South Dakota State University Open PRAIRIE: Open Public Research Access Institutional Repository and Information Exchange Electronic Theses and Dissertations 2020 The Status of Dakota Skipper (Hesperia dacotae Skinner) in Eastern South Dakota and the Effects of Land Management Kendal Annette Davis South Dakota State University Follow this and additional works at: https://openprairie.sdstate.edu/etd Part of the Entomology Commons Recommended Citation Davis, Kendal Annette, "The Status of Dakota Skipper (Hesperia dacotae Skinner) in Eastern South Dakota and the Effects of Land Management" (2020). Electronic Theses and Dissertations. 3914. https://openprairie.sdstate.edu/etd/3914 This Thesis - Open Access is brought to you for free and open access by Open PRAIRIE: Open Public Research Access Institutional Repository and Information Exchange. It has been accepted for inclusion in Electronic Theses and Dissertations by an authorized administrator of Open PRAIRIE: Open Public Research Access Institutional Repository and Information Exchange. For more information, please contact [email protected]. THE STATUS OF DAKOTA SKIPPER (HESPERIA DACOTAE SKINNER) IN EASTERN SOUTH DAKOTA AND THE EFFECTS OF LAND MANAGEMENT BY KENDAL ANNETTE DAVIS A thesis submitted in partial fulfillment of the requirements for the Master of Science Major in Plant Sciences South Dakota State University 2020 ii THESIS ACCEPTANCE PAGE KENDAL ANNETTE DAVIS This thesis is approved as a creditable and independent investigation by a candidate for the master’s degree and is acceptable for meeting the thesis requirements for this degree. Acceptance of this does not imply that the conclusions reached by the candidate are necessarily the conclusions of the major department. Paul Johnson Advisor Date David Wright Department Head Date Dean, Graduate School Date iii AKNOWLEDGEMENTS First and foremost, I want to thank my advisor, Dr. Paul J. Johnson, for the opportunity to do this fantastic project. I appreciate all of his patience and mentoring. I would like to thank my committee members, Dr. Arvid Boe and Dr. Nicholas Butzin, for taking the time to participate in my defense. A huge thank you to the Sisseton Wahpeton Oyate for letting me survey for Dakota skipper on their land. A big thank you to Dennis Skadsen, who has been nothing but a wealth of knowledge on Dakota skipper and the Prairie Coteau. Thank you to Jacob Dyer for being my South Dakota Game, Fish and Parks contact and helping me get data. Many thanks to the numerous others who helped with gather data and site history for this project. I am extremely thankful for Anna Kate Lacy and Benjamin Scrivener who have listened to me talk about this project and kept me awake on the drives back to Brookings, SD, after long days in the field. Your encouragement has meant the world to me. Thank you both for understanding and putting up with me. A big thank you to Dr. Katherine Parys for sending me the email about this project. I honestly don’t think I would have gotten this far without your pushing and encouragement. I am also grateful to Caleb Kellough (G.Deetz) and the G.Deetz community for being such an amazing and encouraging group of people. You helped me get through so many stressful days with your crazy antics and being an awesome group of people. Finally, I’d like to give a big thank you to my family. They have been my cheerleaders through all of this. I’m so thankful that they have supported me, even though iv they don’t really understand what I do. Honestly, none of this would have been possible without their support. v TABLE OF CONTENTS Page LIST OF FIGURES . vii LIST OF TABLES . viii ABSTRACT . ix INTRODUCTION . 1 Habitat . 4 Distribution and Range . 7 Threats . 12 Objectives . 14 METHODS AND MATERIALS . 15 Site Selection . 15 Study Sites . 16 Data Collection . 18 RESULTS . 19 Hesperia dacotae Observations . 21 General Butterfly Surveys . 26 DISCUSSION . 26 Identification Difficulties . 26 Weather . 29 Privately-owned Land . 36 Site History . 37 Habitat Degradation . 38 Grazing . 39 Fire . 44 Haying . 49 CONCLUSION . 50 vi Future Research Directions . 51 TABLES . 53 REFERENCES . 63 APPENDICES . 69 vii LIST OF FIGURES Page Male and female Hesperia dacotae . 1 The stigma on male Hesperia dacotae. 2 Female Hesperia dacotae on Echinacea angustifolia . 7 Historical range of Hesperia dacotae . 8 Current range of Hesperia dacotae . 9 2019 sites with Hesperia dacotae observations . 12 East Blue Dog, Day County . 20 Scarlet Fawn Prairie, Day County in July . 21 Location of the female H. dacotae found at Goodboy Prairie in 2018 . 22 Path (white curved line) following the ridgeline at Goodboy Prairie . 23 Locations of Hesperia dacotae adults caught at Owl Lake Prairie in 2018 . 24 Inhabited sites in eastern South Dakota in 2019 . 25 Males and females of similar skippers in the study area . 29 Hayes Prairie surrounded by agricultural land . 44 Distance between Scarlet Fawn Prairie and Hayes Prairie . 48 viii LIST OF TABLES Page List of Hesperia dacotae sites by ownership . 17 Hay dates of tribe owned sites . 53 Historical Hesperia dacotae observations for survey site . 54 2018 list of non-target species . 55 2019 list of non-target species . 59 ix ABSTRACT THE STATUS OF DAKOTA SKIPPER (HESPERIA DACOTAE SKINNER) IN EASTERN SOUTH DAKOTA AND THE EFFECTS OF LAND MANAGEMENT KENDAL ANNETTE DAVIS 2020 Hesperia dacotae (Skinner, 1911) (Insecta: Lepidoptera), also known as Dakota skipper, is a northern Great Plains species of butterfly associated with tall or mixed grass prairies. Its range once extended from southern Manitoba, southeastern Saskatchewan, North Dakota, South Dakota, Minnesota, to Iowa and Illinois. Now H. dacotae is only found in small isolated pockets in southern Manitoba, southeastern Saskatchewan, North Dakota, South Dakota, and Minnesota. The species is often observed on alkaline prairies with poor soil not desirable for cultivation. Thus, many of the historical H. dacotae are used for pasturing cattle or as hay prairie. The loss of habitat has been one of the greatest factors to H. dacotae decline. In 2014, H. dacotae was listed as “Threatened” under the Endangered Species Act. H. dacotae as endangered since March 2018. This study surveyed H. dacotae in eastern South Dakota, looking at inhabited sites, historical sites and non-historical sites. There were 10 state owned sites, 9 tribal owned sites and 1 privately owned site. Management of prairie remnants has played an important role in whether a population of H. dacotae has persisted on the site. Many of the inhabited sites were used as fall hay prairies. One site was hayed earlier than August in 2014 and several years after and H. dacotae has not seen on the site since. Sites that once had H. dacotae that were grazed did not have any observations of H. dacotae in the two years of this study. To protect the remaining populations of H. dacotae, land management practices need to be at the forefront. 1 INTRODUCTION Hesperia dacotae (Skinner, 1911) (Insecta: Lepidoptera), also known as Dakota skipper, is a northern Great Plains species of butterfly associated with alkaline prairies. This species was described from adults collected at Volga, South Dakota, and Grinnell, Iowa (Skinner 1911, McCabe 1981) (Figure 1). Its range once extended from southern Manitoba, southeastern Saskatchewan, North Dakota, South Dakota, and Minnesota to Iowa and Illinois. Now H. dacotae is found in only isolated pockets in southern Manitoba, southeastern Saskatchewan, North Dakota, South Dakota, and Minnesota. Figure 1. Male and female Hesperia dacotae. ©Tim Poole/www.discoverlife.org. As a member of the family Hesperiidae, H. dacotae is distinguished from other butterflies by a thick, strong thorax and comparatively short wings that enable them to fly in powerful bursts or “skips” (Layberry et al. 1998). The species is a small to medium- sized skipper that has an adult wingspan ranging from 2.4 cm (<1 inch) to 3.2 cm (1.26 inches) and a maximum larval size that ranges from 19 mm (0.74 inches) to 22 mm (0.87 inches) long (Narem 2015). The dorsal surface of the adult male wings is a tawny-orange color with a prominent dark stigma on the forewing, while the ventral side of the wings is a dusty yellow-orange with some lighter mottling (Figure 2). The dorsal surface of the adult female wings is a darker brown with cream-colored spots on the forewing. On the 2 ventral surface of the wings is a dusty grayish brown with a faint white mottling across the middle of the wing. This coloration is similar to several other grass skippers, which could confuse the untrained eye. Figure 2. The stigma on male Hesperia dacotae. ©Tim Poole/www.discoverlife.org. Hesperia dacotae is a univoltine species of Hesperia, completing one generation per year (Narem 2015). The females lay their eggs close to the ground on any broad surface, with some preference given to broad-leaved plants (McCabe 1981). The female will continue to lay eggs throughout.