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A global-scale expert assessment of drivers and risks associated with pollinator decline

An Author Correction to this article was published on 27 August 2021

This article has been updated


Pollinator decline has attracted global attention and substantial efforts are underway to respond through national pollinator strategies and action plans. These policy responses require clarity on what is driving pollinator decline and what risks it generates for society in different parts of the world. Using a formal expert elicitation process, we evaluated the relative regional and global importance of eight drivers of pollinator decline and ten consequent risks to human well-being. Our results indicate that global policy responses should focus on reducing pressure from changes in land cover and configuration, land management and pesticides, as these were considered very important drivers in most regions. We quantify how the importance of drivers and risks from pollinator decline, differ among regions. For example, losing access to managed pollinators was considered a serious risk only for people in North America, whereas yield instability in pollinator-dependent crops was classed as a serious or high risk in four regions but only a moderate risk in Europe and North America. Overall, perceived risks were substantially higher in the Global South. Despite extensive research on pollinator decline, our analysis reveals considerable scientific uncertainty about what this means for human society.

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Fig. 1: The four-box model for the qualitative communication of confidence.
Fig. 2: Assessment of the importance of eight major drivers of pollinator decline, for six regions and a global median (right).
Fig. 3: Assessment of the risks to human well-being associated with pollinator decline.

Data availability

Figures 2 and 3 represent scores from round 3 of a Delphi process with n = 20 expert scorers. Medians and interquartile ranges for these scores are presented in full in Supplementary Tables 2 and 3; the raw data are shown in Extended Data Figs. 2 and 3.

Change history


  1. The Assessment Report of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services on Pollinators, Pollination and Food Production (IPBES, 2016).

  2. Potts, S. G. et al. Safeguarding pollinators and their values to human well-being. Nature 540, 220–229 (2016).

    Article  CAS  PubMed  Google Scholar 

  3. Chaplin-Kramer, R. et al. Global malnutrition overlaps with pollinator-dependent micronutrient production. Proc. R. Soc. B (2014).

  4. Powney, G. D. et al. Widespread losses of pollinating insects in Britain. Nat. Commun. 10, 1018 (2019).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  5. Koh, I. et al. Modeling the status, trends, and impacts of wild bee abundance in the United States. Proc. Natl Acad. Sci. USA 113, 140–145 (2016).

    Article  CAS  PubMed  Google Scholar 

  6. Reilly, J. R. et al. Crop production in the USA is frequently limited by a lack of pollinators. Proc. R. Soc. B 287, 20200922 (2020).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  7. Aizen, M. A. et al. Global agricultural productivity is threatened by increasing pollinator dependence without a parallel increase in crop diversification. Glob. Change Biol. 25, 3516–3527 (2019).

    Article  Google Scholar 

  8. Chaplin-Kramer, R. et al. Global modeling of nature’s contributions to people. Science 366, 255–258 (2019).

    Article  CAS  PubMed  Google Scholar 

  9. Moritz, R. F. A. & Erler, S. Lost colonies found in a data mine: global honey trade but not pests or pesticides as a major cause of regional honeybee colony declines. Agric. Ecosyst. Environ. 216, 44–50 (2016).

    Article  Google Scholar 

  10. Senapathi, D., Goddard, M. A., Kunin, W. E. & Baldock, K. C. R. Landscape impacts on pollinator communities in temperate systems: evidence and knowledge gaps. Funct. Ecol. 31, 26–37 (2017).

    Article  Google Scholar 

  11. Soroye, P., Newbold, T. & Kerr, J. Climate change contributes to widespread declines among bumble bees across continents. Science 367, 685 (2020).

    Article  CAS  PubMed  Google Scholar 

  12. Woodcock, B. A. et al. Country-specific effects of neonicotinoid pesticides on honey bees and wild bees. Science 356, 1393–1395 (2017).

    Article  CAS  PubMed  Google Scholar 

  13. Carvell, C. et al. Bumblebee family lineage survival is enhanced in high-quality landscapes. Nature 543, 547 (2017).

    Article  CAS  PubMed  Google Scholar 

  14. Tonietto Rebecca, K. & Larkin Daniel, J. Habitat restoration benefits wild bees: a meta‐analysis. J. Appl. Ecol. 55, 582–590 (2017).

    Article  Google Scholar 

  15. Wintermantel, D., Odoux, J.-F., Chadœuf, J. & Bretagnolle, V. Organic farming positively affects honeybee colonies in a flower-poor period in agricultural landscapes. J. Appl. Ecol. 56, 1960–1969 (2019).

    Google Scholar 

  16. Dicks, L. V. et al. Ten policies for pollinators. Science 354, 975–976 (2016).

    Article  CAS  PubMed  Google Scholar 

  17. FAO’s Global Action on Pollination Services for Sustainable Agriculture: National Initiatives (FAO, 2020);

  18. Conservation and Sustainable Use of Pollinators CBD/COP/DEC/14/6 30 November 2018 (Convention on Biological Diversity, 2018).

  19. Teichroew, J. L. et al. Is China’s unparalleled and understudied bee diversity at risk? Biol. Conserv. 210, 19–28 (2017).

    Article  Google Scholar 

  20. Breeze, T. D., Gallai, N., Garibaldi, L. A. & Li, X. S. Economic measures of pollination services: shortcomings and future directions. TREE 31, 927–939 (2016).

    PubMed  Google Scholar 

  21. Díaz, S. et al. Summary for Policymakers of the Global Assessment Report on Biodiversity and Ecosystem Services of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES, 2019).

  22. Hall, D. M. & Steiner, R. Insect pollinator conservation policy innovations at subnational levels: lessons for lawmakers. Environ. Sci. Policy 93, 118–128 (2019).

    Article  Google Scholar 

  23. Díaz, S. et al. Pervasive human-driven decline of life on Earth points to the need for transformative change. Science 366, eaax3100 (2019).

    Article  CAS  PubMed  Google Scholar 

  24. Mukherjee, N. et al. The Delphi technique in ecology and biological conservation: applications and guidelines. Methods Ecol. Evol. 6, 1097–1109 (2015).

    Article  Google Scholar 

  25. Kovács-Hostyánszki, A. et al. Ecological intensification to mitigate impacts of conventional intensive land use on pollinators and pollination. Ecol. Lett. 20, 673–689 (2017).

    Article  PubMed  PubMed Central  Google Scholar 

  26. Kennedy, C. M. et al. A global quantitative synthesis of local and landscape effects on wild bee pollinators in agroecosystems. Ecol. Lett. 16, 584–599 (2013).

    Article  PubMed  Google Scholar 

  27. Basu, P. et al. Scale dependent drivers of wild bee diversity in tropical heterogeneous agricultural landscapes. Ecol. Evol. 6, 6983–6992 (2016).

    Article  PubMed  PubMed Central  Google Scholar 

  28. Marques, A. et al. Increasing impacts of land use on biodiversity and carbon sequestration driven by population and economic growth. Nat. Ecol. Evol. 3, 628–637 (2019).

    Article  PubMed  PubMed Central  Google Scholar 

  29. Jayne, T. S., Snapp, S., Place, F. & Sitko, N. Sustainable agricultural intensification in an era of rural transformation in Africa. Glob. Food Security 20, 105–113 (2019).

    Article  Google Scholar 

  30. Mitchell, E. A. D. et al. A worldwide survey of neonicotinoids in honey. Science 358, 109–111 (2017).

    Article  CAS  PubMed  Google Scholar 

  31. Woodcock, B. A. et al. Impacts of neonicotinoid use on long-term population changes in wild bees in England. Nat. Commun. 7, 12459 (2016).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  32. Rundlof, M. et al. Seed coating with a neonicotinoid insecticide negatively affects wild bees. Nature 521, 77–80 (2015).

    Article  PubMed  CAS  Google Scholar 

  33. Schreinemachers, P. & Tipraqsa, P. Agricultural pesticides and land use intensification in high, middle and low income countries. Food Policy 37, 616–626 (2012).

    Article  Google Scholar 

  34. Neonicotinoid Insecticides: Use and Effects in African Agriculture: a Review and Recommendations to Policymakers (NASAC, 2019);

  35. Herrando, S. et al. Contrasting impacts of precipitation on Mediterranean birds and butterflies. Sci. Rep. 9, 5680 (2019).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  36. Brookes, G. & Barfoot, P. GM Crops: Global Socio-economic and Environmental Impacts 1996-2018 (PG Economics Ltd, 2020);

  37. Farina, W. M., Balbuena, M. S., Herbert, L. T., Gonalons, C. M. & Vazquez, D. E. Effects of the herbicide glyphosate on honey bee sensory and cognitive abilities: individual impairments with implications for the hive. Insects 10, 354 (2019).

    Article  PubMed Central  Google Scholar 

  38. Zattara, E. E. & Aizen, M. A. Worldwide occurrence records suggest a global decline in bee species richness. One Earth 4, 114–123 (2021).

    Article  Google Scholar 

  39. Regan, E. C. et al. Global trends in the status of bird and mammal pollinators. Conserv. Lett. 8, 397–403 (2015).

    Article  Google Scholar 

  40. Garibaldi, L. A. et al. Wild pollinators enhance fruit set of crops regardless of honey bee abundance. Science 339, 1608–1611 (2013).

    Article  CAS  PubMed  Google Scholar 

  41. Samnegård, U., Hambäck, P. A., Lemessa, D., Nemomissa, S. & Hylander, K. A heterogeneous landscape does not guarantee high crop pollination. Proc. Biol. Sci. 283, 20161472 (2016).

    PubMed  PubMed Central  Google Scholar 

  42. Groeneveld, J. H., Tscharntke, T., Moser, G. & Clough, Y. Experimental evidence for stronger cacao yield limitation by pollination than by plant resources. Perspect. Plant Ecol. Evol. Syst. 12, 183–191 (2010).

    Article  Google Scholar 

  43. Lautenbach, S., Seppelt, R., Liebscher, J. & Dormann, C. F. Spatial and temporal trends of global pollination benefit. PLoS ONE 7, e35954 (2012).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  44. Garibaldi, L. A., Aizen, M. A., Klein, A. M., Cunningham, S. A. & Harder, L. D. Global growth and stability of agricultural yield decrease with pollinator dependence. Proc. Natl Acad. Sci. USA 108, 5909–5914 (2011).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  45. Ritchie, H. & Roser, M. Urbanization (Our World in Data, 2018);

  46. Hipolito, J., Boscolo, D. & Viana, B. F. Landscape and crop management strategies to conserve pollination services and increase yields in tropical coffee farms. Agriculture Ecosyst. Environ. 256, 218–225 (2018).

    Article  Google Scholar 

  47. Begotti, R. A. & Peres, C. A. Rapidly escalating threats to the biodiversity and ethnocultural capital of Brazilian Indigenous Lands. Land Use Policy 96, 10 (2020).

    Article  Google Scholar 

  48. Pirk, C. W. W., Strauss, U., Yusuf, A. A., Démares, F. & Human, H. Honeybee health in Africa—a review. Apidologie 47, 276–300 (2016).

    Article  Google Scholar 

  49. Gebremedhn, H., Amssalu, B., Smet, L. D. & de Graaf, D. C. Factors restraining the population growth of Varroa destructor in Ethiopian honey bees (Apis mellifera simensis). PLoS ONE 14, e0223236 (2019).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  50. Junge, X., Lindemann-Matthies, P., Hunziker, M. & Schüpbach, B. Aesthetic preferences of non-farmers and farmers for different land-use types and proportions of ecological compensation areas in the Swiss lowlands. Biol. Conserv. 144, 1430–1440 (2011).

    Article  Google Scholar 

  51. Lee, H., Sumner, D. A. & Champetier, A. Pollination markets and the coupled futures of almonds and honey bees: simulating impacts of shifts in demands and costs. Am. J. Agric. Econ. 101, 230–249 (2019).

    Article  Google Scholar 

  52. Rucker, R. R., Thurman, W. N. & Burgett, M. Colony collapse and the consequences of bee disease: market adaptation to environmental change. J. Assoc. Environ. Resour. Econ. 6, 927–960 (2019).

    Google Scholar 

  53. Breeze, T. D. et al. Linking farmer and beekeeper preferences with ecological knowledge to improve crop pollination. People Nat. 1, 562–572 (2019).

    Article  Google Scholar 

  54. Hall, D. M. & Martins, D. J. Human dimensions of insect pollinator conservation. Curr. Opin. Insect Sci. 38, 107–114 (2020).

    Article  PubMed  Google Scholar 

  55. Zommers, Z. et al. Burning embers: towards more transparent and robust climate-change risk assessments. Nat. Rev. Earth Environ. 1, 516–529 (2020).

    Article  Google Scholar 

  56. Duijm, N. J. Recommendations on the use and design of risk matrices. Saf. Sci. 76, 21–31 (2015).

    Article  Google Scholar 

  57. Peace, C. The risk matrix: uncertain results? Policy Pract. Health Saf. 15, 131–144 (2017).

    Article  Google Scholar 

  58. Morgan, M. G. Use (and abuse) of expert elicitation in support of decision making for public policy. Proc. Natl Acad. Sci. USA 111, 7176–7184 (2014).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  59. Regan, H. M., Colyvan, M. & Burgman, M. A. A taxonomy and treatment of uncertainty for ecology and conservation biology. Ecol. Appl. 12, 618–628 (2002).

    Article  Google Scholar 

  60. FAOStat (FAO, 2017);

  61. Regional Report for Africa on Pollinators and Pollination and Food Production UNEP/CBD/COP/13/INF/36 (Convention on Biological Diversity, 2016).

  62. Sutherland, W. J., Fleishman, E., Mascia, M. B., Pretty, J. & Rudd, M. A. Methods for collaboratively identifying research priorities and emerging issues in science and policy. Methods Ecol. Evol. 2, 238–247 (2011).

    Article  Google Scholar 

  63. Wickham, H. ggplot2. R v.4.0.0 (2016).

  64. Christensen, R. H. B. ordinal. R v.4.0.3 (2018).

  65. Menard, S. Applied Logistic Regression Analysis (SAGE Publications, 2002).

  66. Hill, R. et al. Biocultural approaches to pollinator conservation. Nat. Sustain. 2, 214–222 (2019).

    Article  Google Scholar 

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We thank the following people who took part in an early scoping of this exercise during writing of the IPBES Pollination Assessment, helping to define the parameters: T. Aneni, B. Brosi, S. Cunningham, M. del Coro Arizmendi, C. Eardley, A. Espindola, M. Espirito Santo, B. Freitas, N. Gallai, K. Goka, D. Inouye, C. Jung, E. Kelbessa, P. Kwapong, X. Li, A. Lopes, D. Martins, C. Maus, G. Nates, R. Paxton, J. Pettis, J. Quezada-Euan, J. Settele, H. Szentgyorgyi, H. Taki, R. Veldtman and S. Wiantoro. We thank S. Barnsley and L. Blackmore, who supported the discussion groups as note-takers during the workshops. We are grateful to T. Balcombe and C. Vidler for planning and organizing the workshop and to J. Huang for support with the figures. We thank the University of Reading’s Building Outstanding Impact Support Programme for supporting S.G.P., T.D.B. and D.S. and the workshop attendees. We would like to warmly thank IPBES for having dedicated its first assessment report to the important issue of pollinators and for having brought an unprecedented level of awareness on their importance and loss worldwide. This paper builds on some of the concepts from the IPBES pollination assessment and was, in many ways, inspired by that assessment. The views expressed here, however, represent the individual views of the authors. L.V.D. is funded by the Natural Environment Research Council (grant nos NE/N014472/1 and 2). A.K.-H. was supported by the National Research, Development and Innovation Office (FK 123813).

Author information

Authors and Affiliations



L.V.D. conceived and designed the study. L.V.D and T.D.B. contributed equally to data collection, analysis and writing the paper. S.G.P. and H.T.N. convened the expert panel. S.G.P., D.S., T.D.B., H.T.N. and L.V.D. designed, organized and ran the workshop. L.V.D., T.D.B., H.T.N., A.J., M.A.A., P.B., D.B., L.G., L.A.G., B. Gemmill-Herren, B. G. Howlett, V.L.I.-F., S.D.J., A.K.-H., Y.J.K., H.M.G.L., T.L., C.L.S., A.J.V. and S.G.P. contributed to all rounds of scoring and discussion and commented on and edited the final manuscript. D.S. contributed to discussions and commented on and edited the final manuscript.

Corresponding author

Correspondence to Lynn V. Dicks.

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The authors declare no competing interests.

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Peer review information Nature Ecology & Evolution thanks the anonymous reviewers for their contribution to the peer review of this work. Peer reviewer reports are available.

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Extended data

Extended Data Fig. 1 Definition of global regions according to biogeographical and geopolitical conditions.

Definition of global regions according to biogeographical and geopolitical conditions.

Extended Data Fig. 2 Final breakdown of scoring of direct drivers by world regions and importance.

Final breakdown of scoring of direct drivers by world regions and importance.

Extended Data Fig. 3 Final breakdown of scoring of risks by world regions, impact and components of risk (probability, scale, severity).

Final breakdown of scoring of risks by world regions, impact and components of risk (probability, scale, severity).

Supplementary information

Supplementary Information

Supplementary Tables 1–9, ordinal regression analysis results and discussion, and references.

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Dicks, L.V., Breeze, T.D., Ngo, H.T. et al. A global-scale expert assessment of drivers and risks associated with pollinator decline. Nat Ecol Evol 5, 1453–1461 (2021).

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