Luna Moth

Habitat

Luna moths inhabit hardwood forests across the eastern half of North America, from southern Canada to central Florida and west to the Great Plains. Caterpillars feed on the leaves of birch, hickory, walnut, sweetgum, persimmon, and several other hardwoods. Adults are nocturnal and short-lived, drawn to porch lights and other point sources from late spring through summer.

Behavior

The luna's whole adult life is a courtship sprint. After emerging from its cocoon, an adult lives only about a week — it has no mouth and cannot eat. Females release pheromones at night that males detect with their feathery antennae from over a mile downwind. After mating, females lay 200–400 eggs on host-tree leaves and then both adults die. The long, twisting tail streamers are an anti-predator adaptation: bat sonar locks onto the spinning tails rather than the moth's body, and the moth escapes while the bat takes a mouthful of wing tip.

Marginalia

• Adult luna moths have no functional mouthparts. They live entirely on the fat reserves built up as caterpillars and die within a week of emerging from the cocoon.
• The long, spinning hindwing tails are an active anti-bat defense — they confuse bat echolocation, so the bat strikes the trailing tails instead of the moth's body.
• Males detect female pheromones at distances over a mile with their elaborate, comb-like antennae.
• Luna moths were once common at porch lights across the eastern United States; populations have measurably declined with light pollution, which disrupts their nocturnal mating flights.
• The genus name Actias is from the Greek for 'shore' or 'beach', and luna is Latin for 'moon' — a reference to the pale, lunar-green wings and crescent eyespots.