American bumblebee
Bombus pensylvanicus
The American bumblebee is a large, long-tongued bumblebee that nests at or near ground level in tall grass, with annual colonies that fly roughly May through September and forage as broad generalists across grasslands, fields, and open habitats. Queens, workers, and males gather nectar and pollen from many plant families, with documented use favoring sunflowers, clovers, goldenrods, and boneset. Once the most commonly recorded bumblebee in the United States, it has declined roughly 89 percent in relative abundance, so a diverse, season-long succession of native bloom directly supports a species now in serious decline.
Conservation
In steep, well-documented decline (roughly an 89 percent drop in relative abundance and major range contraction, especially in the north). Assessed Vulnerable on the IUCN Red List (2015, Hatfield et al.). The U.S. Fish and Wildlife Service issued a positive 90-day finding in September 2021 on a petition to list it under the Endangered Species Act; it is petitioned but not yet federally listed.