Native Bee Spotlight: Yellow Faced Bees ~ Hylaeus spp.

Yellow Faced Bees ~ Hylaeus spp.

Yellow Faced Bees are tiny black bees with yellow (sometimes white) markings on their face, thorax and legs. Often mistaken for tiny solitary wasps, these bees have quite shiny bodies due to the lack of hairs.

Occurring from late May through to September, we will see Yellow Faced Bees in early spring, then again in late summer with a gap in between.
Some of the first native plants to look for Yellow Faced Bees in spring are Golden Alexanders (Zizia spp.). This female is feeding on pollen of Golden Alexander. Yellow Faced Bees are different from other native bees because they collect pollen and nectar in their crop. They have no pollen-collecting combs on their legs or abdomens.

Pollen is brushed with their forelegs from their head and thorax and then collected in the mouth.

Females collect pollen and nectar, and regurgitate the liquid mixture to provision the brood cells. An egg is laid on top of the mixture where the larva will hatch and consume the liquid.

Yellow Faced Bees nest in cavities, tunnels in pithy wood, or even holes in wood. Their brood cells are separated with a cellophane like material.

A Yellow Faced Bee visiting Canada Anemone (Anemone canadensis) for pollen in early spring.
In late summer look for Yellow Faced Bees nectaring on Swamp Milkweed (Asclepias incarnata). I had several dozen visiting just one plant this summer.

Although Yellow Faced Bees are short-tongued, their small size allows them access to the nectar of many flowers.
They also visit Common Boneset (Eupatorium perfoliatum) in late summer.

Source: Attracting Native Pollinators: The Xerces Society Guide, Protecting North America's Bees and Butterflies