Exquisite nature
In our second summer at Marquette, I was in the yard when a bright blue bug with large transparent wings flew by me to catch a smaller bug on our windowsill (dinner!). Wow, I discovered that we have Damselflies at Marquette! I was familiar with them because they were found in the yard of our previous house along the banks of White River.
Over the next few months, I took my camera and telephoto lens to Marquette’s ponds and Crooked Creek to photograph Damselflies and Dragonflies. These are beautifully colored, ancient insects that inhabit our ponds, creeks and woods in Indiana. They don’t bite or sting. They are beneficial because they can consume their weight in mosquitoes in a few hours.
The flies are 1 to 2 inches in length and width (with wings extended). They don’t efficiently regulate their body heat, so they warm up by sunning themselves on pond rocks or the bridges over Crooked Creek. They are best viewed after noon with low power binoculars. The two suborders in the ancient order of Odonata are easily differentiated. Damselflies hold their transparent wings along their thin 1 to 2-inch body when perched. Dragonflies hold their more colorful wings out perpendicular to their body when perched. The individual species are clearly identified by color patterns of their head, eyes, thorax and abdomen using one of the excellent Odonata guidebooks or phone apps.
We have a long and distinguished history of Damselfly and Dragonfly research in Indiana. Thomas Say of the Robert Owen Utopian Community in New Harmony published drawings and accounts of Odonata in his ‘Descriptions of Insects in North America,’ 1824-1828. Basil Ellwood Montgomery (1899-1983) was a leading expert on naming of Dragonflies at Purdue University. His collection of papers and 20,000 specimens is at the Smithsonian Institution in Washington, D.C.
In late May, the flies are just emerging from their larval (also called naiad or nymph) stage in our ponds and creek. They undergo a miraculous metamorphosis underneath their exoskeleton before they emerge as flying adults. They cease using gills to extract air from the water in the larval stage and form a tube-like respiratory system to directly extract air in the flying adult. They form wings to achieve helicopter-like flying in all directions. They have large compound eyes that facilitate efficiently hunting of mosquitoes in flight.
In June through August, the Damselfly and Dragonfly males will be looking for mates. The whole purpose for morphing to the colorful flying adult is to reproduce the species. Males will lock onto a process behind the head of a female with a hook at the end of their abdomen. This is the ‘tandem’ position, and they can be seen flying together. The male and female then form a wheel or heart-shaped structure when they fertilize eggs. The female lays her eggs in the water where they hatch. In October, the weather gets so cold at night that the flying adults die. The larva stay in the water for one or more seasons to feed, grow and molt. They emerge in May and the cycle starts all over again.
Contributed by: Bill Bosron
