University of Arkansas, Fayetteville ScholarWorks@UARK Theses and Dissertations 12-2014 Population Genetics, Distributions and Phenology of Bombus Latreille, 1802 and Xylocopa Latreille, 1802 (Hymenoptera: Apidae) Amber Dawn Tripodi University of Arkansas, Fayetteville Follow this and additional works at: http://scholarworks.uark.edu/etd Part of the Agriculture Commons, Biology Commons, and the Entomology Commons Recommended Citation Tripodi, Amber Dawn, "Population Genetics, Distributions and Phenology of Bombus Latreille, 1802 and Xylocopa Latreille, 1802 (Hymenoptera: Apidae)" (2014). Theses and Dissertations. 2132. http://scholarworks.uark.edu/etd/2132 This Dissertation is brought to you for free and open access by ScholarWorks@UARK. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of ScholarWorks@UARK. For more information, please contact [email protected], [email protected]. Population Genetics, Distributions and Phenology of Bombus Latreille, 1802 and Xylocopa Latreille, 1802 (Hymenoptera:Apidae) Population Genetics, Distributions and Phenology of Bombus Latreille, 1802 and Xylocopa Latreille, 1802 (Hymenoptera:Apidae) A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Entomology by Amber Dawn Tripodi University of Arkansas Bachelor of Science in Biology, 2005 University of Colorado Master of Science in Environmental Sciences, 2009 December 2014 University of Arkansas This dissertation is approved for recommendation to the Graduate Council. _______________________________ Dr. Allen L. Szalanski Dissertation Director _______________________________ _______________________________ Dr. Jeffery K. Barnes Dr. Donn T. Johnson Committee Member Committee Member _______________________________ _______________________________ Dr. Marlis R. Douglas Dr. Kenneth L. Kvamme Committee Member Committee Member ABSTRACT This work addresses multiple knowledge gaps in bee ecology, population health and phylogeography in order to provide insights into the changing distributions of native bees. A comparison of Arkansas bumble bee records mirrors range-wide surveys, with records of stable species (Bombus bimaculatus Cresson, 1863 and B. impatiens Cresson, 1863) increasing three- fold, and records of the declining B. pensylvanicus (DeGeer, 1773) dropping to 60% of historical levels. However, nationally-recommended conservation-genetics tools did not mirror these results on a regional level. Stable and declining species had equivalent genetic diversity in samples from Arkansas and Tennessee (HS range: 0.46–0.63). Diploid males, which indicate inbreeding, were only detected in the species known to be stable, B. bimaculatus and B. impatiens. This could be an indication of broad similarity of these taxa in the region, or it could indicate that recommended microsatellite-based tools are less likely to detect genetic signatures of declines at a localized level. A three-year survey of floral associations and seasonality in a community of eight bee species across Northwest Arkansas found that local and landscape factors had no effect on the differential abundances of this community, but overall abundance increased with increasing plant richness at each site (F(1,11)=45.62, p<0.001), as did the abundance of each bumble bee species. Bumble bees with long glossae, a group usually thought to be at higher risk of decline, were more specialized in their flower use, and although their food choices overlapped (O12=0.54), they skirted potential competition by maintaining different phenologies. Subspecies status was maintained for Xylocopa virginica texana Cresson, 1872, but not for X. v. krombeini Hurd, 1961. This morphological east-west differentiation is additionally supported by mitochondrial phylogeographic analyses which suggest that X. virginica expanded from multiple glacial refugia. On the other hand, X. micans haplotypes are consistent with a single origin, likely west of the Mississippi River. In spite of its interpopulation homogeneity, X. micans is quite genetically diverse (Hd=0.91±0.03) compared to X. virginica and (Hd=0.78±0.02), consistent with Hewitt’s leading-edge hypothesis for range disparity. Together, these results highlight the importance of an ecological perspective in the quest to understand bee distributions and decline. ACKNOWLEDGEMENTS I would like to thank a number of people that have aided me in my endeavors, although none of them are to blame for the results. Firstly, I wish to thank my advisor, Allen Szalanski for the unwavering support, encouragement, advice and guidance he has provided throughout the years. I would also like to thank my committee members, Marlis Douglas, Jeffery Barnes, Donn Johnson and Kenneth Kvamme for always being willing to help and offer encouragement, whether my crises were scientific or existential. I extend the deepest gratitude to my companions in the department, Susan Osredker, Soo-Hoon (Sam) Kim, Ace Lynn-Miller, Bryan Petty, Mark Janowiecki and Clinton Trammel whose willingness to join me in adventures and conversations kept me both sane and engaged over the years. I also thank my parents, Lloyd Tripodi and Dawn Hall for their overwhelming enthusiasm and encouragement. Finally, none of this would have been possible without the incredible support of my best friend, Josh Gladwin, without whom I would have forgotten to eat and never would have dreamed of pursuing a Ph.D. TABLE OF CONTENTS LIST OF TABLES LIST OF FIGURES LIST OF APPENDICES I. INTRODUCTION ..........................................................................................................................1 A. BEES AND POLLINATION ...............................................................................................1 B. A REVIEW OF THE POTENTIAL CAUSES OF BUMBLE BEE DECLINE ...............................2 C. CONTRASTS OF DIVERSITY AND DISTRIBUTION IN CARPENTER BEES ........................ 23 D. REFERENCES ...............................................................................................................29 II. THE BUMBLE BEES OF ARKANSAS, FIFTY YEARS LATER ........................................................42 A. ABSTRACT ..................................................................................................................42 B. INTRODUCTION .......................................................................................................... 42 C. MATERIALS AND METHODS ........................................................................................44 D. RESULTS .....................................................................................................................46 E. DISCUSSION ............................................................................................................... 47 F. SPECIES ACCOUNTS ....................................................................................................51 G. ACKNOWLEDGMENTS ................................................................................................ 61 H. REFERENCES ...............................................................................................................61 III. A MATTER OF SCALE: USING POPULATION GENETICS TO ASSESS THE CONSERVATION STATUS OF BUMBLE BEE POPULATIONS ............................................................................... 69 A. ABSTRACT ................................................................................................................. 69 B. INTRODUCTION .......................................................................................................... 69 C. MATERIALS AND METHODS ........................................................................................71 D. RESULTS .................................................................................................................... 75 E. DISCUSSION ............................................................................................................... 77 F. ACKNOWLEDGMENTS ................................................................................................. 79 G. REFERENCES .............................................................................................................. 80 H. APPENDICES .............................................................................................................. 87 IV. PRELIMINARY SURVEY FOR DIPLOID MALES IN A FEW POPULATIONS OF BOMBUS LATREILLE, 1802 (HYMENOPTERA: APIDAE) USING MICROSATELLITES .............................. 92 A. ABSTRACT ................................................................................................................. 92 B. INTRODUCTION .......................................................................................................... 92 C. MATERIALS AND METHODS ....................................................................................... 94 D. RESULTS AND DISCUSSION ........................................................................................ 96 E. ACKNOWLEDGEMENTS ............................................................................................... 97 F. REFERENCES .............................................................................................................. 98 V. DISTRIBUTION, DIVERSITY AND ABUNDANCE OF BEES (HYMENOPTERA: APIDAE) ON A REGIONAL SCALE: AUTECOLOGY AND COMMUNITY ECOLOGY OF BEES IN NORTHWEST ARKANSAS ........................................................................................................................