ODNR Division of Wildlife - A to Z Species Guide - Butterflies and Skippers - Edward's Hairstreak

 Edward's Hairstreak


Photo by Jim McCormac		 Edward's hairstreaks were once thought to be a threatened species, but it is now known from Jackson, Scioto, Adams, Highland, Brown, Pike, Lucas, Fulton, and Holmes counties. New colonies of this butterfly should be reported to the Division of Wildlife.

Edward's Hairstreak
Satyrium edwardsii

At-a-Glance

• Flight Period: June and July

• Wings: 1.18 - 1.46 inches
Description
Hairstreaks get their name from "hair-like" tails that extend from their hindwings. An "eye spot" of red or blue usually accompanies the tails. This tail is thought to function as a protective device that fools predators into thinking it is the antennae or head of the butterfly.

Habitat and Habits
Edward's hairstreak inhabits cedar glades and savannas (it is always in association with the red Appalachain ant, Formica exsectoides).

Reproduction and Care of the Young
Edward's hairstreak is interesting because ants tend to the larvae of this species. The ants receive sweet nectar from the larvae and in turn provide protection for the larvae and adult butterflies. The easiest way to find a colony of Edward's hairstreak is to look for large ant mounds in association with small oak trees. Colonies have hundreds of adults during their flight season, but are intensely local and easily overlooked. The larvae feed on black oak in Ohio, and other oaks are suspected as well.