Species Insects & ArthropodsBlue Mud Dauber

Blue Mud Dauber

Chalybion californicum

CommonInsect & Arthropod
Illustration of Blue Mud Dauber (Chalybion californicum)

The Blue Mud Dauber is a stunning metallic blue wasp with iridescent wings that specializes in attacking and provisioning its nests with black widow spiders. It often takes over abandoned nests of other mud daubers rather than building its own. Its habit of seeking out black widow spiders makes it beneficial around human structures.

Habitat
Buildings, rock outcrops, gardens, and areas with black widow spiders
Diet
Adults: nectar. Larvae: paralyzed black widow and other spiders
How common
Common

Best time to see a Blue Mud Dauber

The best time to see a Blue Mud Dauber is May–July, when about 61% of U.S. sightings happen, based on 8,175 research-grade iNaturalist observations.

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