The shorter days are a signal to Monarch butterflies to migrate south. Some travel more than 2,000 miles to winter in Mexico. (Photo by Marty Davis courtesy of Monarch Watch)
Right now, hundreds of millions of monarch butterflies are making an incredible journey south to Mexico for the winter. They’re flying through Michigan for the next couple of weeks so you have a really good chance of seeing one if you’re outside. Steve Malcolm is a professor of ecology at Western Michigan University and an expert on monarch butterflies.
Transcript
Professor Malcolm, how on earth do monarch butterflies find their all the way to Mexico?
Steve Malcolm, PhD: Um, that’s a good question, we’re not absolutely certain how they do it. It may be that the very fast rates of decreasing day length change trigger physiological changes that cause them to move to the south. But quite how they orientate to Mexico we’re not absolutely certain.
RW: And these butterflies are famous for covering thousands of miles as they’re going on this migration. Is it just one insect making this journey?
Steve Malcolm: In the autumn, the adults that have bred in the Great Lakes region, southern Canada, as they’re flying south will be exploiting nectar resources so they can really build up their fat so by the time they get to the Gulf Coast they’re these huge, obese butterflies. They continue their migration to Mexico and spend five, even six months in Mexico and then they fly north in the spring, and maybe get as far north as central states like Kansas or even Iowa. Then they’ll basically die and it’ll be their offspring that continue the migration back to the Great Lakes region.
RW: There are some butterflies that look like monarch butterflies. How can you tell them apart?
Steve Malcolm: In the Great Lakes region, the viceroy is the only butterfly that looks very like a monarch. But the monarch has this typically lazy flight. It’s sort of a bold butterfly, you know, it just flies around and does its own thing. The viceroy it’s got the same basic coloration of being orange with black wing veins, but it has a more flick-y flight, it looks like a more nervous butterfly. It’s a little bit smaller than a monarch. If you look at it end on, it looks very flat somehow. Monarchs tend to look more like a flapping V if you like when they’re flying around in the environment.
RW: Where are the best places in Michigan to go if you want to see monarchs heading south?
Steve Malcolm: I personally like going to the Wickham music festival which was on this last weekend in the middle of Michigan, and lying on my back listening to the music watching the monarchs flying overhead. Typically you can lie there and watch a monarch flying over every minute. But also going to the shores of Lake Michigan is very good. Anywhere on the west side of Michigan, along Lake Michigan, if you walk on any of the beaches there you can usually see monarchs. They’ll arrive at the water’s edge and then they’ll pretty much fly south down the lakeshore.
RW: What can we do to help the butterflies out?
Steve Malcolm: I think it’s really good to do some butterfly gardening, particularly this time of year, to have nectar plants. It’s really helpful for the butterflies to have lots of food resources so they can build up their fat. Having a patch of milkweed, like common milkweed, or butterfly weed or the swamp milkweed. But I think it’s important to make sure they’re native milkweeds that belong in Michigan rather than some of the exotic milkweeds that are easy to grow.
RW: Well, thank you so much for your time.
Steve Malcolm: You’re very welcome.
RW: Steve Malcolm is a monarch butterfly expert at Western Michigan University.
That’s the Environment Report. I’m Rebecca Williams.