Host plants include various sedges, such as tussock sedge (Carex stricta), pictured here.
Closeup of the flowering heads of tussock sedge.
Nectar Plants
Adult eyed browns feed on sap, rotting fruit, and bird droppings. They only occasionally feed on flower nectar, such as swamp milkweed (Asclepias incarnata).
An eyed brown butterfly sits on a brown branch.
Habitat
Eyed browns live in sedge meadows, alongside slow-moving streams, freshwater marshes, and swales in tallgrass prairies.
An eyed brown butterfly perches on a green leaf nestled in grasses and branches.
Tussock sedge grove against a grove of trees by a small creek.
An eyed brown butterfly feeds on a milkweed flower while hanging upside down.
Tussock sedge plants next to a stream.
An eyed brown butterfly perches on a green leaf in the bright sunlight.
Tussock sedge grasses in a marshy area with trees and lilypads.
Eyed brown and habitat
Population Dynamics
Current populations of eyed brown are isolated from one another. Many areas that had once been occupied are now unoccupied.
Adults are sedentary, perch frequently, and fly weakly throughout vegetation. They do not tend to disperse in large numbers. Males patrol through vegetation and sometimes perch to court females.
Life Cycle
Adult
These butterflies are univoltine, producing a single brood each year. Adults fly from mid-June to mid-September.
An eyed brown butterfly perches on a leaf with its wings closed.
Eggs
Females lay eggs singly and scattered near a host plant. Eggs look similar to this Appalachian brown egg.
Caterpillars
Caterpillars, that look similar to this Appalachian brown, feed on sedge grasses, and when they're in the third or fourth instar, they overwinter.
Voltinism
Other members of the genus Lethe have flexible voltinism. If climate change continues, this species may have propensity to do so.
Conservation
Listing Status
The eyed brown is globally listed as secure. It is vulnerable in Illinois and Indiana. The species may have experienced range contraction on the edges of the range. The butterfly is most secure in New Hampshire and most provinces in Canada including: Ontario, New Brunswick, Nova Scotia, and Prince Edward Island.
Recovery Efforts
Abundance Surveys and Habitat Maintenance
The Forest Preserve District of DuPage County in Illinois (FPDDC) conducts regular Pollard-walk relative abundance surveys for eyed brown. Conservation efforts are applied to benefit a larger community of butterflies, which include Baltimore checkerspot and broad-winged skipper. Actions involve prescribed fire, removing and burning brush, and manual removal of invasive species.
Illinois Wildlife Action Plan
Illinois Wildlife Action Plan has two campaigns to preserve and improve wildlife habitats that include Eyed brown habitat: Wetland Campaign , and Farmland and Prairie Campaign . However, these programs currently only target vertebrate species for conservation, like this blue-spotted salamander from Cook County, IL.
Population Trends
Eyed browns had enough data to be analyzed at ~10 sites, spanning from 1987-2019 at some sites. with most sites having data until ~2015. We saw no association of phenology and abundance. At about half of the sites we observed declines, some had no change, and at only two sites was there an increase in the activity index. Some sites had no phenological change, with an equal amount having advances and one was delayed.
Example of activity trends through time each year for an eyed brown site.
Example of activity trends through time each year for an eyed brown site.
