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Dragonflies and monarchs: a two-generation migration

In the world of dragonfly and butterfly migration, it takes two generations to complete a round-trip. Adults migrate south in the fall and their offspring return north in the spring.

September 19, 2017
Butterflies migrate so they can have greater access to food.
Butterflies migrate so they can have greater access to food. © DUC/Claude Ponthieux

Butterfly migration

Monarchs are one of the most well known butterflies in North America—and butterfly migration is now quite well understood. Monarchs in Manitoba, for example, begin to move south in the late summer. These migrants make it all the way to Mexico where they spend the winter. In the early spring, they will begin to head north. They probably only make it to Texas, where they start a new generation and then die off. Adults born in Texas will then continue north to Canada. They migrate so that they can have greater access to the milkweed plant, which is necessary as food for their young. As they move north, there is also less competition for flower nectar.

Dragonflies migrate using natural landscape features to guide them.
Dragonflies migrate using natural landscape features to guide them. © DUC/Tye Gregg

Dragonfly migration

Unlike butterfly migration, dragonfly migration is less understood. Like Monarchs, they begin to travel south in late summer. The dragonflies migrate to warmer areas, near the Gulf of Mexico or south into Mexico. It’s believed they find their way south using natural landscape features, such as seacoasts and large rivers.

Dragonfly migration takes place in large swarms. In the swarm there is no actual leader, just many of the same insect traveling together.

One of the interesting features of dragonfly migration is that it seems to follow the passage of cold fronts. It has been noted that even in two separate geographic areas, two separate swarms of dragonflies began to migrate in response to the same cold front.

Much like the Monarch, the adults that head south in the fall will not be the same ones to return to Manitoba in the spring. It will be their offspring completing the trip.