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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.

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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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