This report of the National Research Council’s Committee on the Status of Pollinators in North America is an assessment of pollinating animals in the United States, Canada, and Mexico. Long-term population trends for the honey bee, the most important managed pollinator, are demonstrably downward. Similar data are not available for other managed pollinators, such as alfalfa leafcutting bees and bumblebees. There is evidence of a decline in the abundance of some wild pollinators, but the strength of this evidence varies among taxa. Long-term population trends for several wild bee species (notably bumble bees) and some butterflies, bats, and hummingbirds are demonstrably downward. For most pollinator species, however, the paucity of long-term population data and the incomplete knowledge of even basic taxonomy and ecology make a definitive assessment of status exceedingly difficult.
