Meeting Abstract
Honey bee (Apis mellifera) and other pollinator populations are declining worldwide for unexplained reasons, threatening over $12 billion in agriculture that depends on pollination services. Fungicides are applied to prevent rot diseases while many crop plants are in bloom, leading to wide consumption by pollinators. Field colonies of honey bees were forced to feed on pollen containing Pristine®, composed of the fungicides boscalid and pyraclostrobin, at four doses ranging from 0.1 to 100x levels previously reported for agricultural pollen. Pristine® consumption produced the symptoms of colony collapse disorder, reducing colony adult populations in a dose-dependent manner with foragers dying outside the hive, and reducing over-winter survival. Pristine® consumption lowered colony populations by causing workers to forage and die earlier. Pristine® consumption reduced forager associative learning abilities, potentially reducing pollination efficiency and contributing to “lost foragers.” Pristine® increased colony pollen foraging and storage, suggesting it may act by interfering with protein digestion or absorption, perhaps by inhibiting intestinal mitochondria. Together, these findings suggest that fungicides play a significant role in pollinator decline and that the safety of fungicides for pollinators must be re-evaluated. This research was supported by USDA 2017-68004-26322.
