This skipper has a variety of hosts, and appears to be very flexible. Iin Illinois their known hosts include: woolgrass (Scirpus cyperinus), hairy sedge (Carex lacustris), and yellow nut-sedge (Cyperus esculentus).
Nectar Plants
This butterfly is a nectar generalist, often feeding on sneezeweed (Helenium autumnale), buttonbush (Cephalanthus occidentalis), and pickerelweed (Pontederia cordata).
Other host species
The hosts used by populations outside of Illinois include shoreline sedge (Carex hyalinolepis), which may be used in the southern and coastal portions of the range.
photo of hairy sedge while in flower
Habitat
The butterfly is associated with wetlands of many kinds including open marshes, bogs, and swamps. In Illinois the host plants tolerate temporal wetlands and wet prairies.
"Scirpus cyperinus" by dogtooth77 is licensed under CC BY-NC-SA 2.0
Dion skipper and habitat
Population Dynamics
The species is fairly widespread, but exists in mostly low density.
There is likely a network of metapopulations in a region with the highly mobile butterfly moving between patches.
Male territoriality likely affects the population structure and movement, leading to more dispersed adults, and presence outside of natal patches.
Studies on dispersal, population sizes, and population structure are needed.
Life Cycle
01 / 06
Life Cycle
Dion skipper's life cycle varies with latitude. The southern populations have two broods each year (bivoltine) and the northern populations, in Illinois, have only one (univoltine).
Adults
Adults fly from July-August in Illinois. Males are territorial, finding perches to await females to mate.
Eggs
The butterflies place their eggs singly on host plant leaves.
Caterpillars
Caterpillars overwinter as third instars (about half sized), consuming hostplant in the summer but finishing development in the spring.
Chrysalis
Like most skippers they form their chrysalis in a nest of folded leaves and silk.
Voltinism Changes
Under climate change, Dion skippers may begin to have partial generations, or developmental traps.
Conservation
Listing Status
Dion skippers are listed as vulnerable in Illinois. They are most at risk in Delaware and North Dakota, and they are not ranked as secure for any state. This is possibly due to a lack of data and ranking for certain states.
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 the Dion skipper. Conservation efforts for Dion skipper habitat also benefit others living in the region, such as Baltimore checkerspot and black dash. Actions include 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 black dash 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
At four sites we so no association of changes in phenology with varying trends in phenology and abundance, which includes data after 2015 for three of the sites.
Activity trends through time each year for two Dion skipper sites.
Activity trends through time each year for two Dion skipper sites.
