Landesanstalt für Bienenkunde

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Same data, different analysts: variation in effect sizes due to analytical decisions in ecology and evolutionary biology
(2025) Gould, Elliot; Berauer, Bernd J.; Ernst, Ulrich Rainer; Zitomer, Rachel A.; Gould, Elliot; School of Agriculture Food and Ecosystem Sciences, University of Melbourne, Grattan Street, 3010, Parkville, Victoria, Australia; Fraser, Hannah S.; School of Historical and Philosophical Studies, University of Melbourne, Grattan Street, 3010, Parkville, Victoria, Australia; Parker, Timothy H.; Department of Biology, Whitman College, 345 Boyer Ave, 99362, Walla Walla, WA, USA; Nakagawa, Shinichi; School of Biological, Earth & Environmental Sciences, University of New South Wales, 2052, Sydney, NSW, Australia; Griffith, Simon C.; School of Natural Sciences, Macquarie University, Balaclava Rd, Macquarie Park, 2109, Sydney, NSW, Australia; Vesk, Peter A.; School of Agriculture Food and Ecosystem Sciences, University of Melbourne, Grattan Street, 3010, Parkville, Victoria, Australia; Fidler, Fiona; School of Historical and Philosophical Studies, University of Melbourne, Grattan Street, 3010, Parkville, Victoria, Australia; Hamilton, Daniel G.; School of Public Health and Preventive Medicine, Monash University, 750 Collins Street, 3008, Docklands, VIC, Australia; Abbey-Lee, Robin N.; Länsstyrelsen Östergötland, Östgötagatan 3, 58186, Linköping, Sweden; Abbott, Jessica K.; Biology Department, Lund University, Sölvegatan 37, 22362, Lund, Sweden; Aguirre, Luis A.; Department of Biology, University of Massachusetts, 1 Campus Center Way, 01003, Amherst, MA, USA; Alcaraz, Carles; Marine and Continental Waters, IRTA, Carretera Poble Nou Km 5.5, 43540 La Ràpita, Catalonia, Spain; Aloni, Irith; Department of Life Sciences, Ben Gurion University of the Negev, P.O.Box 653, 84105, Beer Sheva, Israel; Altschul, Drew; Department of Psychology, The University of Edinburgh, 7 George Square, EH9 1HB, Edinburgh, UK; Arekar, Kunal; Centre for Ecological Sciences, Indian Institute of Science, Indian Institute of Science, 560012, Bengaluru, Karnataka, India; Atkins, Jeff W.; Southern Research Station, USDA Forest Service, PO Box 700, 29809, New Ellenton, SC, USA; Atkinson, Joe; Center for Ecological Dynamics in a Novel Biosphere (ECONOVO), Department of Biology, Aarhus University, Ny Munkegade 114-116, 8000, Aarhus C, Denmark; Baker, Christopher M.; School of Mathematics and Statistics, University of Melbourne, 3052, Parkville, VIC, Australia; Barrett, Meghan; Biology, Indiana University Purdue University Indianapolis, 420 University Blvd, 46202, Indianapolis, IN, USA; Bell, Kristian; School of Life and Environmental Sciences, Deakin University, 221 Burwood Highway, 3125, Burwood, VIC, Australia; Bello, Suleiman Kehinde; Department of Arid Land Agriculture, King Abdulaziz University, 80200, Jeddah, Kingdom of Saudi Arabia; Beltrán, Iván; Department of Biological Sciences, Macquarie University, 205ACR Culloden Road, 2113, Macquarie Park, New South Wales, Australia; Berauer, Bernd J.; Department of Plant Ecology, University of Hohenheim, Institute of Landscape and Plant Ecology, Ottilie-Zeller-Weg, 70599, Stuttgart, Germany; Bertram, Michael Grant; Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, Skogsmarksgränd 17, SE-907 36, Umeå, Sweden; Billman, Peter D.; Department of Ecology and Evolutionary Biology, University of Connecticut, 75 N. Eagleville Rd, 06226, Storrs, CT, USA; Blake, Charlie K.; STEM Center, Southern Illinois University Edwardsville, 1 Hairpin Dr, 62026, Edwardsville, IL, USA; Blake, Shannon; University of Guelph, 50 Stone Road East, N1G 2W1, Guelph, Ontario, Canada; Bliard, Louis; Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057, Zürich, Switzerland; Bonisoli-Alquati, Andrea; Department of Biological Sciences, California State Polytechnic University, Pomona, USA; Bonnet, Timothée; Centre d’Études Biologiques de Chizé, UMR 7372, Université de la Rochelle - Centre National de la Recherche Scientifique, 405 route de Prissé la Charrière, 79360, Villiers en Bois, France; Bordes, Camille Nina Marion; Faculty of Life Sciences, Bar Ilan University, Ramat Gan 529000, Israel; Bose, Aneesh P. H.; Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, Skogsmarksgränd 17, SE-907 36, Umeå, Sweden; Botterill-James, Thomas; School of Natural Sciences, University of Tasmania, TAS, Private Bag 55, 7001, Hobart, Australia; Boyd, Melissa Anna; Whitebark Institute, 3399 Main Street, Suite W5, 93546, Mammoth Lakes, CA, USA; Boyle, Sarah A.; Department of Biology, Rhodes College, 2000 N. 38112, Parkway, Memphis, TN, USA; Bradfer-Lawrence, Tom; Centre for Conservation Science, RSPB, 2 Lochside View, EH12 9DH, Edinburgh, UK; Bradham, Jennifer; Environmental Studies, Wofford College, 429 N. Church St, 29303, Spartanburg, SC, USA; Brand, Jack A.; Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, Skogsmarksgränd 17, SE-907 36, Umeå, Sweden; Brengdahl, Martin I.; IFM Biology, Linköping University, 581 83, Linköping, Sweden; Bulla, Martin; Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Czech Republic, Kamýcká 129, 165 00, Praha - Suchdol, Czech Republic; Bussière, Luc; Biological and Environmental Sciences & Gothenburg Global Biodiversity Centre, University of Gothenburg, Medicinaregatan 7B, SE-413 90, Gothenburg, Sweden; Camerlenghi, Ettore; School of Biological Sciences, Monash University, Rainforest Walk 25, Clayton, Victoria, Australia; Campbell, Sara E.; Ecology and Evolutionary Biology, University of Tennessee Knoxville, 569 Dabney Hall, 37996, Knoxville, TN, USA; Campos, Leonardo L. F.; Departamento de Ecologia e Zoologia, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, UFSC, Campus Universitário - Córrego Grande Florianópolis – SC; CEP, 88040-900, Florianópolis, Brazil; Caravaggi, Anthony; School of Biological and Forensic Sciences, University of South Wales, The Alfred Russel Wallace Building, 9 Graig Fach, CF37 4BB, Glyntaff, Pontypridd, UK; Cardoso, Pedro; Centre for Ecology, Evolution and Environmental Changes (cE3c) &, CHANGE - Global Change and Sustainability Institute, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisbon, Portugal; Carroll, Charles J. W.; Forest and Rangeland Stewardship, Colorado State University, 1472 Campus Delivery, 80523-1472, Fort Collins, CO, USA; Catanach, Therese A.; Department of Ornithology, Academy of Natural Sciences of Drexel University, 1900 Benjamin Franklin Parkway, 19096, Philadelphia, PA, USA; Chen, Xuan; Salisbury University, 1101 Camden Ave, 21801, Biology, Salisbury, MD, USA; Chik, Heung Ying Janet; Groningen Institute for Evolutionary Life Sciences, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, Netherlands; Choy, Emily Sarah; Department of Biology, McMaster University, 1280 Main Street West, L8S 4K1, Hamilton, ON, Canada; Christie, Alec Philip; Department of Zoology, University of Cambridge, Downing St, CB2 3EJ, Cambridge, UK; Chuang, Angela; Entomology and Nematology, University of Florida, 700 Experiment Station Rd, 33850, Lake Alfred, FL, USA; Chunco, Amanda J.; Environmental Studies, Elon University, McMichael Science Building, 2625 Campus Box, 27244, Elon, NC, USA; Clark, Bethany L.; BirdLife International, David Attenborough Building, Pembroke Street, CB2 3QZ, Cambridge, UK; Contina, Andrea; School of Integrative Biological and Chemical Sciences, The University of Texas Rio Grande Valley, One West University Boulevard, 78520, Brownsville, TX, USA; Covernton, Garth A.; Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks St, M5S 3B2, Toronto, ON, Canada; Cox, Murray P.; Department of Statistics, University of Auckland, Auckland, New Zealand; Cressman, Kimberly A.; LLC, Catbird Stats, PO Box 2018, 39553, Gautier, MS, USA; Crotti, Marco; School of Biodiversity, One Health & Veterinary Medicine, University of Glasgow, University Avenue, G12 8QQ, Glasgow, UK; Crouch, Connor Davidson; School of Forestry, Northern Arizona University, 200 E Pine Knoll Dr. 86001, Flagstaff, AZ, USA; D’Amelio, Pietro B.; Department of Behavioural Neurobiology, Max Planck Institute for Biological Intelligence, Eberhard-Gwinner-Strasse, 82319, Seewiesen, Oberbayern, Germany; de Sousa, Alexandra Allison; School of Sciences: Center for Health and Cognition, Bath Spa University, BA2 9BN, Newton Park, Bath, UK; Döbert, Timm Fabian; Department of Biological Sciences, University of Alberta, T6G 2R3, Edmonton, AB, Canada; Dobler, Ralph; Applied Zoology, Zellescher Weg 20b, 01217, Dresden, TUDresden, Germany; Dobson, Adam J.; School of Molecular Biosciences, College of Medical Veterinary & Life Sciences, University of Glasgow, G12 8Qq, Glasgow, UK; Doherty, Tim S.; School of Life and Environmental Sciences, The University of Sydney, 2006, Camperdown, NSW, Australia; Drobniak, Szymon Marian; Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387, Krakow, Poland; Duffy, Alexandra Grace; Biology Department, Brigham Young University, 4102 Life Science Building, Provo, UT, USA; Duncan, Alison B.; Institute of Evolutionary Sciences Montpellier, University of Montpellier, CNRS, IRD, Montpellier, France; Dunn, Robert P.; Baruch Marine Field Laboratory, University of South Carolina, 2306 Crabhaul Rd, 29440, Georgetown, SC, USA; Dunning, Jamie; Department of Life Sciences, Imperial College London, Buckhurst road, SL5 7PY, Berkshire, UK; Dutta, Trishna; European Forest Institute, Platz d. Vereinten Nationen 7, 53113, Bonn, Germany; Eberhart-Hertel, Luke; Department of Ornithology, Max Planck Institute for Biological Intelligence, Eberhard-Gwinner Str. 7, 82319, Seewiesen, Germany; Elmore, Jared Alan; Forestry and Environmental Conservation, National Bobwhite and Grassland Initiative, Clemson University, 243 Lehotsky Hall, 29634, Clemson, SC, USA; Elsherif, Mahmoud Medhat; Department of Psychology and Vision Science, University of Birmingham, 52 Pritchatts Road. Edgbaston, B15 2TT, Baily Thomas GrantBirmingham, UK; English, Holly M.; School of Biology and Environmental Science, University College Dublin, Dublin 4, D04 V1W8, Belfield, Ireland; Ensminger, David C.; Department of Biological Sciences, San José State University, 129 S 10th Street, 95112, San Jose, CA, USA; Ernst, Ulrich Rainer; Apicultural State Institute, University of Hohenheim, Erna-Hruschka-Weg 6, 70599, Stuttgart, Germany; Ferguson, Stephen M.; Department of Biology, St. Norbert College, 100 Grant St, 54115, De Pere, WI, USA; Fernandez-Juricic, Esteban; Department of Biological Sciences, Purdue University, 915 W. State Street, 47907, West Lafayette, IN, USA; Ferreira-Arruda, Thalita; Biodiversity, Faculty of Forest Sciences and Forest Ecology, University of Göttingen, Macroecology & BiogeographyBüsgenweg 1, 37077, Göttingen, Germany; Fieberg, John; Department of Fisheries, Wildlife and Conservation Biology, University of Minnesota-Twin Cities, 135 Skok Hall, 2003 Upper Buford Circle, 55108, St. Paul, MN, USA; Finch, Elizabeth A.; CABI, Bakeham Lane, Egham, Surrey, UK; Fiorenza, Evan A.; Department of Ecology and Evolutionary Biology, School of Biological Sciences, University of California, 321 Steinhaus Hall, 92697, IrvineIrvine, CA, USA; Fisher, David N.; School of Biological Sciences, University of Aberdeen, King Street, AB244FX, Aberdeen, UK; Fontaine, Amélie; Department of Natural Resource Sciences, McGill University, 21111 Lakeshore Rd, Ste Anne-de-Bellevue, H9X 3V9, Montreal, QC, Canada; Forstmeier, Wolfgang; Department of Ornithology, Max Planck Institute for Biological Intelligence, Eberhard-Gwinner Str. 7, 82319, Seewiesen, Germany; Fourcade, Yoan; Institute of Ecology and Environmental Sciences (iEES), Univ. Paris-Est Creteil, 61 avenue du Général de Gaulle, 94010, Créteil, France; Frank, Graham S.; Department of Forest Ecosystems and Society, Oregon State University, 321 Richardson Hall, 97331, Corvallis, OR, USA; Freund, Cathryn A.; Wake Forest University, 1834 Wake Forest Road, 27109, Winston Salem, NC, USA; Fuentes-Lillo, Eduardo; Laboratorio de Invasiones Biológicas (LIB), Instituto de Ecología y Biodiversidad, Victoria 631, Concepción, Chile; Gandy, Sara L.; Institute for Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, G12 8QQ, Glasgow, UK; Gannon, Dustin G.; Department of Forest Ecosystems and Society, College of Forestry, Oregon State University, 97333, Corvallis, OR, USA; García-Cervigón, Ana I.; Biodiversity and Conservation Area, Rey Juan Carlos University, C/ Tulipán s/n, 28933, Móstoles, Madrid, Spain; Garretson, Alexis C.; Graduate School of Biomedical Sciences, Tufts University, 136 Harrison Ave #813, 02111, Boston, MA, USA; Ge, Xuezhen; Department of Integrative Biology, University of Guelph, 50 Stone Rd E, N1G 2W1, Guelph, ON, Canada; Geary, William L.; School of Life and Environmental Sciences (Burwood Campus), Deakin University, Geelong, Victoria, Australia; Géron, Charly; CNRS, University of Rennes, 263 Avenue du Général Leclerc, 35042, Rennes, France; Gilles, Marc; Department of Behavioural Ecology, Bielefeld University, Konsequenz 45, 33615, Bielefeld, Germany; Girndt, Antje; Fakultät für Biologie, Arbeitsgruppe Evolutionsbiologie, Universität Bielefeld, Morgenbreede 45, 33615, Bielefeld, Germany; Gliksman, Daniel; Chair of Meteorology, Institute for Hydrology and Meteorology, Faculty of Environmental Sciences, Technische Universität Dresden, Pienner Str. 23, 01737, Tharandt, Germany; Goldspiel, Harrison B.; Department of Wildlife, Fisheries, and Conservation Biology, University of Maine, 5755 Nutting Hall, Room 210, 04469-5755, Orono, ME, USA; Gomes, Dylan G. E.; Department of Biological Sciences, Boise State University, 1910 W University Dr, 83725, Boise, ID, USA; Good, Megan Kate; School of Agriculture, Food and Ecosystem Sciences, The University of Melbourne, Grattan Street, 3010, Parkville, Victoria, Australia; Goslee, Sarah C.; Pastures Systems and Watershed Management Research Unit, USDA Agricultural Research Service, USDA-ARS PSWMRU, Bldg. 3702 Curtin Road, 16802, University Park, PA, USA; Gosnell, J. Stephen; Department of Natural Sciences, Baruch College, City University of New York, 17 Lexington Avenue, 10010, New York, NY, USA; Grames, Eliza M.; Department of Biological Sciences, Binghamton University, 4400 Vestal Parkway East, 13902, Binghamton, NY, USA; Gratton, Paolo; Dipartimento di Biologia, Università di Roma “Tor Vergata”, Via Cracovia, 1, 00133, Rome, Italy; Grebe, Nicholas M.; Department of Anthropology, University of Michigan, 1085 S. University Ave, 48109, Ann Arbor, MI, USA; Greenler, Skye M.; College of Forestry, Oregon State University, 3100 SW Jefferson Way, 97333, Corvallis, OR, USA; Griffioen, Maaike; University of Antwerp, Universiteitsplein 1, 2610, Wilrijk, België, Belgium; Griffith, Daniel M.; Earth & Environmental Sciences, Wesleyan University, 45 Wyllys Ave, 06459, Middletown, CT, USA; Griffith, Frances J.; Department of Psychiatry, Yale School of Medicine, Yale University, 389 Whitney Ave, 06511, New Haven, CT, USA; Grossman, Jake J.; Biology Department and Environmental Studies Department, St. Olaf College, 1520 St Olaf Ave, 55057, Northfield, MN, USA; Güncan, Ali; Department of Plant Protection, Faculty of Agriculture, Department of Plant Protection, Faculty of Agriculture, Ordu University, Ordu University, 52200, Altinordu/Ordu, Turkey; Haesen, Stef; Department of Earth and Environmental Sciences, KU Leuven, Celestijnenlaan 200E, 3001, Leuven, Belgium; Hagan, James G.; Department of Marine Sciences, University of Gothenburg, Box 461, SE-40530, Gothenburg, Sweden; Hager, Heather A.; Department of Biology, Wilfrid Laurier University, 75 University Ave West, N2L 3C5, Waterloo, Ontario, Canada; Harris, Jonathan Philo; Natural Resource Ecology and Management, Iowa State University, 2310 Pammel Dr, 50011, Ames, IA, USA; Harrison, Natasha Dean; School of Biological Sciences, University of Western Australia, 35 Stirling Highway, 6009, Crawley, Western Australia, Australia; Hasnain, Sarah Syedia; Department of Biological Sciences, Middle East Technical University, Üniversiteler Mahallesi, Dumlupınar Bulvarı No: 1, 06800, Çankaya/Ankara, Turkey; Havird, Justin Chase; Dept. of Integrative Biology, University of Texas at Austin,2415 Speedway #C0930, Austin, TX, USA; Heaton, Andrew J.; Grand Bay National Estuarine Research Reserve, 6005 Bayou Heron Rd, 39562, Moss Point, MS, USA; Herrera-Chaustre, María Laura; Universidad de los Andes, Carrera 1 # 18A-12, Bogotá, Colombia; Howard, Tanner J.; School of Agriculture Food and Ecosystem Sciences, University of Melbourne, Grattan Street, 3010, Parkville, Victoria, Australia; Hsu, Bin-Yan; Department of Biology, University of Turku, Turun Yliopisto, FI-20014, Turku, Finland; Iannarilli, Fabiola; Department of Fisheries, Wildlife and Conservation Biology, University of Minnesota-Twin Cities, 135 Skok Hall, 2003 Upper Buford Circle, 55108, St. Paul, MN, USA; Iranzo, Esperanza C.; Instituto de Ciencia Animal. Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Campus Isla Teja s/n, Valdivia, Chile; Iverson, Erik N. K.; Department of Integrative Biology, The University of Texas at Austin, 2415 Speedway #C0930, 78712, Austin, Texas, USA; Jimoh, Saheed Olaide; Department of Botany, University of Wyoming, 82071, Laramie, WY, USA; Johnson, Douglas H.; Department of Fisheries, Wildlife and Conservation Biology, University of Minnesota-Twin Cities, 135 Skok Hall, 2003 Upper Buford Circle, 55108, St. Paul, MN, USA; Johnsson, Martin; Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, Box 7023, 750 07, Uppsala, Sweden; Jorna, Jesse; Department of Biology, Brigham Young University, Brigham Young University, Brigham Young University, 84602, Provo, UT, USA; Jucker, Tommaso; School of Biological Sciences, University of Bristol, 24 Tyndall Avenue, BS8 1TQ, Bristol, UK; Jung, Martin; International Institute for Applied Systems Analysis (IIASA), Schlossplatz 1, A-2361, Laxenburg, Austria; Kačergytė, Ineta; Department of Ecology, Swedish University of Agricultural Sciences, Ulls Väg 16, 750 07, Uppsala, Sweden; Kaltz, Oliver; Université de Montpellier, ISEM, University of Montpellier, CNRS, EPHE, 34000, Montpellier, IRD, France; Ke, Alison; Department of Wildlife, Fish, and Conservation Biology, University of California, 1 Shields Ave, 95616, DavisDavis, CA, USA; Kelly, Clint D.; Département des Sciences biologiques, Université du Québec à Montréal, 141 Avenue du Président-Kennedy, H2X 1Y4, Montréal, Québec, Canada; Keogan, Katharine; Institute of Evolutionary Biology, University of Edinburgh, King’s Buildings, EH9 3JW, Edinburgh, UK; Keppeler, Friedrich Wolfgang; Center for Limnology, University of Wisconsin - Madison, 680 N Park St, 53706, Madison, WI, USA; Killion, Alexander K.; Center for Biodiversity and Global Change, Yale University, 165 Prospect St, 06511, New Haven, CT, USA; Kim, Dongmin; Department of Ecology, Evolution, and Behavior, University of Minnesota, Ecology Building, 1987 Upper Buford Cir, 55108, St. PaulSt Paul, MN, USA; Kochan, David P.; Institute of Environment and Department of Biological Sciences, Florida International University, 3000 NE 151st St, 33181, North Miami, FL, USA; Korsten, Peter; Department of Life Sciences, Aberystwyth University, SY23 3DA, Penglais, Aberystwyth, UK; Kothari, Shan; Institut de recherche en biologie végétale, Université de Montréal, 4101, H1X 2B2, Sherbrooke St E, Montréal, Québec, Canada; Kuppler, Jonas; Institute of Evolutionary Ecology and Conservation Genomics, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany; Kusch, Jillian M.; Department of Biology, Memorial University of Newfoundland, 45 Arctic Ave, A1C5S7, St John’s NL, Canada; Lagisz, Malgorzata; Evolution & Ecology Research Centre, School of Biological, Earth & Environmental Sciences, University of New South Wales, UNSW Sydney, High Street 2052, Kensington, NSW, Australia; Lalla, Kristen Marianne; Department of Natural Resource Sciences, McGill University, 21111 Lakeshore Rd, Ste Anne-de-Bellevue, H9X 3V9, Montreal, QC, Canada; Larkin, Daniel J.; Department of Fisheries, Wildlife and Conservation Biology, University of Minnesota-Twin Cities, 135 Skok Hall, 2003 Upper Buford Circle, 55108, St. Paul, MN, USA; Larson, Courtney L.; The Nature Conservancy, 258 Main Street, 82520, Lander, WY, USA; Lauck, Katherine S.; Department of Wildlife, Fish, and Conservation Biology, University of California, 1 Shields Ave, 95616, DavisDavis, CA, USA; Lauterbur, M. Elise; Ecology and Evolutionary Biology, University of Arizona, 1041 E Lowell St, 85721, Tucson, AZ, USA; Law, Alan; Biological and Environmental Sciences, University of Stirling, Cottrell Building, FK9 4LA, Stirling, UK; Léandri-Breton, Don-Jean; Department of Natural Resource Sciences, McGill University, 21111 Lakeshore Rd, Ste Anne-de-Bellevue, H9X 3V9, Montreal, QC, Canada; Lembrechts, Jonas J.; Department of Biology, University of Antwerp, Universiteitsplein 1, 2610, Wilrijk, Belgium; L’Herpiniere, Kiara; School of Natural Sciences, Macquarie University, Balaclava Rd, Macquarie Park, 2109, Sydney, NSW, Australia; Lievens, Eva J. P.; Aquatic Ecology and Evolution Group, Limnological Institute, University of Konstanz, Mainaustraße 252, 78464, Konstanz, Germany; de Lima, Daniela Oliveira; Campus Cerro Largo, Universidade Federal da Fronteira Sul, Rua Jacob Haupenthal, 158097900-000, Cerro Largo, RS, CEP, Brazil; Lindsay, Shane; School of Psychology and Social Work, University of Hull, Cottingham Rd, HU6 7RX, Hull, UK; Luquet, Martin; UMR 1224, ECOBIOP, Université de Pau et des Pays de l′Adour, 173 Route de Saint-Jean-de-Luz, 64310, Saint-Pée-sur-Nivelle, France; MacLeod, Ross; School of Biological & Environmental Sciences, Liverpool John Moores University, James Parsons Building, Byrom Street, L3 3AF, Liverpool, UK; Macphie, Kirsty H.; Institute of Ecology and Evolution, University of Edinburgh, The University of Edinburgh, King’s Buildings, Charlotte Auerbach Road, EH9 3FL, Edinburgh, UK; Magellan, Kit; Phnom Penh, Cambodia; Mair, Magdalena M.; Statistical Ecotoxicology, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Universitätsstraße 30, 95440, Bayreuth, Germany; Malm, Lisa E.; Ecology and Environmental Science, Umeå University, Linnaeus väg 6, 907 36, Umeå, Sweden; Mammola, Stefano; Molecular Ecology Group (MEG), Water Research Institute (IRSA), National Research Council of Italy (CNR), 28922, Corso Tonolli 50, Verbania, Italy; Mandeville, Caitlin P.; Department of Natural History, Norwegian University of Science and Technology, Høgskoleringen 1, 7034, Trondheim, Norway; Manhart, Michael; Center for Advanced Biotechnology and Medicine, Rutgers University Robert Wood Johnson Medical School, 679 Hoes Lane West, 08854, Piscataway, NJ, USA; Manrique-Garzon, Laura Milena; Departamento de Ciencias Biológicas, Universidad de los Andes, Carrera 1 Nº 18A - 12, 111711, Bogotá, Bogotá D. C, Colombia; Mäntylä, Elina; Department of Biology, University of Turku, Turun Yliopisto, FI-20014, Turku, Finland; Marchand, Philippe; Institut de recherche sur les forêts, Université du Québec en Abitibi-Témiscamingue, 445 Boulevard de l’Université, J9X 5E4, Rouyn-Noranda, QC, Canada; Marshall, Benjamin Michael; Biological and Environmental Sciences, University of Stirling, Cottrell Building, FK9 4LA, Stirling, UK; Martin, Charles A.; Université du Québec à Trois-Rivières, 3351, boulevard des Forges, G8Z 4M3, Trois-Rivières (Québec), Canada; Martin, Dominic Andreas; Institute of Plant Sciences, University of Bern, Altenbergrain 21, 3013, Bern, Switzerland; Martin, Jake Mitchell; Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, Skogsmarksgränd 17, SE-907 36, Umeå, Sweden; Martinig, April Robin; School of Biological, Earth and Environmental Sciences, University of New South Wales, Randwick, 2052, Sydney, NSW, Australia; McCallum, Erin S.; Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, Skogsmarksgränd 17, SE-907 36, Umeå, Sweden; McCauley, Mark; Whitney Laboratory for Marine Bioscience, University of Florida, 9505 N Ocean Shore Blvd, St. Augustine, 32080, Gainesville, FL, USA; McNew, Sabrina M.; Ecology and Evolutionary Biology, University of Arizona, 1041 E Lowell St, 85721, Tucson, AZ, USA; Meiners, Scott J.; Biological Sciences, Eastern Illinois University, 600 Lincoln Avenue, 61920, Charleston, IL, USA; Merkling, Thomas; Centre d’Investigations Clinique Plurithématique - Institut Lorrain du Coeur et des Vaisseaux, Université de Lorraine, Inserm1433 CIC-P CHRU de Nancy, bâtiment Louis Mathieu - 5, rue du Morvan - 54500, Vandoeuvre-les-nancy, France; Michelangeli, Marcus; Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, Skogsmarksgränd 17, SE-907 36, Umeå, Sweden; Moiron, Maria; Evolutionary biology department, Bielefeld University, Bielefeld University, Konsequenz 45, 33615, Bielefeld, Germany; Moreira, Bruno; Department of Ecology and global change, Centro de Investigaciones sobre Desertificación, Consejo Superior de Investigaciones Cientificas (CIDE-CSIC/UV/GV), Carretera CV-315 km 10,7, 46113, Moncada (Valencia), Spain; Mortensen, Jennifer; Department of Biological Sciences, University of Arkansas, 850 W. Dickson Street SCEN601, 72701, Fayetteville, AR, USA; Mos, Benjamin; School of the Environment, Faculty of Science, The University of Queensland, The University of Queensland, 4072, Brisbane, QLD, Australia; Muraina, Taofeek Olatunbosun; Department of Animal Health and Production, Oyo State College of Agriculture and Technology, Igbo-Ora 201103, Oyo State, Nigeria; Murphy, Penelope Wrenn; Department of Forest & Wildlife Ecology, University of Wisconsin-Madison, 1630 Linden Drive, 53706, Madison, WI, USA; Nelli, Luca; School of Biodiversity, One Health & Veterinary Medicine, University of Glasgow, University Avenue, G12 8QQ, Glasgow, UK; Niemelä, Petri; Organismal and Evolutionary Biology Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, 00014, Helsinki, Finland; Nightingale, Josh; South Iceland Research Centre, University of Iceland, Lindarbraut 4, 840, Laugarvatn, Iceland; Nilsonne, Gustav; Department of Clinical Neuroscience, Karolinska Institutet, Nobels väg 9, 171 77, Stockholm, Sweden; Nolazco, Sergio; School of Biological Sciences, Monash University, Rainforest Walk 25, Clayton, Victoria, Australia; Nooten, Sabine S.; Animal Ecology and Tropical Biology, University of Würzburg, Biocenter-Am Hubland, 97074, Würzburg, Germany; Novotny, Jessie Lanterman; Hiram College, 11700 Dean St, 44234, Biology, Hiram, OH, USA; Olin, Agnes Birgitta; Department of Aquatic Resources, Swedish University of Agricultural Sciences, Almas allé 5, 756 51, Uppsala, Sweden; Organ, Chris L.; Department of Earth Sciences, Montana State University, 59717, Bozeman, MT, USA; Ostevik, Kate L.; Department of Evolution, Ecology, and Organismal Biology, University of California, 900 University Ave, 92521, RiversideRiverside, CA, USA; Palacio, Facundo Xavier; Sección Ornitología, Universidad Nacional de La Plata, Paseo del Bosqur s/n, La Plata, B1900FWA, Buenos Aires, Argentina; Paquet, Matthieu; Department of Ecology, Swedish University of Agricultural Sciences, Ulls Väg 16, 750 07, Uppsala, Sweden; Parker, Darren James; Bangor University, Bangor University, Deiniol Road, LL57 2UW, Bangor, UK; Pascall, David J.; MRC Biostatistics Unit, University of Cambridge, East Forvie Building, Forvie Site, Robinson Way, CB2 0SR, Cambridge, UK; Pasquarella, Valerie J.; Harvard Forest, Harvard University, 324 N Main St, 01366, Petersham, MA, USA; Paterson, John Harold; Department of Marine Sciences, University of Gothenburg, Box 461, SE-40530, Gothenburg, Sweden; Payo-Payo, Ana; Departamento de Biodiversidad, Ecología y Evolución, Universidad Complutense de Madrid, C. de José Antonio Novais, 12, 28040, Madrid, Spain; Pedersen, Karen Marie; Biology Department, Technische Universität Darmstadt, Schnittspahnstraße 3, 64287, Darmstadt, Germany; Perez, Grégoire; UMR 1309, ASTRE, CIRAD, Campus international de Baillarguet, 34398, Montpellier, France; Perry, Kayla I.; Department of Entomology, The Ohio State University, 1680 Madison Ave, 44691, Wooster, OH, USA; Pottier, Patrice; Evolution & Ecology Research Centre, School of Biological, Earth & Environmental Sciences, University of New South Wales, UNSW Sydney, High Street 2052, Kensington, NSW, Australia; Proulx, Michael J.; Department of Psychology, University of Bath, 10 West, BA2 7AY, Bath, UK; Proulx, Raphaël; Chaire de recherche en intégrité écologique, Université du Québec à Trois-Rivières, 3351 Boul. 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Although variation in effect sizes and predicted values among studies of similar phenomena is inevitable, such variation far exceeds what might be produced by sampling error alone. One possible explanation for variation among results is differences among researchers in the decisions they make regarding statistical analyses. A growing array of studies has explored this analytical variability in different fields and has found substantial variability among results despite analysts having the same data and research question. Many of these studies have been in the social sciences, but one small “many analyst” study found similar variability in ecology. We expanded the scope of this prior work by implementing a large-scale empirical exploration of the variation in effect sizes and model predictions generated by the analytical decisions of different researchers in ecology and evolutionary biology. We used two unpublished datasets, one from evolutionary ecology (blue tit, Cyanistes caeruleus , to compare sibling number and nestling growth) and one from conservation ecology ( Eucalyptus , to compare grass cover and tree seedling recruitment). The project leaders recruited 174 analyst teams, comprising 246 analysts, to investigate the answers to prespecified research questions. Analyses conducted by these teams yielded 141 usable effects (compatible with our meta-analyses and with all necessary information provided) for the blue tit dataset, and 85 usable effects for the Eucalyptus dataset. We found substantial heterogeneity among results for both datasets, although the patterns of variation differed between them. For the blue tit analyses, the average effect was convincingly negative, with less growth for nestlings living with more siblings, but there was near continuous variation in effect size from large negative effects to effects near zero, and even effects crossing the traditional threshold of statistical significance in the opposite direction. In contrast, the average relationship between grass cover and Eucalyptus seedling number was only slightly negative and not convincingly different from zero, and most effects ranged from weakly negative to weakly positive, with about a third of effects crossing the traditional threshold of significance in one direction or the other. However, there were also several striking outliers in the Eucalyptus dataset, with effects far from zero. For both datasets, we found substantial variation in the variable selection and random effects structures among analyses, as well as in the ratings of the analytical methods by peer reviewers, but we found no strong relationship between any of these and deviation from the meta-analytic mean. In other words, analyses with results that were far from the mean were no more or less likely to have dissimilar variable sets, use random effects in their models, or receive poor peer reviews than those analyses that found results that were close to the mean. The existence of substantial variability among analysis outcomes raises important questions about how ecologists and evolutionary biologists should interpret published results, and how they should conduct analyses in the future.
Wirksamkeit, Nebenwirkung und Verteilung von Lithiumchlorid: ein neuer Wirkstoff zur Behandlung von Varroa destructor bei Honigbienenvölkern (Apis mellifera)
(2024) Rein, Carolin Vanessa; Rosenkranz, Peter
Honigbienen sind unverzichtbare Bestäuber sowohl für unser Ökosystem als auch für die Landwirtschaft. Die weltweit verbreitete ektoparasitische Milbe Varroa destructor stellt seit Jahrzehnten das größte Problem für Honigbienen und die Imkerei dar und gilt zweifellos als Hauptverursacher der periodischen Völkerverluste (Genersch et al. 2010; Le Conte et al. 2010). Derzeit gibt es kein zufriedenstellendes Behandlungsverfahren, das alle Anforderungen der Imker erfüllt. Im Jahr 2018 wurde mit Lithiumchlorid (LiCl) ein neuer Wirkstoff mit varroazider Wirkung entdeckt, welcher eine sehr gute Wirksamkeit auf Varroamilben mit einer guten Verträglichkeit für adulte Bienen verbindet (Ziegelmann et al. 2018). Aufgrund der systemischen Wirkungsweise kann er zudem sehr einfach angewendet werden und bietet dadurch großes Potential für eine effektive Varroabehandlung. Im Rahmen der Dissertation wurden verschiedene Applikationsformen von LiCl zur Behandlung von Bienenvölkern getestet und Daten zur Wirksamkeit, Nebenwirkung und Verteilung des Wirkstoffes erhoben. Die gesammelten Daten sollen dazu dienen, eine fundierte Bewertung der Chancen und Risiken für ein Zulassungsverfahren zu ermöglichen und erfolgsversprechende Strategien für die Zulassung zu entwickeln. Zu diesem Zweck wurden verschiedene Feld- und Laborexperimente durchgeführt. Unter praxisnahen Freilandbedingungen führt die Applikation von LiCl zu konzentrationsabhängigen Schäden und hohen Ausräumraten der Bienenbrut. Diese Brutschäden sind von der Dauer der Fütterung und dem Larvenalter abhängig (Rein et al. 2022). Bei einer Fütterung von 25 mM LiCl überleben nur knapp 40% der Bienenbrut. Analysen der Lithium-Konzentration verschiedener Larvenstadien zeigen, dass in zwei Tage alten Larven noch kein Lithium nachgewiesen werden kann. Die Analysen der Futtersaftdrüsen haben bestätigt, dass das Sekret der Ammenbienen, mit dem die Königin und die jungen Larvenstadien gefüttert werden, weitgehend frei von Lithium ist (Rein et al. 2024). Daher sollte eine LiCl-Applikation kein Risiko für die Königin, oder die jungen Larven darstellen. In älteren Larven steigt die Lithium-Konzentration dagegen signifikant an (Rein et al. 2022). Dies ist auf die stadienspezifische Futterumstellung von reinem Futtersaft auf gemischtes Larvenfutter zurückzuführen. Hierbei wird auch eingelagertes Futter aus den umliegenden Waben beigemengt, wodurch auch zuvor eingelagertes Lithium weitergegeben werden kann. Aufgrund der schädigenden Wirkung von LiCl auf die Bienenbrut wurde eine Applikation für brutfreie Völker entwickelt und die Wirksamkeit unter Feldbedingungen getestet. Die Kombination einer brutfreien Phase durch Sperren der Königin mit der LiCl-Behandlung erzielte durchschnittliche Wirkungsgrade von 78 – 98% (Rein et al. 2024). Die höchsten Wirkungsgrade wurden erst bei einer Fütterungsdauer von > 5 Tagen erreicht, was zu Schäden bei der neu angelegten Brut nach der Brutpause führte. In Käfigversuchen, in denen jeweils eine Biene mit einer parasitierenden Milbe mit LiCl gefüttert wurde, konnten dagegen bereits nach 48 Stunden Milbenmortalitäten von über 95% erreicht werden (Rein et al. 2024). Offenbar verzögerte sich im Volk der Wirkungseintritt aufgrund des sozialen Futteraustauschs (Trophallaxis) und einem damit verbundenen Verdünnungseffekt des Wirkstoffs. Jedoch ist dieser Futteraustausch notwendig, um den Wirkstoff gleichmäßig im Volk zu verteilen und alle Milben zu erreichen. Es besteht daher weiterer Optimierungsbedarf, um die für die Zulassung notwendigen Wirkungsgrade von über 90% zu erreichen, ohne die Bienenbrut zu schädigen. Anhand von quantitativen Lithium-Analysen über ICP-OES konnte bestätigt werden, dass der Wirkstoff im Volk gleichmäßig verteilt wird. Bereits einen Tag nach der LiCl-Applikation wurden im Schnitt 93 mg/kg Lithium in den Honigblasen der Bienen nachgewiesen, unabhängig von ihrer Position im Volk (Rein et al. 2024). Analysen der Bienen-Hämolymphe zeigen, dass bereits nach einer 12-stündigen Fütterung der Bienen im Käfig ein Gleichgewicht von 5 – 8 mg/kg Lithium erreicht wird, welches zum Tod der Milbe führt (Rein et al. 2024). Das Lithium sollte daher nach einer LiCl-Applikation möglichst schnell im gesamten Volk verteilt werden und ausreichend lange im Volk zirkulieren, um möglichst in allen Bienen die für Milben tödliche Konzentration zu erreichen. Diese Konzentration sollte für etwa 48 Stunden aufrechterhalten werden, um eine Milbenmortalität von über 95% zu erreichen. Die im Rahmen der vorliegenden Dissertation durchgeführten Versuche bieten eine umfangreiche Basis für die Entwicklung einer zulassungsrelevanten Applikation. Es konnte gezeigt werden, dass Lithium eine hohe akarizide Wirkung besitzt und lediglich noch einige Optimierungen notwendig sind, um eine bessere Verteilung des Wirkstoffes und damit stabile Wirkungsgrade von über 90% bei brutfreien Völkern zu erreichen. Für brütende Völker müssen jedoch alternative Behandlungsmöglichkeiten entwickelt werden, um den Kontakt der Brut mit dem Wirkstoff zu vermeiden.
Temporal increase of Varroa mites in trap frames used for drone brood removal during the honey bee season
(2022) Odemer, Richard; Odemer, Franziska; Liebig, Gerhard; de Craigher, Doris
Varroa mites are highly attracted to drone brood of honey bees (Apis mellifera), as it increases their chance of successful reproduction. Therefore, drone brood removal with trap frames is common practice among beekeepers in Europe and part of sustainable varroa control. However, it is considered labour‐intensive, and there are doubts about the effectiveness of this measure. At present, it is mostly unknown how many mites a drone frame can carry at different times of the season, and how many mites can be removed on average if this measure is performed frequently. Therefore, we sampled a total of 262 drone frames with varying proportion of capped cells (5–100%) from 18 different apiaries. Mites were washed out from brood collected from mid‐April to mid‐July based on a standard method to obtain comparable results. We found that a drone frame carried a median of 71.5 mites, and with the removal of four trap frames, about 286 mites can be removed per colony and season. In addition, mite counts were significantly higher in June and July than in April and May (Tukey‐HSD, P < 0.05). The number of mites and the proportion of capped cells, however, were not correlated (R2 < 0.01, P < 0.05). Our results suggest that drone brood removal is effective in reducing Varroa destructor numbers in colonies, supporting the findings of previous studies on the efficacy of this measure. Although mite counts varied, we believe that increasing sample size over different seasons and locations could elucidate infestation patterns in drone brood and ultimately improve drone brood removal as an integrated pest management tool for a wider audience of beekeepers.
Auslöser und Ausprägung des Varroa Sensitiven Hygiene (VSH) Verhaltens im Zusammenhang mit der Reproduktion der Varroamilbe Varroa destructor
(2024) Fölsch, Lina; Hasselmann, Martin
The ectoparasite Varroa destructor causes massive economic damages to the Western honey bee (Apis mellifera) and thus threatens the health of honey bee colonies worldwide. When left untreated, varroa populations can lead to high winter colony losses (Genersch et al. 2010; Traynor et al. 2020; Le Conte et al. 2010). Beekeepers must thus routinely treat against varroa to keep their colonies healthy. A sustainable solution to overcome the varroa problem is selection for varroa resistant honey bees. In addition to studies on natural selection against varroa, there is much interest in breeding varroa resistant honey bees. During varroa resistant selection the focus is often on different selection criteria, such as mite non-reproduction (MNR) and varroa sensitive hygiene (VSH). The selection criteria MNR describes the proportion of non-reproductive mites in a colony (Virag et al. 2022). VSH encompasses the specialized removal behavior of mite infested brood by worker bees (Dietemann et al. 2013; Harbo und Harris 2005). This brood removal interrupts varroa reproduction, which leads to reduced varroa infestation in honey bee colonies. The experiments in thesis were conducted as part of the SETBie project. The SETBie (Selection and Establishment of Varroa-tolerant Bee Colonies) project was a four-year selection project whose objectives included breeding a varroa-resistant honey bee in Baden-Württemberg, Germany. Several institutions and beekeeper organizations cooperated in this project. This dissertation focuses on the factors that trigger VSH behaviour, in addition to documenting the reproductive success of the mite (MNR) in selected colonies. Initial experiments investigated the relationship between VSH and the reproductive success of female Varroa (MNR). A widely held hypothesis was that the reproduction of the mite and the associated nymphal stages in the brood cells triggered the removal behaviour of the workers. However, this hypothesis was disproved by placing mites in capped brood cells and comparing the removal behaviour of reproducing mites with that of mites whose reproduction had been blocked by a special procedure (publication 1). Both groups of mites were removed at a rate of about 40% and did not differ significantly from each other. Therefore, reproduction of the mite could be excluded as a trigger for removal behavior of the workers. This result was supported by simultaneous analysis of VSH behaviour and the proportion of non-reproductive mites (MNR) in a large number of pre-selected colonies. It was also assumed that the increased number of non-reproductive mites (MNR) within a colony is directly connected to VSH behaviour, because the workers would primarily remove the reproductive mites, leaving only non-reproductive mites behind. In addition to providing evidence that mite reproduction is not the trigger of removal behaviour, our analysis of the data collected during the SETBie project showed no correlation between MNR and VSH values (publication 3). The MNR value of a colony therefore does not allow any conclusions to be drawn about the VSH value, which should be taken into account in recommendations for breeding practices. Furthermore, an experiment was conducted to rule out the possibility that removal behaviour effects the normal reproduction of the mite in the next cycle (publication 3). The need for other triggering factors for removal behaviour to occur was clearly demonstrated in this first set of experiments. Varroa mites manipulated to remove specific factors and inanimate objects were placed in capped brood cells to determine what influences removal behaviour. We found that an object (bead) alone does not induce removal behaviour (publication 2). Dead and odour-reduced mites were removed more frequently than the bead and control, but not anywhere near as frequently as live mites. We can thus assume that, in addition to the odour of the mite, the movement of the mite in particular has a signalling effect that triggers this removal behaviour. Other as yet unknown factors such as the reaction of the larvae to the parasitism are likely to play an important role in the removal behaviour of workers. The SETBie project took place over a period of four years, which allowed us to analyse colonies over several generations. Although MNR and VSH are in principle selectable traits, our analysis has shown that they are difficult to improve over multiple generations (publication 4). Colonies with low MNR values could often be improved by crossing them with a drone (artificial insemination) from a colony with a high MNR value. However, it also became clear that it is difficult to maintain high MNR values. Methodological difficulties in targeted selection of MNR/VSH also became noticeable during the collaborative project, which involved the cooperation of numerous breeders. Despite prior infestation of the selected colonies with 180 mites, it was often not possible to collect enough mites to make a valid statement about the reproductive capability of the mite. Even after opening many cells, the minimum number of 10 single infested cells could not be found, which means that MNR values could not be determined for about 63 % of the evaluated colonies due to the presence of too few mites. The selection and breeding work involved in this project is extremely labour-intensive and therefore expensive and requires a high level of expertise among the breeders. It was shown that MNR and VSH are in principle selectable and thus theoretically a Varroa-resistant honey bee line can be bred. However, for future projects, methodological problems need to be resolved or the evaluation methods of the MNR and VSH traits need to be simplified. An optimal solution would be the identification of molecular markers to support selection via genetic heritability. However, this requires further fundamental knowledge about the Varroa mite, the mechanisms that trigger the behaviour of the currently used selection traits, and more precise phenotypic definition of the resistant behaviours.
Bericht der Landesanstalt für Bienenkunde der Universität Hohenheim für das Jahr 2023
(2024) Traynor, Kirsten
Bericht der Landesanstalt für Bienenkunde der Universität Hohenheim für das Jahr 2022
(2023) Traynor, Kirsten
Bericht der Landesanstalt für Bienenkunde der Universität Hohenheim für das Jahr 2021
(2022) Rosenkranz, Peter
Zierpflanzen als Nahrungsquelle und Bewertung der Blütenmerkmale für die Attraktivität der Bestäuberinsekten im urbanen Raum
(2022) Marquardt, Melanie; Rosenkranz, Peter
Currently, an increasing extension of urban areas can be observed worldwide, which implies a concurrent loss in natural habitats. If the current biodiversity shall be preserved, efforts must be reinforced in order to provide alternative habitats for the flora and fauna in urban areas. Regarding the assessment of the ecological value of the habitat ‘city’, scientific studies came to varying conclusions. However, all of them emphasize the importance of green urban areas in promoting the urban biodiversity. It has been frequently pointed out that sufficient and suitable foraging resources are an important and basic requirement for the survival of flower-visiting insects. However, it has hardly been investigated whether ornamental plants are suitable foraging resources for insect pollinators. While this is still highly contentious, there is growing evidence that ornamental plants could contribute to the provision of pollen and nectar. But apparently, the attractivity of different ornamental plants varies widely and furthermore, not all pollinator groups can profit equally from the mostly exotic ornamental plants. At present, scientific data for all ornamental genera or even species are not available. So, the first aim of this study was the comparison of the attractivity of certain ornamental plants, in particular those with a high market value. In order to conduct such trials, already existing acquisition methods have been assessed and refined. A further and so far rarely considered focus of this thesis is the analysis of impact factors that might affect the composition and abundance of urban pollinators. In order to identify the pollinator friendliness of ornamental plants, field tests in urban areas and semi-field tests in flight tents were conducted during the years 2017 – 2019. In the first trail, raised flower beds with an identical set of ornamental plants were installed at 13 different locations in the city area of Stuttgart. During the summer months of the years 2017 and 2018, all flower beds were visited in weekly intervals. Over a time period of 20 minutes, the number of foraging insects – divided into different groups of insect pollinators – was recorded. In total, 10,565 nectar and/or pollen foraging insects were counted. First of all, this confirms that our selection of ornamental plants was used as a foraging resource by pollinating insects. The attractivity of the tested ornamental plants, however, varied to a considerable degree among the plant species and the number of counts ranged from 1.2 flower visits in 20 minutes on Bracteantha bracteata (strawflower) to 5.3 flower visits on Bidens (beggar-ticks). It is noteworthy, that the attractivity also varied within the cultivars of the same species, partly even to a greater extent than between species. Interestingly, not only the abundance but also the composition of pollinators varied among the different test plants. Furthermore, the applied statistical models indicate significant impacts of the study year and the location on the results. This highlights the need of a continuously testing of all ornamental plants in regard to insect friendliness, for which the described methods were found to be very appropriate (publication I). Pollinating insects often use characteristic floral traits of the plants for their decision to visit the respective flower. These floral traits are often genera-, species- or even cultivar-specific and have been well studied in the native plants. In contrast, very little is known about the role of floral traits in ornamental plants. This includes e. g. the petal colour, several floral morphomet-rics or the floral scent of different plants. The impact of these traits on attractivity for insects was analysed in semi-field experiments using Calibrachoa cultivars and Bombus terrestris as model pollinator. Similar to the first part of the thesis, the attractivity of the different cultivars varied significantly. While the floral scent explained the observed differences in attractivity only to a small extend, it could be shown unequivocally that the petal colour constitutes a significant factor in the attractivity on B. terrestris. For a better understanding on the impact of certain floral traits for pollinating insects, however, there is further research required (publication II).
Charakterisierung der Qualität von Blütenpollen in unterschiedlichen Regionen Baden-Württembergs
(2022) Friedle, Carolin Gertrud Maria; Hasselmann, Martin
Honey bees (Apis mellifera) collect nectar and pollen from plants to feed their brood. Pollen provides a wide range of nutrients, such as proteins and lipids, but also carbohydrates, vitamins and enzymes. Because of these ingredients, pollen is also attractive to humans and is used as a dietary supplement. However, honey bees collect pollen not only from wild plants, but also from flowering crops grown in agriculture. Accordingly, contamination from plant protection products can be found in bee pollen and bee bread. In order to get a deeper insight into the occurrence and distribution of pesticide residues during an entire season, a total of 102 daily pollen samples were collected from April to July 2018 using pollen traps in an orchard in southern Germany. Almost 90% of the pollen samples showed detectable levels of pesticide residues. A total of 29 pesticides were detected in the samples, with more than half being fungicides, followed by insecticides and herbicides. Maximum concentrations of up to 4500 ng/g could be measured at the end of April. Samples collected in early May and late June also showed high levels of pesticides. A general risk management was performed to assess the risk of the detected pesticide concentrations for honey bees. The microbial quality of bee pollen is highly dependent on its botanical and geographic origin, as well as climatic conditions and post-harvest processing steps by the beekeeper. If no processing steps such as freezing or drying follow after harvest, the growth of microorganisms can be promoted and the pollen quality can be influenced by negative side effects such as fermentation or the production of mycotoxins. Bacterial and fungal colonies can be determined both by culture-dependent methods such as colony counting on plates and by culture-independent methods such as 16-rRNA amplicon sequencing. Following the hypothesis that storage conditions influence the composition of microorganisms in bee pollen, freshly harvested bee pollen was stored for seven days in June 2018 and 2019 under defined conditions (cold, room temperature, warm) and analyzed by sequencing 16S and 18S PCR amplicons. The bacterial community varied slightly between the sites studied and showed no significant difference between the storage conditions. The fungal community showed significant differences both between the studied sites and between the different storage conditions. The dominant fungal genera in the pollen samples were Cladosporium, Aspergillus and Zygosaccharomyces. While Cladosporium was most dominant in freshly collected pollen and the percentage decreased during storage, Aspergillus and Zygosaccharomyces showed a significant increase especially under warm storage conditions. Other contaminants naturally produced by plants can also have negative impacts on human health. Pyrrolizidine alkaloids belong to a group of phytochemicals, of which more than 600 structures are known in around 3% of all flowering plants worldwide. PA are known to be able to cause both acute poisoning and chronic damage or cancer in animals and humans. In July 2019, pollen was collected at 57 locations in Baden-Württemberg and analyzed for 42 different PAs and their N-oxides in order to expand knowledge about PA contamination in pollen and to be able to estimate the risk of the concentrations. A total of 22 different PAs were detected in over 90% of all samples examined. Only 5% of the PA were obtained as PA from plants of Senecio sp. identified, while 95% of PAs with a botanical background are from Echium sp. and Eupatorium sp. could be identified. The maximum total concentration of PA per sample was determined to be 48,400 ng/g. According to the risk values calculated by the BfR, however, 42% of the samples represented an increased risk to human health.
Bericht der Landesanstalt für Bienenkunde der Universität Hohenheim für das Jahr 2020
(2021) Rosenkranz, Peter
Bericht der Landesanstalt für Bienenkunde der Universität Hohenheim für das Jahr 2019
(2020) Rosenkranz, Peter
The production of melezitose in honeydew and its impact on honey bees (Apis mellifera L.)
(2021) Seeburger, Victoria; Hasselmann, Martin
Honeydew honey is a honey type which is of high economic importance in Europe. Phloem sap feeding insects of the order Hemiptera (true bugs) excrete honeydew, the key component of honeydew honey. Beekeepers move their hives between forest regions so that their bees can process the honeydew into honey. In case of high osmolality in the phloem sap of the hemipterans’ host trees, they counteract osmotic pressure by osmoregulation and produce oligosaccharides such as melezitose. Melezitose-rich honeydew honey is a major issue for beekeepers; it crystallises and obstructs the combs, leading to an economical loss. Nevertheless, precise analyses of the conditions of the occurrence of melezitose have not been realised. Furthermore, it is not known which impacts the trisaccharide has on honey bee health and the honeydew flow disease documented in beekeepers’ journals can have one explanation in the nutrition on melezitose. In order to determine influence factors for the emergence of melezitose, more than 600 honeydew droplets from defined honeydew producer species were collected under different environmental conditions (hemipteran species (host tree specific), natural area, air temperature, relative humidity, altitude, time of the year and of the day) between 2016 and 2019. The sugar spectra were analysed by high performance anion exchange chromatography with pulsed amperometric detection. To obtain the impact of melezitose on honey bee health, additional feeding experiments with daily evaluation of food uptake, gut-body weight ratio and mortality have been realised between 2017 and 2019. Additionally, comprehensive 16S rRNA Illumina sequencing of the gut microbial community has been performed. Remarkable differences could be found in the amount of melezitose between honeydew samples collected from different honeydew producer species and according to different environmental conditions. Air temperature increases and decreases in relative humidity increased the melezitose production in honeydew by the observed seven hemipteran species. Both, scale insect species on Picea abies and aphid species on Abies alba produced significantly less honeydew containing melezitose than aphid species on Picea abies. Additionally, honeydew with increased melezitose content was significantly more frequent collected in natural areas with limited water reservoir capacities, at higher altitudes and years with low precipitation. All results lead to the conclusion that hemipteran species produce more melezitose when the host trees have less access to water, increasing the osmolality of the phloem sap and indirectly enhancing the osmoregulation with producing melezitose by hemipteran species. Bees fed with melezitose showed increased food uptake and higher gut-body weight ratio than the control groups. Furthermore, melezitose feeding caused disease symptoms such as swollen abdomen, abdomen tipping and impaired movement and a significantly higher mortality than in control groups. Gut microbiota analyses indicated a shift of the bacterial species Lactobacillus Firm-4 and Lactobacillus kunkeei in favour of Lactobacillus Firm-5 in melezitose fed bees. This PhD project provides the important knowledge about the indicators that point out an enhanced melezitose production. This is a valuable contribution to design a warning system for beekeepers that will help to prevent harmful nutrition for honey bees or crystallised honey in the future by timely removal of bee colonies from local regions at risk. Additionally, feeding experiments point out the high effort that is required for the degradation process of the large-molecule melezitose. This effort might lead to a higher uptake of food, heavier guts, shorter lifespan and a higher susceptibility to intestinal diseases. Finally, an evidence was presented that the lactic acid bacteria of the gut microbiota are significantly involved in the digestion of melezitose.
Bericht der Landesanstalt für Bienenkunde der Universität Hohenheim für das Jahr 2018
(2019) Landesanstalt für Bienenkunde; Rosenkranz, Peter
Bericht der Landesanstalt für Bienenkunde der Universität Hohenheim für das Jahr 2017
(2018) Landesanstalt für Bienenkunde; Rosenkranz, Peter
Bericht der Landesanstalt für Bienenkunde der Universität Hohenheim für das Jahr 2016
(2017) Landesanstalt für Bienenkunde; Rosenkranz, Peter
Bericht der Landesanstalt für Bienenkunde der Universität Hohenheim für das Jahr 2015
(2016) Landesanstalt für Bienenkunde; Rosenkranz, Peter
Bericht der Landesanstalt für Bienenkunde der Universität Hohenheim für das Jahr 2014
(2015) Landesanstalt für Bienenkunde; Rosenkranz, Peter
Bericht der Landesanstalt für Bienenkunde der Universität Hohenheim für das Jahr 2013
(2014) Landesanstalt für Bienenkunde; Rosenkranz, Peter
Der Einfluss von Wirtsfaktoren der Honigbiene (Apis mellifera L.) auf den Reproduktionserfolg der parasitischen Milbe Varroa destructor (Anderson & Trueman) auf die Auswirkungen einer horizontalen Verbreitung des Parasiten auf den Befall der Bienenvölker
(2014) Frey, Eva; Bessei, Werner
The honey bee colony is faced with a huge number of pathogens, including bee viruses, bacteria, fungi and mites. Among these pathogens, the ectoparasitic mite Varroa destructor is considered the most important parasite of the honey bee worldwide. This mite was discovered at the beginning of the last century in South East Asia within colonies of the original host, the Eastern honey bee Apis cerana. From the middle of the last century the mite has been spread worldwide by transports of infested A. mellifera colonies with dramatic consequences for both, feral and managed honey bee colonies. In the meantime this parasite has become the most serious economic problem for global beekeeping. In temperate climates nearly all honey bee colonies are infested and without yearly Varroa treatments these colonies would collapse within a few years. This confirms that a stable host parasite relationship has not been established yet. Therefore the control of V. destructor still represents the main challenge for beekeeping. The main reason for host damages is the dramatic increase of the Varroa population during the season. Our honey bee colonies are obviously unable to control this population dynamic of the parasite. The increase of the mite population is influenced by the reproductive rate of Varroa females within individual brood cells, by host-parasite-interactions on the colony level and by interactions among honey bee colonies on the population level. The dissertation at hand presents experimental approaches and results at all three levels. On the individual level we were able to demonstrate that age-dependent signals of the honey bee larvae not only activate the oogenesis of the Varroa females but even trigger the further course of mite reproduction. Our studies on the activation of the Varroa reproduction revealed that exclusively larvae within 18 h (worker) and 36 h (drones), respectively, after cell capping were able to stimulate the mite’s oogenesis. Furthermore, we were able to confirm for the first time the presence of a signal in the host larvae allowing the reproducing mites to adjust their own reproductive cycle to the ontogenetic development of the host. Under certain conditions such host signals can even stop an oogenesis of the female mite that has already been started. From an adaptive point of view that sort of a stop signal enables the female mite to save resources for a next reproductive cycle if the own egg development is not sufficiently synchronized with the development of the host. My results indicate that age specific volatiles of the larval cuticle are involved in the regulation of mite reproduction. According to preliminary quantitative GC–MS analysis we suggest certain fatty acid ethyl esters as candidate compounds. These host signals – either involved in the activation or in the interruption of the Varroa reproduction – offer possibilities to influence the reproductive success of Varroa females and might therefore be used for biological control in the future. Within an EU cooperation project we could additionally demonstrate that the so called temporary infertility of Varroa females is significantly correlated with three QTL of the host larvae. This confirms a genetic basis for host resistance factors that inhibit the mite reproduction. For this study we made use of the fact that we had access to a honey bee population at the island of Gotland, Sweden that has survived mite infestation without any treatment for more than 10 years. We crossed a queen from this tolerant population with drones from susceptible colonies to rear hybrid queens and produced a mapping population of haploid drones from these hybrids. Because honey bees have a haplodiploid sex determination, the haploid drones provide an extremely simple and highly efficient model system for genetic studies. Subsequently, we mapped three candidate target regions on chromosomes 4, 7, and 9. Although the individual effect of these three QTL was found to be relatively small, the set of all three had significant impact on the suppression of V. destructor reproduction by epistasis. The detection of this epistatic interaction was only possible because we used the simple genetic make-up of haploid drones. For studies on Varroa resistance on the colony level and for selection programs the interactions among the colonies of the local honey bee population have to be considered. In two experimental approaches I was able to prove that the invasion of Varroa mites from neighboring colonies – often called “reinvasion” – significantly influences the population dynamic of the parasite within the colony. First, we quantified the number of mites invading individual colonies in relation to the invasion pressure (= number and distance of infested colonies). For this approach we made use of an isolated military training area near Münsingen at the Swabian Alb not accessible to other beekeepers. We established ten “mite receiver colonies” continuously treated against V. destructor and placed them at distances of 1m to 1.5 km from four heavily infested “mite donor colonies”. In the donor colonies, we estimated the population of bees, brood, and V. destructor at three week intervals. The invasion of mites into the receiver colonies was recorded every 7-12 days. During the measurement period of about two months, between 85 and 444 mites per colony were introduced into the receiver colonies. Surprisingly, there were no significant differences in the invasion rates in relation to the distance between donor and receiver colonies. The second approach was performed under more realistic field conditions of two experimental apiaries established in regions with high and low bee densities, respectively. Additionally, in this experiment we analyzed the multiplication of the invaded mites. Thereby we confirmed that horizontal transmission plus the reproduction of the invaded Varroa mites can cause an exponential increase of the mite population that may exceed the damage threshold within three months. We were further able to show that the invasion rates – and therefore the final infestation – differ significantly according to the number of honey bee colonies in the neighborhood of the apiary: At the site with a high bee density, the average invasion rate per colony over the entire three and a half months period was 462 mites per colony compared to only 126 mites per colony at the site with a low bee density. As a consequence, the colonies of the apiary at the high bee density site revealed an average final infestation in November of 2,082 mites per colony compared to 340 mites per colony at the low bee density site. The highly infested colonies lost about three times more bees compared to the lower infested colonies – obviously a result of Virus infections transmitted by Varroa mites. With my different approaches I was able to add further elements of knowledge for a better understanding of how host factors and ambient conditions influence the Varroa reproduction within individual brood cells and the population dynamic within a honey bee colony. A better knowledge of these host parasite interactions is essential for the selection of mite resistant colonies and further more important for the development of concepts for an effective Varroa treatment.
Bericht der Landesanstalt für Bienenkunde der Universität Hohenheim für das Jahr 2012
(2013) Landesanstalt für Bienenkunde; Rosenkranz, Peter