National Park Service U.S. Department of the Interior Natural Resource Stewardship and Science Catch the Buzz – Pollinator Diversity, Distribution, and Phenology in Shenandoah National Park Natural Resource Report NPS/SHEN/NRR—2017/1441 ON THIS PAGE Top: Citizen scientists (Peg Clifton, Mary O’Meara, Carolyn Smith) running pollinator traps on Skyline Drive in August 2015, Shenandoah NP. Bottom: Bee bowl trap and informational sign. Photographs courtesy of J. Rykken. ON THE COVER Bumble bee (Bombus sp.) on nodding onion (Allium cernum) in Big Meadows, Shenandoah NP. Photograph courtesy of J. Rykken. Catch the Buzz – Pollinator Diversity, Distribution, and Phenology in Shenandoah National Park Natural Resource Report NPS/SHEN/NRR—2017/1441 Jessica J. Rykken Museum of Comparative Zoology Harvard University 26 Oxford Street Cambridge, MA 02155 May 2017 U.S. Department of the Interior National Park Service Natural Resource Stewardship and Science Fort Collins, Colorado The National Park Service, Natural Resource Stewardship and Science office in Fort Collins, Colorado, publishes a range of reports that address natural resource topics. These reports are of interest and applicability to a broad audience in the National Park Service and others in natural resource management, including scientists, conservation and environmental constituencies, and the public. The Natural Resource Report Series is used to disseminate comprehensive information and analysis about natural resources and related topics concerning lands managed by the National Park Service. The series supports the advancement of science, informed decision-making, and the achievement of the National Park Service mission. 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This report is available in digital format from the National Park Service Data Store, and the Natural Resource Publications Management website (http://www.nature.nps.gov/publications/nrpm/). To receive this report in a format that is optimized to be accessible using screen readers for the visually or cognitively impaired, please email [email protected]. Please cite this publication as: Rykken, J. J. 2017. Catch the buzz – pollinator diversity, distribution, and phenology in Shenandoah National Park. Natural Resource Report NPS/SHEN/NRR—2017/1441. National Park Service, Fort Collins, Colorado. NPS 134/138251, May 2017 ii Contents Page Figures.................................................................................................................................................... v Tables .................................................................................................................................................... vi Appendices ............................................................................................................................................ vi Abstract ................................................................................................................................................ vii Acknowledgments .................................................................................................................................. x Introduction ............................................................................................................................................ 1 Methods .................................................................................................................................................. 3 Study area ....................................................................................................................................... 3 Site selection and timing of collections .......................................................................................... 3 Sampling techniques for pollinators ............................................................................................. 11 Sample processing and specimen identification ........................................................................... 11 Data analysis ................................................................................................................................. 12 Techniques for outreach and education ........................................................................................ 12 Results .................................................................................................................................................. 13 Bee and syrphid fly diversity ........................................................................................................ 13 Comparison between sampling methods and habitats .................................................................. 18 Pollinator floral associations ........................................................................................................ 21 Monitoring sites and pollinator phenology ................................................................................... 22 Phenology ..................................................................................................................................... 24 Discussion ............................................................................................................................................ 26 Shenandoah’s pollinator diversity ................................................................................................ 26 Bees ......................................................................................................................................... 26 Syrphid flies............................................................................................................................. 28 Efficacy of sampling methods ...................................................................................................... 29 Habitat and floral associations ...................................................................................................... 30 Pollinator phenology .................................................................................................................... 31 Threats to pollinators and the need for monitoring ...................................................................... 32 Educating park staff and visitors about Shenandoah’s pollinators ............................................... 33 iii Contents (continued) Page Conclusions and Recommendations .................................................................................................... 34 Literature Cited .................................................................................................................................... 35 iv Figures Page Figure 1. Examples of syrphid fly diversity in Shenandoah NP. .......................................................viii Figure 2. Examples of bee diversity in Shenandoah NP. ..................................................................... ix Figure 3a. Approximate locations for sampling sites 1-19 plus two monitoring sites (N1, N2) located in the North District of Shenandoah NP ............................................................................. 4 Figure 3b. Approximate locations for sampling sites 20-79 plus two monitoring sites (C1, C2) located in the Central District of Shenandoah NP .................................................................. 5 Figure 3c. Approximate locations for sampling sites 80-98 plus two monitoring sites (S1, S2) located in the South District of Shenandoah NP ............................................................................. 6 Figure 4. Twenty-six genera of bees collected in Shenandoah NP in decreasing order of abundance.. .......................................................................................................................................... 14 Figure 5. Twenty-nine genera of syrphid flies collected in Shenandoah NP in decreasing order of abundance. .............................................................................................................................. 14 Figure 6. Comparison of observed and estimated absolute species richness for bees and syrphid flies, using Chao 1 species richness estimator ........................................................................ 15 Figure 7. Comparison of trapping methods for bees and syrphid flies in Shenandoah NP. ............... 19 Figure 8. Comparison of total abundance and species richness across four habitats in Shenandoah NP for bees and syrphid flies. .......................................................................................... 20 Figure 9. Rarefaction curves for total numbers of bee or