Ottoe skippers are large butterflies, with thick bodies and a wingspan ranging from 29 to 43 mm. The front wings are thin, while the back wings are short and round. Females are usually larger than males. Females and males also have different coloring on their wings. In males, the outer wing surface is usually bright orange with a dark brown border and a black stripe on each front wing. Females have brownish-orange outer wings with dark markings and several white spots near the center. Both males and females have a yellow-orange lower wing surface. This lower wing surface has no markings in males, but females have a light spot on the hindwing. Their antennae are short with knobs on the end, and a sharp tip that points backwards. Since they are strong, fast fliers, they often appear as a blur to the human eye when flying. Hesperia ottoe can be distinguished from other related species of skipper, such as the Dakota skipper (Hesperia dacotae) because the Ottoe skipper is much larger in size. (Cuthrell, 2004; Minnesota Department of Natural Resources, 2014; Selby, 2005)
Hesperia ottoe, a species of butterfly called the Ottoe skipper, can be found from northern Texas through the Great Plains to southwestern Manitoba in Canada. It can also be found east through the prairie region in the United States to northern Indiana and southern Michigan. The Ottoe skipper has been spotted in 14 U.S. states, as well as Manitoba, Canada. (Cuthrell, 2004; Minnesota Department of Natural Resources, 2014)
Ottoe skippers live only in prairie habitats. They can live in many types of prairies, including tall-grass prairies and sand prairies. These prairies must have large amounts of grasses for Ottoe skippers to survive. However, about 99% of prairie habitats in the United States have been destroyed. As a result, Ottoe skippers mainly live in nature preserves that are protected from destruction. (Minnesota Department of Natural Resources, 2014; Shepherd, 2005; Swengel and Swengel, 2013)
Hesperia ottoe undergoes complete metamorphosis. Its life stages are egg, larvae (also known as caterpillars), pupae, and adults. Adults emerge from pupation in late June or July. Shortly after emerging, females search for mates, and mating takes place on plants. Females lay their eggs on plants such as grasses. The eggs hatch after 12 to 13 days. This stage, the larvae, is also commonly called caterpillars. There are 7 larval stages called instars. First, second, and third instar larvae live above the ground in shelters they make from grass blades tied together with silk. They leave these shelters only for short periods of time to gather pieces of grass to eat inside the shelter. Fourth instar larvae move into underground shelters along the bases of grass plants. They then enter the fifth instar and go into hibernation for the winter in their underground shelters. They stay here throughout winter until mid-April to early May, when they leave their underground shelter. They become 6th and 7th stage instars, and build a shelter on the soil surface. In this last shelter, the caterpillar enters, undergoes pupation, and emerges as a butterfly 12 to 19 days later. After this, Ottoe skipper adults live for a few days to a week. (Cuthrell, 2004; Minnesota Department of Natural Resources, 2014; Selby, 2005; Shepherd, 2005)
When ready to mate, female Ottoe skippers search for males. To make themselves visible to females, males usually sit on grasses out in the open so that females can see them. This is called "perching". Sometimes, males will go looking for females themselves, by flying from plant to plant without landing. When a female does find a male, mating occurs also immediately after the pair lands on a plant. Females usually do not mate more than once in their lives, while males will mate as many times as possible. (Minnesota Department of Natural Resources, 2014; Selby, 2005)
The female Ottoe skipper will lay between 180 to 250 eggs in late June or July, one at a time on grasses, which the larvae will eat after hatching. The larvae hatch after 12 to 13 days. Each female will only lay this one batch of eggs during their lifetime. (Selby, 2005)
Females provide nutrients in their eggs for their offspring to grow and develop. Females also lay the eggs on grasses and plants that the caterpillars will eat when they hatch. Adult Ottoe skippers do not provide any more parental care, since they do not return to the eggs after laying them, and most will die before the eggs hatch. (Minnesota Department of Natural Resources, 2014; Selby, 2005)
Adult Ottoe skippers live for a few days to a week. Their entire life cycle, from egg to death, lasts about one year. (Minnesota Department of Natural Resources, 2014)
Since adult Ottoe skippers only live for a few days, their behavior is focused on finding a mate and reproducing. Males spend their time either sitting on plants, waiting for mates, or flying from plant to plant looking for females. When not searching for males, Ottoe skippers spend their time looking for food. They are active during the day. (Selby, 2005)
Ottoe skippers will live and reproduce in the same area that they hatched it, and do not usually move far from this area. (Minnesota Department of Natural Resources, 2014)
There is little known about what senses Ottoe skippers use to gain information about their environment. Sight, smell, and touch are all likely used. To attract mates, Ottoe skippers probably produce chemicals that the skippers can detect and use to find their mates. Males also may gather in groups when sitting on grasses waiting for females. Females may be able to see this and can then find mates that way. (Minnesota Department of Natural Resources, 2014)
Caterpillars feed on small grasses, which they also use to build shelters. Adult Ottoe skippers feed on nectar from flowers. To survive, their habitat needs to have many flowers. (Minnesota Department of Natural Resources, 2014; Selby, 2005; Shepherd, 2005)
Wasps, ants, and other insects will prey on Ottoe skipper eggs and larvae. Crab spiders, ambush bugs, robber flies, and birds prey on adult Ottoe skippers. (Selby, 2005)
Ottoe skippers pollinate the flowers from which they get nectar. They are also preyed upon by many insect predators, as well as birds. (Selby, 2005)
Ottoe skippers do not have any negative effects on humans.
Ottoe skippers pollinate flowers, some of which may be used by humans or important to the habitat. (Selby, 2005)
Ottoe skippers are a threatened species in Minnesota, Michigan, and Illinois, and are also a "species of concern" in Iowa and Montana. This means that in these areas, there are less and less Ottoe skippers. In these areas, Ottoe skippers are having a hard time surviving because of issues in their habitat, as well as the loss of their prairie habitat. One issue is that if there are livestock such as cows in the area, the cows and other animals eat the grass that Ottoe skippers need to lay their eggs on and that the caterpillars need to eat. People also use chemicals, such as herbicides to get rid of weeds, which kill the flowers that the Ottoe skipper needs for nectar. Farmers and other people also use insecticides, which are chemicals to kill unwanted insects, which can also accidentally kill many Ottoe skippers. Both larval and adult Ottoe skippers can also easily be killed by prairie fires. To protect this species from going extinct, it is important to protect their prairie habitat. (Minnesota Department of Natural Resources, 2014; Selby, 2005)
Courtney Hayes (author), Minnesota State University Mankato, Robert Sorensen (editor), Minnesota State University, Mankato, Angela Miner (editor), Animal Diversity Web Staff.
Cuthrell, D. 2004. "Special animal abstract for Hesperia ottoe (ottoe skipper)" (On-line). Michigan Natural Features Inventory. Accessed March 26, 2014 at http://mnfi.anr.msu.edu/abstracts/zoology/Hesperia_ottoe.pdf.
Minnesota Department of Natural Resources, 2014. "Hesperia ottoe" (On-line). Accessed March 15, 2014 at http://www.dnr.state.mn.us/rsg/profile.html?action=elementDetail&selectedElement=IILEP65050.
Selby, G. 2005. Ottoe Skipper: a technical conservation assesment. Society for Conservation Biology: 1-36. Accessed March 25, 2014 at http://www.fs.fed.us/r2/projects/scp/assessments/ottoeskipper.pdf.
Shepherd, M. 2005. "The Xerxes Society for Invertebrate Conservation" (On-line). Species Profile: Hesperia ottoe. Accessed March 26, 2014 at http://www.xerces.org/ottoe-skipper/.
Swengel, A., S. Swengel. 2013. Decline of Hesperia ottoe in Northern Tallgrass Prairie Reserves. Insects, 4: 663-682.