Return to the Wild - Evolving perspectives on Canadian wildlife
The monarch butterfly has been recorded in all of Canada's ten provinces.

Did you know?

The monarch possibly has the longest insect migration in North America, travelling up to 4,000 kilometres a year.

Scientific name: Danaus plexippus
Average weight: 1.5 g (caterpillar)
0.4 g (butterfly)
Average wingspan: 93–105 mm
Average lifespan: 6–8 weeks (summer generation)
6–8 months (winter generation)
A monarch butterfly perches on top of a flower.

Canadian Geographic articles

Winged wonder

By Dane Lanken
May/June 1993

Though a common presence in meadows and parks through the summer, the monarch butterfly is still a constant source of fascination for everyone from accomplished entomologists to backyard naturalists, and as writer Dane Lanken discovers, the colourful insect has a life cycle that is as complex and fascinating as an animal 10 times its size.

The life cycle begins with a miniscule egg inconspicuously laid on a milkweed. The larva, which grows into the recognizable black, white and yellow caterpillar we are so familiar with will eventually form a chrysalis and become the flashy adult that frequents garden flowers all summer.

But what happens to the butterflies during the winter? To find out, Lanken has made this article in part a profile of pioneering entomologist Fred Urquhart. Taking a page from reseachers who were tracking migratory birds, Urquhart began to tag butterflies in the 1950s.

Placing stickers on the wings of butterflies that said, “Return to the Museum of Zoology, Toronto, Ontario”, Urquhart eventually developed a network of naturalists that helped determine the path of the butterflies throughout Canada, the United States and Mexico, but it wasn’t until the 1970s that the final destination of the enigmatic little insects was revealed — a mountainous area west of Mexico City.

Mapping migrations

By Candace Savage
September/October 1999

Though we’ve known where the monarchs go for many years, it’s only recently that it has been possible to figure out where the monarchs come from.

Previously, the butterflies were tracked using stickers; a particular sticker indicated where the monarch had originated its migration south. Unfortunately, the results from this type of tracking were minimal, and only hundreds of butterflies were identified, as opposed to the millions that congregate in the mountains of Mexico each winter.

However, chemical analysis of dead butterflies collected at the wintering site has helped to solve this problem. Scientists Len Wassenaar and Keith Hobson, of the National Water Research Institute and the Canadian Wildlife Service respectively, developed a technique that now allows researchers to estimate the origins of the nomadic butterfly.

Minute chemical differences — which have their origin in the water that is consumed by the insects — in their physical makeup are particular to the region, province or state that the caterpillars hatched in. And even more interesting, this type of analysis is not just for butterflies.

If you do not have Acrobat Reader®, please click on the following link Adobe Reader to download it from the Adobe® Web site.