Global Trends in the Status of Bird and Mammal Pollinators

Biodiversity is declining, with direct and indirect effects on ecosystem functions and services that are poorly quantified. Here, we develop the first global assessment of trends in pollinators, focusing on pollinating birds and mammals. A Red List Index for these species shows that, overall, pollinating bird and mammal species are deteriorating in status, with more species moving toward extinction than away from it. On average, 2.5 species per year have moved one Red List category toward extinction in recent decades, representing a substantial increase in the extinction risk across this set of species. This may be impacting the delivery of benefits that these species provide to people. We recommend that the index be expanded to include taxonomic groups that contribute more significantly to pollination, such as bees, wasps, and butterflies, thereby giving a more complete picture of the state of pollinating species worldwide.