Written by Joshua Lyon, UGA Extension Agent, Banks County , via the Georgia Green Landscape Stewards e-newsletter.
Bee hotels are a popular educational tool that provide pollinator nesting in home gardens, schools, and public landscapes. These structures are designed to provide nesting habitat for solitary native bees like leafcutter and mason bees. While bee hotels are great tools for educating people about native bees, recent research suggests that bee hotels may not always benefit native pollinators as intended and in some cases, may even create new challenges.
Recent work done by Dr. Miriam Lyon at University of Georgia found that bee hotels in Clarke County, Georgia were almost entirely occupied by non-natives, specifically the giant resin bee Megachile sculpturalis and the mason bee Osmia taurus, which have been found along the east coast of the U.S.
The giant resin bee, Megachile sculpturalis, is a large, non-native, physically aggressive bee that readily occupies artificial nesting cavities and directly competes with native cavity-nesting bees. Because bee hotels concentrate nesting resources in one location, they may unintentionally give competitive advantages to species that are more aggressive or adaptable. Invasive species are often invasive because of their aggressive and adaptable behavior.
Disease and parasite buildup are also a potential problem in bee hotels. In natural settings, solitary bees nest in scattered, isolated cavities, which helps to limit the spread of pathogens and pests. Bee hotels, on the other hand, cluster a bunch of nests tightly together. Fungal diseases, mites, and parasitic wasps can become a problem if bee hotels aren’t cleaned and maintained annually.
We also have to keep in mind that only about 30% of our native bees are cavity nesters. The majority of native bees in Georgia and across the Southeast are ground nesters that don’t benefit from bee hotels. By focusing heavily on hotels, we risk overlooking the broader habitat needs of the full pollinator community.
Bee hotels are not necessarily bad, but we should use them mindfully. For those looking to make a meaningful impact on native bee communities, focusing on habitat diversity and ecological processes will go much further than any single structure.
To support a wider range of native bees, follow these tips!
- Leave areas of bare, well-drained soil: Ground-nesting bees need this access to the ground. Avoid excessive mulching
- Avoid excessive disturbance: minimize clean up and tillage. Avoid pesticides when possible.
- Incorporate native plants and choose a selection that blooms in each season: A diverse selection of native flowering plants ensures continuous pollinator resources.
- Retain dead wood and stems: Standing dead trees (snags), brush piles, and undisturbed plant stems offer natural nesting sites without the density issues of bee hotels.
