The extraordinary decline of pollinators mirrors the broader decline in insect biomass seen across the last few decades. Honey bees are often the face this decline, with a vocal network of beekeepers who have sounded alarms about their struggles with colony losses. Beekeeping organizations have reported incredible and unsustainable annual Honey bee colony losses of over fifty percent. Honey bees are not the only struggling pollinator. Bumble bees are facing the same threats and are likely seeing broad declines too. Unfortunately, there is little data on most species and groups of pollinator insects. There are notable exceptions; the rapid and well-documented decline of migratory Monarch butterflies at their overwintering grounds led to them being listed by the IUCN as endangered in 2022.
Cameron, S. A., and B. M. Sadd. 2020. Global Trends in Bumble Bee Health. Annu. Rev. Entomol. 65: 209–232.