More Animals That Migrate: Who Knew?
By Marilyn Shy, Kalkaska Conservation District
During the winter months, amidst the piles of snow, we notice a few animals missing from the environment. Some are sleeping during the coldest days, emerging on sunny, warm days, and some are true hibernators. Other animals, such as hummingbirds, warblers and monarch butterflies are migrators, leaving the snow and cold behind for warmer climes.
But did you know that some dragonflies are also migrators??
I first learned this about a year ago while observing the monarch migration at a location in the UP called the Stonington Peninsula. This point of land juts into Lake Michigan and serves as a funnel for the monarch butterflies heading to Mexico. Indeed, if you drive along US-2 from St. Ignace westward, which parallels the northern coast of Lake Michigan in late August or early September and watch for monarchs, you may see them heading west towards Stonington.
While at Stonington my friend and I happened to observe great numbers of dragonflies, also roosting in small trees and bushes, waiting for the right wind to launch themselves and ride the northerly currents over the great expanse of water, taking them closer to their southerly goal.
From that day forward I made an effort to learn more about these small creatures that apparently travel on incredibly long journeys each year.
There is much that is still unknown about dragonfly migration, but it turns out there are at least 16 confirmed migrant species of dragonfly. Five are considered as the “main” migrants, while 11 others have been seen migrating at some places and at certain times.
What is known about the Common Green Darner dragonfly is that it is similar to the monarch butterfly in that more than one generation that completes the migratory loop. This means that dragonflies that leave here in the fall are not the same individuals that return in the spring. The first generation of Common Green Darners emerge from ponds in the southern United States, Mexico and the Caribbean in the spring. They travel hundreds of miles north, lay their eggs, and then die. The second generation of dragonflies, hatched out of ponds in the north, reach maturity and head south between July and October. They lay eggs in southern ponds to create a third generation. This third generation lives a non-migratory life. They produce eggs that hatch into the individuals that journey north in the spring.
How and why do they do this? More research is needed to answer these and many other questions.
Some fun facts that scientists have learned:
· The Wandering Glider dragonfly, also known as the Global Skimmer, is one of the longest distance travelers that we know of, estimated to travel 4,400 miles during migration.
· The Twelve-Spotted Skimmer has been seen migrating along the Atlantic Coast and turns up in the south by late summer. It also occurs in northern Michigan.
· Migratory dragonflies often use the same flyways as hawks and falcons. This is probably not a coincidence as hawks and falcons eat dragonflies, and so are likely following their prey as it moves south.
The Migratory Dragonfly Partnership uses reports from citizens to track the migration of dragonflies. You can add your sightings to the data or learn more about migrating dragonflies by going to: http://www.migratorydragonflypartnership.org. Plan to track your dragonfly sightings this summer at a pond near you!