Hesperia ottoe

Geographic Range

Historically, the Ottoe skipper occupies a range from northern Texas through the Great Plains to southwestern Manitoba, and east through the tallgrass prairie region to northern Indiana and southern Michigan. This skipper has been reported in 14 U.S. states as well as Manitoba, Canada.

• Biogeographic Regions
• nearctic nearctic
  • native native

Habitat

Hesperia ottoe is a prairie-dependent species and is found in a wide range of prairie types, from undisturbed tall-grass and mixed-grass prairies on the Great Plains to dry or sand prairies near the Great Lakes. It is typically found in areas where mid-height grasses such as little bluestem, prairie dropseed and side-oats grama are a major component of the vegetation. However, around 99% of tall-grass prairie has been destroyed, restricting the Ottoe skipper's habitat mainly to nature preserves.

• Habitat Regions
• temperate temperate
• terrestrial terrestrial

• Terrestrial Biomes
• savanna or grassland savanna or grassland

Physical Description

Hesperia ottoe is a large, stout species of butterfly called skippers, with a wingspan ranging from 29 to 43 mm. This skipper has a thick body, with thin, angular forewings, and shorter, more rounded hind wings. Females have a tendency to be larger than males. For males, the outer wing surface is typically bright orange with a dark brown border and a distinct black stigma (specialized scent scales) on the forewing. Females have brownish-orange outer wings with dark markings and several off-white translucent spots near the center of the forewing. Both sexes have a yellow-orange lower wing surfaces. This lower wing surface is unmarked in males, but females have a faint post-median spot on the hindwing. Their antennae are short with clubbed ends and a sharp tip that points backwards. Since they are strong, fast fliers, they often appear as a blur to the human eye when in flight. Hesperia ottoe is distinguishable from the closely related Dakota skipper ( Hesperia dacotae ) by its significantly larger size.

• Other Physical Features
• ectothermic ectothermic
• heterothermic heterothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• female larger
• sexes colored or patterned differently
• male more colorful

Development

Hesperia ottoe is univoltine and has a single annual generation. The entire life cycle must be successfully completed each year for the population to persist in that region. Adults emerge from pupae in mid to late June or July, with males emerging a few days before females. Shortly after emerging, females will search for a mate, and mating then takes place on host plants. The female will deposit the eggs on host grasses or forbs. The eggs will hatch in approximately 12 to 13 days. There are 7 larval instars (stages) for this species. First through third instar larvae live above ground in shelters they construct from grass blades tied with silk one to two inches above the soil, emerging for only brief periods to gather pieces of grass to consume within their shelter. They will construct 2 to 3 of these shelters in the first three instars. Fourth instar larvae shift to subterranean shelters formed among the bases of grass culms. They then enter the fifth larval instar, during which they enter winter diapause within their buried shelter. They will remain at this fifth larval instar until mid-April to early May, when they emerge from their underground shelter and enter the 6th and 7th larval instars, during which they construct a horizontal shelter along the soil surface. Within this final shelter pupation occurs. The adults will finally emerge 12 to 19 days after pupation. The life expectancy for adults of this species is a few days to a week.

• Development - Life Cycle
• metamorphosis metamorphosis
• diapause diapause

Reproduction

For male Ottoe skippers , "perching" is the primary mate-seeking behavior, during which they station themselves near host plants awaiting the arrival of a female. Males sometimes also exhibit "searching" behavior, during which they search for females by flying rapidly from host plant to host plant without landing. Receptive females will descend upon host vegetation to meet the male. Mating occurs immediately after the pair lands on the host vegetation. Females rarely mate more than once, while males mate as much as possible .

• Mating System
• polygynous polygynous

The female Ottoe skipper will lay between 180 to 250 eggs in late June or July, singly on host grasses or forbs, which are suitable for the larvae to eat. The first larval stage will hatch after 12 to 13 days. Each female produces a single brood in their lifetime.

• Key Reproductive Features
• semelparous semelparous
• seasonal breeding seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• fertilization fertilization
  • internal internal
• oviparous oviparous

Females provide provisioning in their eggs, as well as lay the eggs on a suitable host plant that the larvae can feed on after hatching. Adults provide no more parental care, most likely dying before their offspring hatch.

• Parental Investment
• pre-hatching/birth
  • provisioning
    • female

Lifespan/Longevity

Adult life expectancy of H. ottoe is a few days to a week in the wild. The complete life cycle for an Ottoe skipper lasts approximately one year, including winter diapause.

Behavior

Since adults of this species only live for a few days, their behavior is focused on finding a mate, reproducing, and ovipositing. Males will either "perch or search", meaning that they will either wait near host plants for receptive females or actively fly from host plant to host plant searching for them. When not searching for mates, they are foraging for food. They are active during the day.

• Key Behaviors
• flies
• diurnal diurnal
• motile motile
• sedentary sedentary
• hibernation hibernation

Home Range

Ottoe skippers will live and breed in the same region they hatch in, and do not typically disperse.

Communication and Perception

There is little information available about how Hesperia ottoe communicates with others and perceives the environment. It is also unclear how mates attract one another; it is likely pheromones and other chemicals are secreted. Males also loosely aggregate when searching for mates, which may be a visual clue for females.

• Communication Channels
• visual visual
• chemical chemical

• Other Communication Modes
• pheromones pheromones

• Perception Channels
• visual visual
• acoustic acoustic
• chemical chemical

Food Habits

Larvae feed primarily on small bunch grasses such as little bluestem , which are the most suitable for consumption and shelter building. Adult Hesperia ottoe are nectar feeders and require an abundance of flowers to maintain a stable population. Nectar sources include milkweed, purple coneflowers, vetch, alfalfa, leadplant, compassplant, sunflower, and blazing star. When not in search of a mate, adults spend their time foraging.

• Primary Diet
• herbivore herbivore
  • nectarivore nectarivore

• Plant Foods
• leaves
• nectar

Predation

Some predation of Ottoe skipper eggs and larval stages by various groups of wasps, ants, and other insects has been observed. Some potential predators of adult Ottoe skippers include crab spiders , ambush bugs , robber flies , and birds.

Ecosystem Roles

Ottoe skippers act as pollinators for the flowers which provide them with nectar. They also serve as prey to a variety of invertebrate predators, as well as birds.

• Ecosystem Impact
• pollinates

Economic Importance for Humans: Positive

Hesperia ottoe pollinates flowers, some of which may be of economic importance to humans and ecosystems.

Economic Importance for Humans: Negative

There are no known adverse effects of Hesperia ottoe on humans.

Conservation Status

Hesperia ottoe is listed as "threatened" in the states of Minnesota, Michigan, and Illinois, and as a "species of concern" in Iowa and Montana. Habitat destruction is the primary threat to this species. The Ottoe skipper is sensitive to grazing, and heavy periods of grazing can eliminate it from the area even if the prairie is not degraded. Use of herbicides can eliminate the flowers and nectar that the Ottoe skipper depends upon for nourishment, and insecticides from nearby areas of agriculture can eliminate populations of skippers. Small, isolated colonies of Ottoe skippers are at high risk for extirpation resulting from both natural events (such as strong storms or drought) and human caused events. Prairie fires can kill both larval and adult stages of H. ottoe . The protection of this species mainly involves the protection of prairie habitat. Much of the prairie habitat supporting the two largest known Ottoe skipper populations in Minnesota is protected through ownership and management by public or private conservation agencies and organizations. Hesperia ottoe does not have any legal protection at the national level in the United States.

Additional Links

Encyclopedia of Life

BioKIDS Critter Catalog

Contributors

Courtney Hayes (author), Minnesota State University Mankato, Robert Sorensen (editor), Minnesota State University, Mankato, Angela Miner (editor), Animal Diversity Web Staff.

References

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.