The compound eyes of a sedge darner dragonfly. Each eye is made up of thousands of light-and-motion sensitive units. (Courtesy photo | Ned Rozell)

The compound eyes of a sedge darner dragonfly. Each eye is made up of thousands of light-and-motion sensitive units. (Courtesy photo | Ned Rozell)

Dragons of summer now on the hunt

They’re basically bush pilots.

The Piper Super Cub is a nimble favorite of Alaska bush pilots who land on and take off from gravel bars and mountaintops. Engineers who designed the plane in the 1940s found a simple model that still works.

Another flying machine, the dragonfly, has not changed much in 300 million years, except it is no longer as large as a raven.

Humans have for a long time admired the design of this creature, one that can fly backwards and zigzag with abrupt turns.

Aerospace scientists at the University of Colorado once leashed live dragonflies inside a wind tunnel. By observing smoke added to the wind, the researchers noticed the dragonflies twisted their wings on each downstroke. The smoke curled off the top of their wings, reducing air pressure there and providing more lift than is available to any aircraft with static wings.

Closeup of a dragonfly wing. (Courtesy photo | Ned Rozell)

Closeup of a dragonfly wing. (Courtesy photo | Ned Rozell)

A few years ago, scientists at Harvard, the University of Chicago and Columbia developed a mathematical model in an attempt to predict and duplicate the complex patterns within dragonfly wings.

Each veined dragonfly wing, “a model of evolution and biological engineering,” is as unique as a human fingerprint, wrote Harvard Ph.D. student Jordan Hoffmann, a mathematician who likes to find order in systems that seem to have none. His team came pretty close to nature’s design.

Worldwide, there are about 3,000 species of dragonfly. Thirty types live in Alaska. The largest in the state is the lake darner, a cool blue dragonfly that turns dark when the air is chilly. The delicate treeline emerald flies around cold ponds north of the Brooks Range, miles farther north than any tree. The azure darner patrols the extreme northern coast of Alaska, just a few yards from sea ice and the Arctic Ocean.

The dragons of summer live as flying adults in Alaska for about two warm months. They can live much longer as larvae in bodies of water. After hatching from an egg and developing into an aquatic creature, the larvae use a spoonlike lower lip to capture small fish, tadpoles and other insects. Larvae then crawl above the water on the stems of aquatic vegetation, shed their larval skins, and pop their new wings out to dry.

Often pursuing moths, midges and mosquitoes from beneath, dragonflies succeed at catching their prey about 95 percent of the time. This is according to Harvard researchers who in 2011 documented dragonflies’ efficiency at capturing fruit flies.

A dragonfly larva, with ladle lip extended, collected by UAF Bug Camp participant Finn Lindsey in 2016. (Courtesy photo | Ned Rozell)

A dragonfly larva, with ladle lip extended, collected by UAF Bug Camp participant Finn Lindsey in 2016. (Courtesy photo | Ned Rozell)

Dragonflies have such a short time to shine here in Alaska because, like most insects, they need warm air temperatures for their body parts to perform. Biologists Pat Doak and Todd Sformo studied dragonflies on the UAF campus in Fairbanks. They found the adults started flying when the air temperature warmed to 57 degrees Fahrenheit.

Forty-eight states have official insects. The dragonfly took the honor in both Alaska and Washington. Butterflies are the official insect of most other states.

Alaska school kids voted for a state insect during the 1993-1994 school year. The four-spotted skimmer dragonfly took first, over the second-place mosquito. Rep. Irene Nicholia, who sponsored the bill, explained.

“The dragonfly’s ability to hover and fly forward and backward reminds us of the skillful maneuvering of the bush pilots in Alaska,” she wrote.


• Since the late 1970s, the University of Alaska Fairbanks’ Geophysical Institute has provided this column free in cooperation with the UAF research community. Ned Rozell ned.rozell@alaska.edu is a science writer for the Geophysical Institute.


More in News

A Princess Cruise Line ship is docked in Juneau on Aug. 25, 2021. (Michael Lockett / Juneau Empire File)
Ships in Port for the week of May 22, 2022

Here’s what to expect this week.

Coast Guard aircrews medevaced two people from Dry Bay Airstrip, approximately 30 miles Southeast of Yakutat, Alaska, after their plane crashed, May 25, 2022. (Courtesy photo / Coast Guard District 17)
Three medevaced after plane crash near Yakutat

All four aboard were injured, three critically so.

The author’s appreciation for steelhead has turned into something like reverence considering what’s happening to populations in the Lower 48 and Canada. (Jeff Lund / For the Juneau Empire)
I Went to the Woods: Silent steel

“You forget most of what ends up in the freezer, but those steelhead, they stick with you.”

Senate President Peter Micciche, R-Soldotna, seen here in this June 16, 2021, file photo, announced Wednesday he will not seek relelection in the Alaska State Senate, where he has served since 2013. (Peter Segall / Juneau Empire file)
Senate president says he won’t run again

“Honor and a privilege.”

Hoonah’s Alaska Youth Stewards helped make improvements to Moby and water the plants in summer 2021. (Courtesy Photo / Jillian Schuyler)
Resilient Peoples & Place: Moby the Mobile Greenhouse cultivates community

It presents opportunities to grow food knowledge and skills.

It's a police car until you look closely and see the details don't quite match. (Juneau Empire File / Michael Penn)
Police calls for Thursday, May 26, 2022

This report contains public information from law enforcement and public safety agencies.

Gavel (Courtesy photo)
Alaska Supreme Court orders use of interim map for elections

The decision came just over a week before the June 1 filing deadline for the August primaries.

Most Read