European Wool Carder Bees Are on the Move

Seen any European wool carder bees lately?

European wool carder bees (so named because the female collects or cards plant hairs for their nests) are on the move. 

The bees, about the size of honey bees, are mostly black and yellow. The females range in body length from 11 to 13 millimeters, while the males are 14 to 17 mm. 

The males are known for being very territorial. They body-slam other insects to protect their turf, per chance to mate with the females.

The European wool carder bees, Anthidium manicatum, are natives of Europe. Their "immigrant ancestor" was first detected in the United States (New York) in 1963, and the species then began spreading west. The bees were first recorded in California (Sunnyvale) in 2007.

The species, according to research entomologist Tom Zavortink of the Bohart Museum of Entomology at UC Davis, was  accidentally introduced into New York state.  They were not purposefully introduced to pollinate alfalfa, as some reports allege, he said.

Writing in a 2008 edition of the Pan-Pacific Entomologist, Zavortink and fellow entomologist Sandra Shanks, now of Port Townsend, Wash., pointed out that several papers “have documented its spread from neighboring areas in the northeastern United States and southern Canada” and that the species has since crossed the country. It was confirmed in Colorado in 2005, Missouri in 2006, and Maine, Michigan, Maryland and California (Sunnyvale) in 2007, the entomologists wrote. Records show it was first collected in Davis on July 26, 2007.

It was well established in the Central Valley by 2008, according to Lynn Kimsey, director of the Bohart Museum of Entomology and a UC Davis distinguished professor of entomology.

We first encountered the European wool carder bee in Vacaville, Solano County, in the spring of 2010. Its plant preferences include lamb's ear (Stachys byzantine, in the mint family Lamiaceae), a perennial grown for its fuzzy, silvery gray-green foliage. It's also been collected in the figwort/snapdragon family (Scrophulariacae) and the pea and bean family (Fabaceae), according to the Zavortink-Shanks research.

In our pollinator garden, they seem to prefer foxgloves, lamb's ear, catmint and lavender. Yes, in that order...