Two very similar species of Bumblebees occur in this area; Yellow-faced and Obscure; the latter mimics the former. I have tentatively assigned this one to Yellow-faced (B. vosnesenskii). It may be distinguished from the Obscure Bumblebee (B. caliginosus) by its shorter back hairs and lack of yellow hairs on the underside of its abdomen. B. vosnesenskii. is also much more common than B. caliginosus in this area. See McFrederick.
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