A drop in monarch butterfly population in the south could mean less to watch in Point Pelee

A new report says monarch butterfly populationsin Mexicohave decreased, but according to one expert, the number of butterflies Canada will see this year depends on whathappens this monthas they embark ontheir migrations north.

The presenceof the monarch butterflyin theMexican hibernation forestsdeclined by 26 per centdue to a reduction of its habitat,according to therecent report byWWF-Telmex Telcel Foundation.

According to the report, the speciesoccupied2.1hectares in December 2020 compared to the 2.83 hectares in December 2019.

These numbers are unsurprisingto Chip Taylor, thedirector of Monarch Watchat the University of Kansas.

"They were about as I expected," he said. "But that tells us that we are dealing with a population that fluctuates with the weather conditions, but it's also dependent on the amount of habitat available. Had there been a lot more habitat available last year in the form of nectar plants, then it's likely we would have seen a higher population," he said.

Taylorsaidthat monarchs need nectar plants andmilkweed, which he said Canada provides a lot of.

"As we get into Canada ... we get a lot more common milkweed. And one of the things that happens in Canada is that the monarchs who have reached Canada in May and June develop a population of common milkweed andthat population tends to move along the lakes and eventually move through Point Peleein fairly large numbers," he explains.

Everyfall, Point Pelee plays host to thousands of monarchbutterflies on their migrations. The insects make their way across Lake Erieto the mountains of Mexico, roughly 3,000 kilometres south, for the winter.

In late spring, their offspring return to Canada, and the cycle continues. According to Parks Canada, monarchs have a life span of about a month but the ones who emerge latein the summer are born to migrate and stay alive for oversix months to make the journey.

Taylor said it's hard to predict what the population of the monarch butterfly will be like this spring until he sees how conditions are like in Texas.

"The Canadian situation is highly dependent on what happens in March in Texas. Soif the returning butterflies are abundant and they have good conditions in Texas, there are good conditions as they move north in May and June and they encounter good conditions in Canada, the population does well," he said.

If they get off to a bad start in Texas. It's going to be a bad year in Canada.- Chip Taylor, director of Monarch Watch

Taylor said the butterflies have already left the overwintering sites in Mexico and should reach Texas in about two weeks.

"The question is, what are they going to find when they get there?" He asks, pointing to the massive winterfreeze that took place just weeks ago.

"The question I'm asking all my colleagues in Texas is that vegetation going to come back in time, sothey're going to be milkweeds above ground and nectar plants for the butterflies to feed on," he said.

Taylor said he's watching the weather and monitoringplant development carefully and can better predict how things will look in two weeks.

"What we've learned in the past is that what happens in March in Texas has a big influence that that determines everything that happens, including what happens in Canada,onthe rest of the year," he said.

"So it's very important for the population to get off to a good start. If they don't, if the population doesn't get off to a good start, then it's very likely that it's never going to be able to recover. There just aren't enough generations," he said.

What you can do

Taylor says people can help preserve the monarch butterfly by creating a lot of habitat for the species.

Point Pelee National Park also encourages local residents to plant a butterfly garden with native plants, milkweed for monarch butterflies and caterpillars.

"Create a habitat and they will come, they will use it," Taylor said.