In February the dragonflies appear only in warm latitudes, which is reflected in data showing dragonfly emergences at this time in Florida, Louisiana and Texas, as well as Puerto Rico, Cuba and southern Mexico. But come March, this first generation has already winged it up to the American Northeast, the Great Lakes region and southern Canada. And then those well-traveled dragonflies mate, lay eggs and die.

In May and June, the second generation hatches onto the scene. Some live their whole lives locally, but others — driven by what, we do not know — point their beautiful compound eyes south. Between September and November, these snowbirds don floral shirts and sunglasses and can be found flitting around the southern U.S. and Caribbean. Like the first generation, these dragonflies mate, lay eggs and die.

This leaves us with the third generation in the cycle, which are the population's homebodies. Because winter hits the south soon after they hatch, and they definitely don't want to head north to even colder climes, these lucky darners live out their life span locally. And then they ... mate, lay eggs and die like the rest. Their offspring then hatch around February, transform from larvae to adults, and head up north, starting the cycle anew.

The great dragonfly migration has likely been taking place for many millennia. Each generation has a job to do and an itinerary to follow, and every step is tied to a specific temperature range.

"So one of the things that we figured out from the citizen science data of over 20 years across the whole eastern United States is that the dragonflies don't begin migrating until it gets to about 9.5 degrees Celsius, or just shy of 50 degrees Fahrenheit," said Studds. "They kind of wait for it to go up to that point and they follow that temperature north."

Enter climate change. Temperature patterns are shifting all over the U.S. (indeed, the whole planet), and research on monarchs is already showing that such fluctuations may affect how the butterflies inoculate themselves against parasites. Could there be similar consequences for other migratory insects?

"If we are moving into a period where winter temperatures are warming and spring temperatures are getting warmer through time, then that will probably affect the entire timing and pace of dragonfly migration," said Studds. "It will affect how far north they go and how quickly they develop."

In some areas, warmer temperatures year-round may mean dragonflies won't even need to migrate at all. This isn't necessarily bad for the darners, mind you. But because dragonflies are important predators of mosquitoes, aphids, and other insects, as well as nutritious food for ducks, toads, newts, fish and even carnivorous plants like sundew, losing a seasonal influx of these creatures could ripple out through North America's ecosystems. (Plus, dragonflies are beautiful, and people up north will miss them.)

The truth is, scientists still know very little about how these seasonal shake-ups will affect wildlife, and common green darners and monarch butterflies are just two species among many that are facing big changes. But given that insects are experiencing dramatic declines worldwide, we need to unpack as many of these little mysteries as we can now — instead of trying to piece the puzzle back together after it's too late.