Because we focus the majority of our time and energy into honey bees by working in the field, running samples and writing reports, it is easy for us to forget that other pollinators exist and play an important part in our ecosystem. One such example of another valuable pollinator is the sweat bee, or Halictidae, from the order of Hymentoptera. Per Bug Guide there are over 4,300 species and ~80 genera worldwide https://bugguide.net
These tiny bees range from the less than 1/4 inch to 3/4 inch in length and can have bright, dark or metallic coloring. You may recognize the most commonly seen sweat bee with a green, metallic exoskeleton in the photo below. Sweat bees occupy a number of different habitats such as city sidewalk cracks or soil, but lucky for us, are non-aggressive. They most often nest in the ground though a few varieties make their homes in rotting wood. While some sweat bees are solitary others are more social, building nests together. For example, those that nest in the ground begin to do so in April, digging burrows in soil and then placing pollen and nectar at the end of the tunnels in preparation for larvae. Some of the overwintered females in the nest will take on the worker function while others will lay eggs and eventually, only one egg laying female remains. At this point some of the females will mate; lay eggs that overwinter as larvae or pupae, living through the winter to begin the process again the next spring.
Sweat bees benefit plants as they feed on nectar and pollen, pollinating in the process. You may be wondering where they get the name ‘sweat bee.’ While they do feed on pollen and nectar, the bee is also attracted to human perspiration. Yum. A light brush will dislodge them and they will most likely not bother you again, however if you do happen to get stung it is not a painful as that of a honey bee. Male sweat bees, common with Apis species, also do not sting. So although the bees can be annoying in the heat of the summer, they are really nothing to worry about, rather they are just another important pollinator that helps to keep our ecosystem running smoothly.