Getting to Know the Sweat Bees of North Carolina

Sweat bees are a common type of bee found throughout North Carolina As their name suggests, they are attracted to perspiration and are often spotted landing on people to lick up the salt from their sweat While the name “sweat bee” may conjure up images of a bothersome pest, these bees are generally not aggressive and many species are important pollinators. Let’s take a closer look at these fascinating insects and how to identify some of the most common sweat bee species in North Carolina.

What Are Sweat Bees?

Sweat bees belong to the bee family Halictidae. There are over 1000 species of sweat bees in North America alone. Most species are small to medium-sized ranging from 0.12 to 0.5 inches in length. They can be identified by their metallic coloring which is often black, green, blue, or bronze.

Sweat bees get their name from their attraction to perspiration, which they lap up to obtain sodium. They will often land on people to drink their sweat. Despite this behavior, sweat bees rarely sting. Only females have stingers, which are primarily used to defend their nests. Males cannot sting at all.

Why Are Sweat Bees Important?

While sweat bees can be mildly annoying if they land on you, they provide valuable pollination services Many plants rely on sweat bees as their main or sole pollinator. Sweat bees use their long tongues to reach nectar in flowers that other bees cannot access They carry pollen from flower to flower as they forage, allowing the plants to reproduce.

Some species of sweat bees have very specialized pollinating relationships with certain plants. For example, the southeastern blueberry bee (Habropoda laboriosa) is an important pollinator of rabbiteye blueberry crops. Without this species, there would be no commercial rabbiteye blueberry production!

Common Sweat Bee Species in North Carolina

North Carolina is home to over a dozen sweat bee species. Here are a few of the most frequently encountered:

Metallic Sweat Bee (Agapostemon spp.)

This aptly named bee has a vibrant green-blue metallic coloring on its head and thorax. The females have striped abdomens. Metallic sweat bees create nests in the ground by burrowing tunnels. They emerge in mid to late summer and are attracted to flowers in the daisy, aster, and goldenrod families.

Striped Sweat Bee (Halictus ligatus)

One of the most common sweat bees in North Carolina, striped sweat bees have a black head and thorax with white and black striped abdomens. They nest underground, often in large aggregations with hundreds of bees. Females are around 0.3 inches long. Striped sweat bees fly from spring through fall and visit many flower types.

Green Sweat Bee (Augochlorella aurata)

This small bright metallic green bee grows to around 0.2 inches long. It is covered in hair, giving it a fuzzy appearance. Green sweat bees prefer to nest in rotting wood or stems and are most active in mid to late summer. They prefer composite flowers and can be spotted feeding on goldenrod and asters.

Digger Bee (Anthophora abrupta)

One of North Carolina’s largest sweat bees, digger bees are over 0.5 inches long. They are robust bees with black and white furry stripes. As their name indicates, they nest underground. Digger bees fly early in spring and are important pollinators of fruit trees and wildflowers. The males have long curled mouthparts.

Attracting and Supporting Sweat Bees

Here are some tips to make your yard or garden sweat bee-friendly:

• Plant native wildflowers like asters, sunflowers, and milkweed which provide nectar and pollen.

• Leave some areas of bare soil for ground-nesting bees.

• Put out “bee blocks” made of pre-drilled wood for stem-nesting bees.

• Avoid pesticide use which can be harmful to bees.

• Include water sources like a small pond or fountain.

• Maintain a diversity of bloom times to support bees throughout the seasons.

• Leave fallen leaves and sticks since bees use these materials to build nests.

• Reduce lawn areas and increase flower-rich habitat.

With a little understanding and appreciation, sweat bees can be welcomed members of the backyard ecosystem rather than pests. Their small size belies the huge benefits they bring as prolific pollinators. Paying attention to sweat bees provides a fascinating window into the often overlooked world of native bees.