Will the monarchs continue to travel north until they reach the arctic? What do you think? Why? Before reading the comments below from monarch expert Don Davis, discuss this question with your class. What do you think limits the distribution of monarchs? How far north do you think they'll travel?
Don Davis of Toronto, Ontario, CANADA, has tagged monarch butterflies for many years in order to study their migration. Here he responds to our question about the northern range of monarchs. Following his description, see if you can draw the monarch's range on a map of Canada:
"Dear Students,
"To answer your question of how far north the monarch butterfly travels--- there appear to be a number of factors involved, including the availability of milkweed, local climate, geographic conditions, and weather (i.e. strong winds).
"In the Province of Ontario, as mining and logging roads were built and as towns and villages followed, the range of milkweed (A. syriaca) expanded northward, followed by a range expansion by the monarch. At present, the northern range of the monarch butterfly in Ontario appears to be a line from east to west across the province which follows our most northern major highway--The Trans Canada Highway (both northern and southern routes, #17 and #11) through Kirkland Lake, Kapuskasing, Hearst, Geraldton, Dryden, and Kenore. The area north of the Trans Canada Highway is sparsely inhabited and consists of dense, rugged forest and terrain. However, monarchs have strayed as far north as James Bay!
"As for the prairie provinces of Alberta, Saskatchewan and Manitoba, monarch butterflies can be found in the southern regions of these provinces. However, individuals have either migrated or strayed to the central parts of these provinces too, and as far north, for example as Hinton, Alberta and The Pas, Manitoba. In Manitoba, monarchs are regularly found in Riding Mountain National Park, where milkweed grows. Monarch butterflies are extremely rare for mountainous British Columbia.
"Monarchs are also found in Quebec and in the Maritime Provinces. Apparently monarchs are not native in Newfoundland, as milkweed does not grow there. However, each year, a number of strays are found, possibly blown off course by strong winds.
"The most recent international range expansion of the monarch butterfly that I know of is a colony that has established itself in southern Spain! Monarch butterflies are not native to Great Britain and Ireland, but individuals are found in the south each year. These may have been blown there by strong winds from the Azores, Maderia or the Canary Islands. In Great Britain, I believe the monarch is also called the "Wanderer".
"Hope that answers your question!
Don Davis
Journey North 125 North First Street Minneapolis, Minnesota 55401 Phone: (612)339-6959