Distribution of Carrion Beetles (Coleoptera: Silphidae) in Different Geographic Regions of Virginia Shana Margaret Beirne Thesis submitted to the faculty of the Virginia Polytechnic Institute and State University in partial fulfillment of the requirements for the degree of Master of Science in Life Sciences in Entomology Richard D. Fell Douglas G. Pfeiffer Donald E. Mullins 7 December 2012 Blacksburg, VA Keywords: Silphidae, Nicrophorus, silphids, baited pitfall traps © 2012, Shana Margaret Beirne Distribution of Carrion Beetles (Coleoptera: Silphidae) in Different Geographic Regions of Virginia Shana Margaret Beirne ABSTRACT The distribution of beetles in the Family Silphidae has not been well studied in Virginia. The primary purpose of this study was to survey silphid beetles in a more systematic manner across different geographic regions of the state, with a special consideration for Nicrophorus species. The seasonal abundance and diversity of silphid beetles in Montgomery County, Virginia, was also examined. Baited pitfall traps were used to sample beetle distribution and abundance, and were placed in each of the five geographical regions of Virginia in the summers of 2007 and 2008. Traps were placed approximately one kilometer apart and were checked daily over a five day period for each of three sampling periods. A total of 4375 silphid beetles, consisting of 11 species in four genera, were collected in ten counties with beetles in the subfamily Silphinae being predominant. Within the Nicrophorinae, Nicrophorus tomentosus and N. orbicollis were dominant in 2007; whereas in the summer of 2008, N. tomentosus and N. pustulatus were the most commonly collected. Contingency analyses indicated that species abundance was associated with sampling period and geographic region. Nicrophorus americanus was not collected during either summer of surveying and only three N. carolinus were trapped in Suffolk County in the summer of 2008. For the Montgomery County survey, a total of 3276 beetles were found between the middle of April and the middle of October. The prevalent species within Nicrophorinae was Nicrophorus tomentosus and within the Silphinae it was Necrophila americana. Species abundance was associated with sampling period. DEDICATION I would like to dedicate this thesis to my parents, Mimi and Ob, and Dad; my fiancé, Eric; Eric’s mom, Gloria; and the Entomology Department. If it were not for my parents, I never would have had the drive to finish what I had started in life. They always stood behind me, rooting me on, pushing me when I was slacking off, and helping me (emotionally and financially) whenever I needed it most. Without their support, I would not be where I am today. I would not even be in grad school if it were not for my fiancé, Eric. He helped me realize that no matter what, I needed to follow my dreams and that I should pursue my passion for insects. Eric has been my rock to lean on when I stopped believing in myself, and helped financially whenever possible. Gloria, who has a heart of gold, graciously accepted me into her family and always understood when I was too busy to come see her. If it were not for the extra push and the kick in the pants from the Entomology Department when I needed it the most, this never would have been completed. iii ACKNOWLEDGMENTS I would like to acknowledge funding support from the Virginia Department of Agriculture and Consumer Services. I would especially like to thank the students and staff in the Entomology Department, they have been extremely supportive and patient with me. Dr. Kok, who has always been interested in students’ projects, would listen every time I needed an ear to chew on or someone to bounce ideas off of. My major advisor and my mentor, Dr. Fell, helped me tremendously with every aspect of my research, giving me brilliant ideas when I was stuck, and pulling me out of a rut every once in a while. My co-advisor, Dr. Pfeiffer, was there for me, to listen to, to bounce ideas off of, and gave me plenty of feedback on my project. Dr. Mullins, a member of my committee, has helped me more than he knows. He was there for me two years before I started grad school, guiding me in the classes I needed before I could get accepted, and I kept him up to date with my progress. He went above and beyond his job as a graduate coordinator. Even now, he has helped me with certain aspects of my research. My GPS data would have been non-existent without Andy Roberts, so I would like to thank him greatly for all the hard work he put in (especially when he had to redo everything due to my inexperience in surveys). The grad students in the Entomology Department have been extremely helpful as well. They were always available to talk about research issues and lend fresh ideas when I have been stuck and no one else was available. Last, but certainly not least, I would have no data analyses without Dr. Brewster. He pulled me out of the fire and my thesis could not have been finished without him. iv For the summer of 2007: I would like to thank University of Virginia-Wise for a place to stay while surveying in Wise County. I would like to thank the following individuals: Len DiIola at the Radford Arsenal for being so helpful. Colonel Ronald Fizer for allowing me to survey on government property in Pulaski County. Harvey Thompson at Grayson Highlands State Park. Dr. Paul J. Semtner for allowing me to survey at Southern Piedmont Agricultural Research and Extension Center in Nottoway County. Lakshmipathi Srigiriraju, and everyone else at Blackstone who helped me put my traps in, and Fort Pickett for allowing me to stay on the military base. Dr. Thomas P. Kuhar for allowing me to survey at the Eastern Shore Agricultural Research and Extension Center. Meredith Cassell and others for putting in my traps and checking them throughout the summer in Accomack County. For the summer of 2008: I would also like to thank the following individuals: Derek Monthei for checking my Montgomery County traps while I was checking my traps throughout Virginia, and Aaron Mullins for checking my food preference traps at Moore Farm in Montgomery County. The Clinch Ranger District for allowing me to survey in the Jefferson National Forest in Dickenson County. Mr. Mullins for allowing me to survey and stay at Breaks Interstate Park. Douthat State Park for allowing me to survey in their park in Bath County. v The Ranger Station at Natural Bridge for allowing me to survey in the Cave Mountain Lake Recreation Area in Rockbridge County. Appomattox-Buckingham State Forest in Appomattox County for allowing me to survey there; and Mr. and Mrs. W.K. Fell for letting me stay in their guesthouse. They were the most wonderful people to help me out. Don Schwab and the staff at the Great Dismal Swamp National Wildlife Refuge office for allowing me to survey in the Great Dismal Swamp in Suffolk County, and for helping to check my traps when I was not there. vi TABLE OF CONTENTS DEDICATION . iii ACKNOWLEDGEMENTS . iv LIST OF FIGURES . ix LIST OF TABLES . xii 1. INTRODUCTION . 1 2. COLEOPTERA: SILPHIDAE . 3 2.1 BACKGROUND . 3 2.2 EVOLUTION, PHYLOGENY AND CURRENT CLASSIFICATION . 6 2.3 LIFE HISTORY . 11 2.3.1 Behavior and Feeding . 11 2.3.2 Development . 12 2.3.3 Feeding Preferences . 13 2.4 AMERICAN BURYING BEETLE . 13 2.4.1 Historical and Current Range of Nicrophorus americanus Olivier . 13 2.4.2 American Burying Beetle Surveys . 16 3. SURVEY OF SILPHID BEETLES IN VIRGINIA, WITH SPECIAL CONSIDERATION FOR NICROPHORUS SPECIES . 17 3.1 INTRODUCTION . 17 3.2 METHODS AND MATERIALS . 20 3.2.1 Trap Placement and Data Collection . 20 3.2.2 Statistical Analysis of the Data . 30 3.3 RESULTS . 31 3.3.1 Contingency Analysis of Species by Sampling Period (with Region as a Blocking Factor) for Commonwealth Surveys . 32 3.3.2 Contingency Analysis of Species by Geographic Region (with Year as a Blocking Factor) for Commonwealth Surveys . 40 3.3.3 Contingency Analysis of Species by Site . 42 3.3.4 Contingency Analysis of Species by Period (with Site as a Blocking Factor) for Montgomery County Survey . 44 3.3.5 Contingency Analysis of Species by Month (with Site as a Blocking Factor) for Montgomery County Survey . 46 3.4 DISCUSSION . 48 4. SUMMARY . 53 REFERENCES . 55 vii APPENDIX A. CONTINGENCY TABLE OF SPECIES BY PERIOD FOR THE COMMONWEALTH OF VIRGINIA . 59 APPENDIX B. CONTINGENCY TABLE OF SPECIES BY REGION FOR THE COMMONWEALTH OF VIRGINIA . 60 APPENDIX C. CONTINGENCY TABLE OF SPECIES BY PERIOD FOR MONTGOMERY COUNTY, VA . 61 APPENDIX D. CONTINGENCY TABLE OF SPECIES BY MONTH FOR MONTGOMERY COUNTY, VA . 62 APPENDIX E. CONTINGENCY TABLE OF SPECIES BY SITE FOR MONTGOMERY COUNTY, VA . 63 viii List of Figures: Figure 1. Current and reported historical range of the American burying beetle. (Map - US Fish and Wildlife Service, Oklahoma Ecological Services Field Office, August 8, 2004) (http://eol.org/pages/1044544/details) . 15 Figure 2. Locations in Virginia where silphid traps were set up in summers 2007 and 2008. Summer 2007, Traps 1 – 5, sites are labeled in Red Circles. Summer 2008, Traps 6 – 10, sites are labeled in Blue Triangles. Trap locations were: Trap 1 – Wise County; Trap 2 – Pulaski County; Trap 3 – Grayson County; Trap 4 – Nottoway County; Trap 5 – Accomack County; Trap 6 – Dickenson County; Trap 7 – Bath County; Trap 8 – Rockbridge County; Trap 9 – Appomattox County; Trap 10 – Suffolk County. (Virginia Department of Education - http://www.doe.virginia.gov/testing/sol/standards_docs/history_socialscience/index.shtml) .