The small insects known as sweat bees belong to the family Halictidae and are commonly found across most of the globe, including over 500 species in North America. These bees are often metallic, ranging in color from green to blue or bronze, and are generally smaller than a typical honeybee. Their common name comes from their attraction to human perspiration. Managing their presence involves understanding their attractants and implementing both immediate personal deterrence and long-term habitat modifications.
Understanding Sweat Bee Attraction
Sweat bees seek out humans because they need salt and moisture, which are readily available in human sweat. This attraction is particularly noticeable on hot, humid days when people are perspiring heavily and the salt concentration on the skin is higher.
Beyond human perspiration, sweat bees are drawn to other scents. They may be attracted to sweet smells from perfumes, scented lotions, and sugary drinks, mistaking them for nectar sources. The bees also seek hydration from open water sources and moist areas.
Immediate Personal Deterrence Methods
For immediate relief, strategies focus on masking the scent of sweat and creating a physical barrier. Applying a natural repellent based on essential oils can deter them from landing on the skin. Oils with strong scents like peppermint, eucalyptus, citronella, or lemongrass are effective because they overwhelm the bees’ sensitive olfactory receptors, preventing them from locating salt.
These essential oils can be applied to the skin, often diluted with a carrier, or used in outdoor diffusers. Wearing long sleeves or pants provides a physical barrier against contact. Using a fan outdoors also creates air movement that disrupts their flight path and discourages lingering.
Modifying personal grooming habits before going outside can significantly reduce attraction. Avoid using heavily scented soaps, lotions, and perfumes that mimic the smell of flowers. Wiping away sweat frequently with a towel limits the accessible salt and moisture on your skin. If you are active, moving indoors temporarily when you start to sweat heavily can be the most effective immediate solution.
Eliminating Nesting Sites and Long-Term Control
Addressing the source of the population is the most effective method for long-term control. Sweat bees are ground-nesters and prefer to build individual burrows in bare, dry, or sandy soil with little vegetation. Look for small, volcano-shaped mounds of dirt with a tiny pencil-sized hole, which indicates a nest entrance.
Habitat modification is the primary non-chemical method for deterring nesting. Covering bare patches of soil with a thick layer of mulch, wood chips, or dense groundcover plants makes the area unsuitable for burrowing. Regularly watering the lawn and garden beds also helps, as sweat bees dislike damp soil for nest construction.
If you locate individual nest holes, you can seal them up, ideally in the evening when the bees are inside the burrow. For severe, localized infestations, you may consider a targeted application of a low-toxicity insecticide, such as a liquid pyrethrin solution, directly into the nest entrance. However, because these bees are beneficial pollinators, habitat modification is generally preferred over elimination.