Bill Glass, photo above, is the author of this post:
When I worked as the ecologist at Midewin National Tallgrass Prairie, every couple of years we’d get a request from a beekeeper to put out honey bee hives at Midewin. The beekeeper was looking for a safe, productive place for the hives. A place where there was a good source of nectar and pollen and free of pesticides. A natural area seems the ideal place, at least to the beekeeper. We always struggled with these requests. We just didn’t have enough information to make an enlightened decision. Fortunately the Prairie Plan we were working under stated that no non-native animals should be introduced and we followed this plan to keep honey bees out. We just felt we should be promoting native bees and the honey bees could be competition.
Recently, the Xerces Society sponsored a workshop on Best Management Practices for Pollinators at the 2019 Natural Areas Conference in Bloomington, Indiana. Most of the talks centered on bees because they are such good pollinators and they actively move pollen around the landscape. Pollination by most other pollinators is accidental although many flowers have adaptations to improve the chances of pollination. The presentations covered the relationships between native bees and honey bees. Had I heard these talks previously I could have used this research to support our decision for not allowing honey bees in restored prairies. Here are some facts I learned. Four potential risks were presented.
- Competition with native bees. Studies have shown that honey bees do complete with native bees and can displace native bees. A study by Goulson (2003) showed that a single honey bee hive consumes 20-130 lbs./year of pollen, pollen that is no longer available to native bees. Some studies have shown neutral effects. Unfortunately most of the studies don’t show a causal relationship for the decline of native bees in competition with honey bees. Even without a mechanism for the decline, it appears there is competition between native bees and honey bees.
- Disease transmission to native bees. As with competition, transmission of disease is something for natural areas managers to worry about. Although a few studies have shown a clear mechanism or causal relationship for disease transmission, most studies haven’t.
- Risks to native plant communities. Studies have suggested that some plants benefit from honey bees doing most of the pollination while other plants may be harmed. Additionally honey bees may preferentially pollinate non-native invasive plant species helping these pests spread into natural areas.
- Risk to other wildlife. This pertains to black bears getting habituated to raiding honey bee hives and increasing bear-human interactions. This is not something I had to worry about.
So to answer the question are native bees and honey bees compatible – in my mind they probably aren’t compatible in natural areas. With that said there is nothing wrong with honey bees for crop production and there may be local reasons to allow hives into natural areas. Site managers just need to make informed decisions whether honey bee hives in a natural areas fits their management goals. For more information the Xerces Society has a publication An Overview of the Potential Impacts of Honey Bees to Native Bees, Plant Communities, and Ecosystems in Wild Landscapes: Recommendations for Land Managers.
The Xerces Society publishes management recommendations to protect pollinators for land managers and other pollinator-related resources. Most of these publications are in PDF formate and can be downloaded at the Xerces Society website, under resources.
One of the things that I’ve wondered about is first year of a restoration project. If we’re converting an agricultural field to a native prairie, there may not be sufficient native bees around in the first place. If we really want our planted natives to take off, produce seed and expand, having honey bees around to promote pollination and seed set might be a positive thing. It would be a nice little study to see what the seed set rates were on annual wildflowers in a relatively pollinator poor restoration zone vs one with honey bee boxes.
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