of what's happening across the range."

University of Guelph researchers have led a study that pinpointed where monarch butterflies were born in North America. (KAP Design )

Need for reports of sightings

Monarchs are considered a species of "special concern" on Ontario, which means they're neither endangered or threatened right now, but they could be.

Flockhart said he wants to encourage people to document when they spot monarchs, because it will help track populations.

"This is the future for ecology, is having people making reports and then having that data available to scientists to actually tell us what is happening," he said, adding websites and apps like and eButterfly make it easy for people to record sightings.

"Scientists like myself, I use that type of information to understand what's happening with this population, because a handful of scientists cannot monitor a population that spreads across three countries."

How do butterflies get to Mexico?

7 years ago
Duration 2:11
The monarch butterfly is the only insect that migrates over such a vast distance

Concerns as monarchs head north

Tracking butterflies will also help scientists who are concerned about monarchs heading further and further north.

Flockhart said every summer, the butterflies move a bit further into Algonquin Park.

On June 13, one user on the website spotted a monarch in Gowganda, Ont., which is north of Sudbury.

Another user from Port Loring, Ont., west of Algonquin Park, reported seeing several butterflies in July.

A golf club in Pointe-Claire, Que., also said monarchs have returned this summer after they didn't spot a single one in 2016.

"With climate change, we expect butterflies and other insects to be moving north. And that happens every year," Flockhart said.

"The question is, as those butterflies go further north, they have a longer fall migration all the way to Mexico," he noted.

"Will those butterflies actually be able to make it, or are these going to be butterflies that are essentially lost from this population because they're moving so far north?"


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