Genus Bombus

Bumblebee queens over-winter in small

cavities, and emerge in spring to produce one or more generations of workers that construct rambling, shallow-buried waxy nest complexes composed of dozens of interconnected globular cells. Of the 49 species known in the United States, 19 are found in the San Juan Islands. Since they are long-distance fliers undaunted

by water, bumblebees play a critical role in pollinating small isolated islands. Color patterns vary regionally, between nests, and between castes within nests.

Bumblebees like large showy flower but will also swarm on shrubs with many tiny flowers such as snowberry. Nimble and clever, they can open orchids, vetch, and other complexly folded flowers.

Bombus melanopygus

Named for its “black butt”, but also usually

conspicuously orange in the Islands, where

it is one of our most common bumblebees.

Bombus mixtus on Ladies Tresses orchid

Bombus vosnesenskii

This velvety black bee appears to prefer gardens to meadows, and is growing more abundant in the San Juan Islands.

Bombus sitkensis

A beautiful midsummer golden haired bee often seen in the islands, this one was seen at Orcas Landing nectaring on non-native Himalayan Blackberry.