Western Bumble Bee vs Dotted Bee Fly

Side-by-side species comparison

Attribute Western Bumble Bee Dotted Bee Fly
Scientific Name Bombus occidentalis Bombylius discolor
Order Hymenoptera Diptera
Family Apidae Bombyliidae
Size 10-22 mm 10-14 mm
Habitat Mountains Beaches & Coastal
Diet Nectar Feeders Nectar Feeders
Regions Western North America Europe
Conservation Vulnerable Least Concern

Western Bumble Bee

A once-common bumble bee of western North America that has experienced dramatic population declines since the late 1990s. They nest underground in abandoned rodent burrows.

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Did You Know?

Their catastrophic decline is linked to a pathogen accidentally spread through commercial bumble bee rearing facilities.

Dotted Bee Fly

A spring-flying bee fly distinguished from its commoner relative by spotted wings and a darker fur coat. Its larvae parasitize mining bee larvae of the genus Andrena.

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Did You Know?

It appears only in spring for a few weeks, closely tracking the flight season of its specific Andrena bee hosts.