Field ID Tips
The White-shouldered bumble bee, Bombus appositus, is easily identified in the field by a combination of large size, bright white shoulder, black band between the wings and the entire abdomen a golden yellow.
Lisa’s father-in-law described this species as looking like they were wearing white shoulder pads. Sports analogies for the win!
No other species is similar in appearance.
The White-shouldered bumble bee, Bombus appositus, is one of our larger and more distinctive species. It is found mainly on the eastside, both on the east side of the Cascades, across north central Washington and then down and into the Blue Mountains, in the southeastern part of the state.
There have been detections over the years both on San Juan Island and also on the north side of the Olympic mountains, including as recently as July 2020, so it appears to not be solely restricted to the east side of the state.