Pollinators of Spring

By Linda Relson, with Pam Phillips

Spring is a really exciting time to see the landscape coming back to life.  On multiple occasions in the last couple of weeks, I've seen queen bumblebees, Bombus spp., drinking nectar from cherry blossoms, and zooming along the ground looking for nesting sites.  It’s a sure sign of the season and it lifts my spirits every time. 

I even saw my first mourning cloak butterfly, Nymphalis antiopa, recently while walking in a conservation land in Lexington.  These are some of the first butterflies we see in the Spring because they hibernate through winter as adult butterflies in hollow trees and woodpiles (reference and image source).  Other types of butterflies and moths overwinter as eggs, caterpillars or pupae, so we don’t see the adults in flight until later months.

In my own yard, I am thrilled to see my perennial mining bee colony emerge in a flurry of activity.  These bees are Dunning's miners, Andrena dunningi, and they live in a section of my garden that is quite bare in early spring, before the plants have leafed out.  The area gets sun in the afternoon, and the bees tend to be most active when the ground is warmed by the sunshine and the wind is low.

These bees emerged from tunnels in the ground, having developed from eggs that were laid last Spring.  Females dig tunnels in the soil, laying eggs and provisioning each egg with pollen (protein-rich food source) along the way.  The tunnels are about the width of a pencil, around 6-8mm.

These bees are about the size of a honeybee, with shiny black abdomens, (or butts). The females are slightly larger, with darker orange on their thorax (midsection).  They also have fuzzy legs which hold pollen like tiny brushes. The males are smaller, with a lighter yellow color fuzz on their thorax.  Males do not collect pollen from flowers, so their legs are and much skinnier.

Unlike honeybees and other social bees that live in hives, mining bees do not typically act defensive towards humans near their nests.  This makes for great up-close bee-watching, without fear of being stung.