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cobi12308-sup-0001-SupMat.pdf153KFurther details on the data sets used (Appendix S1), details on calculating the expected correlation (Appendix S2), a figure comparing the predicted and observed correlations between the indices and the data (Appendix S3), and a figure showing the avian Living Planet Index (Appendix S4) are available on-line. The authors are solely responsible for the content and functionality of these materials. Queries (other than absence of the material) should be directed to the corresponding author.

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