The Luna Moth is Driven by Pure Romance

Apr 1, 2018

Step outside this week and discover nature in a six-legged winged symbol of love.

This week is the luna moth’s one-week life on the wing as he’s driven by pure romance. Not exclusive to Missouri, or even the Midwest states, the luna moth can be found from east of the Great Plains in the United States, to northern Mexico and from Ontario eastward through central Quebec to Nova Scotia in Canada.

The caterpillars feed on birch, alder, persimmon, sweet gum, hickory, walnut and sumac trees. However, once they reach adulthood, these members of the silk-moth family have no mouths and are undistracted by hunger or thirst as the males follow invisible trails of pheromone molecules to find stationary females. As adults, their inability to eat also limits their life span, which means these moths must work to find each other quickly.

Mating will take place late in the evening after midnight and egg-laying will begin that evening. Clutches of 100 to 300 eggs take about 10 days to hatch and afterwards the green caterpillars spend two months eating leaves of hardwood trees before spinning silken cocoons, where they turn into brown, hard-shelled pupae that take two weeks to form into adults.

The adult moths emerge from their cocoons in the morning. Their wings are very small until they work to enlarge them by pumping bodily fluids through them. During this time, their wings are soft and they must climb somewhere safe to wait for about 2 hours for their wings to harden before they can fly away. They emerge as adults solely to mate, living only one week.

Adult luna moths are very strong fliers and are easily identified by their pale green wings, each with one transparent eyespot and an outer pink margin. Their hind wings have long curving tails.

Since they’re attracted to lights, your front porch may be a good place to catch them taking a rest this week.

To keep track of current natural events like when to watch for the flight of luna moths, you can get your own Natural Events Calendar from the Missouri Department of Conservation.