Native Pollinators versus Honeybees

What does the evidence actually say about "save the bees"? The answer might surprise you.

You’ve probably heard some stats on pollinators on the news, or an infographic on social media, around the importance of pollinators; that they are responsible for nearly 85% of the world’s flower plant reproduction, and 35% of global crop production. And, of course, it’s not just the bees, native or non-native, but wasps, flies, beetles, ants, butterflies, moths, and more. There are over 4000 native species of bees in the US and Canada.¹ The bee with the highest population on the continent, the honey bee, is non-native and was introduced in the early 17th century for honey as well as wax production.

That said, we don’t actually know a whole lot about the native bees here, other than that they’re experiencing population declines. In fact, 40% of pollinator species may be at risk of extinction in the next few decades.² And it’s because of this that honeybees have quickly gone from “save the honeybee” to “the honeybee isn’t the one who needs saving” to “the honeybee is actually causing many of the pollinator problems” pretty quickly.

Let’s look at an article in Scientific American, written by Allison McAfee in 2010, called The Problem with Honeybees. She states that “High densities of honey bee colonies increase competition between native pollinators for forage, putting even more pressure on the wild species that are already in decline. Honey bees are extreme generalist foragers and monopolize floral resources, thus leading to exploitative competition—that is, where one species uses up a resource, not leaving enough to go around.” Unlike most of the other stats listed in her piece, this one isn’t even cited– and it’s not an Allison McAfee problem, either. She has a whole team that reviews that work, and it’s not just Scientific American that makes this claim, but a quick Google will show you a long list of articles highlighting the same argument, that honeybees monopolize floral resources. But is it true?

Before we talk about native pollinators versus non-natives, we’ve gotta talk about their food. One of the most damaging non-native plants we have in my part of the world is Japanese Knotweed. The thing is, not only do they have massive blooms, but their blooms come pretty late in the year, and are, theoretically, at least, important when it comes to providing a late-season pollen and nectar source before the long, cold winter.

Fortunately, people much smarter than me decided to spend some time trying to figure out if you could quantify the impacts from non-natives, as a broad category. Even more fortunately, many of those people decided to do some digging and try experiments across North America, which, while it may not represent the whole globe, is significantly better than relying on just one or two experiments. 

We have talked about the concept of specialists and generalists, and how co-evolution can lead to highly specialized and atomized relationships, where species can only get pollinated by a singular native species, and in those cases the value of each individual of the other species is crucial; obviously, those relationships don’t play out in a scenario with invasive species moving in, right? Especially when they’re moving in at such large scales, while native plants have been under a scorched earth policy.

Even before dealing with the damage of displacing natives, there are some problems with these nectar sources. The nectar of some plants contains secondary compounds, usually associated with defense against herbivores. The impacts of these compounds on pollinators are often unknown. Researchers took a common landscaping plant, rhododendrons, to find out their impacts on the health of native and non-native bees due to a chemical, grayanotoxin, a secondary compound in their nectar. Survival of the solitary bee and the bumblebee species was not affected by grayanotoxin, but honeybees were  20x more likely to die when fed solutions containing that same substance. Furthermore, solitary bees were deterred from feeding and exhibited malaise behaviors indicative of sublethal toxicity in response to consumption of grayanotoxin.³

We can start to see how these things are complicated, and that nonnatives, like rhododendrons, provide incredible amounts of nectar that, in this case, honeybees can’t even harvest nectar from, so they’re not all necessarily bad. This could be in part because there are 28 different varieties of native rhododendrons, while only one is native to just a small part of Europe, even though our decorative rhododendron is actually from Asia. Clearly, it gets complicated quickly.

Another major talking point around invasives and our non-native honeybees is the idea that because invasive plants are often from places where honeybees are also from, honeybees are really good at pollinating them and helping them produce seeds, which on the surface makes a lot of sense. And while it might be true, the basis that honeybees are causing invasives to be more successful usually ties back to one particular study, “The influence of sociality on the conservation biology of social insects” from 2001. Oddly enough, this often cited paper doesn’t actually talk about this subject in any depth, but it also cites a research project in 1994, called “An assessment of the contribution of honey bees (Apis mellifera) to weed reproduction in New Zealand protected natural areas”.⁴ This third paper that is constantly referred to as the founding source that everyone uses in their citations to say that honeybees are increasing non-native plants’ capacity to reproduce. Here’s the paper’s conclusion:

“A substantial proportion of surveyed weeds in Protected Natural Areas are probably visited by honey bees (43%) including half of the problem weeds. However, reproduction of the majority of problem weeds is characterized by plastic reproductive mechanisms and/or simple pollination mechanisms where honey bee influence is low or unimportant. Although honey bees may be important pollinators of some weeds, they probably do not contribute substantially to weed problems.”

Now, this isn’t the only source for this argument— another one that pops up repeatedly is called “Biotic Invasions: Causes, Epidemiology, Global Consequences, and Control”. Cited repeatedly— and it sounds like it should be, right? Doesn’t. Mention. Honeybees. Once. Lots of pop science writers will refer to these papers because everyone else does, but there doesn’t seem to be a whole lot of actual evidence backing up any of this.

Now, farming has some similar complications to invasives in that monocropping in particular displaces native species. The million-dollar question, from an ecological standpoint, is where the line stands where monocropping becomes a net negative between ecological destruction and scales of efficiency. We need to take a look at monocropping and how this impacts native diversity in comparison to the impacts of honeybees, which, as we’ve pointed out in a specific example above, don’t always compete with natives. That’s not always the case, but I also think that there’s an assumption that comes from the polarization of content in order to engage audiences.

In 2016, some research was done on just this; specifically, how pollinator diversity changes based on scale and how far the distance of these monocrops impacts native pollinator diversity. What they found was that row crops had a negative effect on bee abundance at as low of scales of 900 feet.⁵

While that sounds really big, that’s only like a fifth of a mile. If you drove by 5 farms on a mile stretch that were square lots, each of those leaving the very edges for native pollinators, they’d still show that negative effect despite the native pollinator space, which is nothing when we think about the scale of industrial agriculture. What also was interesting is that grass and pasture, forage crops, small grains, and open water all contributed positively to pollinator abundance, while wetlands had a negative effect. 

Now, at two miles, corn actually positively affected bee abundance and richness, while soybean acreage decreased species richness. That said, corn is wind-pollinated, but unlike soybeans, is native to North America and was grown on some scale in the region prior, and likely supports native species in other ways which allows for greater pollinator habitat. What was most interesting, though, was that unlike other studies, just any old landscape diversity—i.e. nonnative plants— within 900 feet was not found to significantly benefit pollinator diversity.  Like any research, it’s possible that the study is an anomaly, but the evidence suggests that less highly managed areas still represent degraded habitats within the landscape.

The real question should be around, well, if we can make healthy pollinator sites, how much of our farmland should be converted into native pollinator landscapes, and how does this impact both honey production and is it viable to make our monocrops native-pollinator driven?

The evidence suggests, and it’s still *really* preliminary at this point that we aren’t addressing the issue of what that might look like and how native ecologies might drive what this scale might actually be, that it can be somewhat possible. The example I want to point to is specifically from a paper written by R. David Simpson in 2018 on Almond farms, where he states that “a farmer who relied entirely on wild pollinators would set aside a little over an eighth—roughly 13%—of her land to support pollinators.”⁶

Not trying to defend modern ag by any means, but still. You’re talking about taking almost a sixth of cropland out of production here. And that doesn’t address the labor costs of managing those native wild pollinator sites either. And this brings up a more granular, but very important topic, and that’s the paradox of efficiency. The basic idea of this concept is that when things are too good at being efficient, a little bit is a great thing, but at some point, it’s diminishing returns, right?

The paradox of efficiency is often discussed in economic circles but is fully appropriate in ecological contexts as well.

The takeaway should be that a little of native habitat goes a long way. Sometimes. But like before, it didn’t seem to. Again— it’s complicated. There’s a lot of pieces to dissect, more than we have evidence to argue one way or another. We haven’t talked about, and won’t have the time or data that exists, to talk about where and how these ‘pollinator sites’ should exist. Because, again, a lot of this is still novel research, and we don’t know where it will end up. However, we do have a lot of research on the impacts of native plants and how they impact both native pollinators and non-native pollinators, and the evidence might surprise you.

The evidence, to this point, suggests that, first and foremost, native plants are more efficiently used by native pollinators, and that honeybees will draw from those natives, but even non-native plants are capable of feeding many pollinators, despite being non-native.

In Dr. Gail Langellotto's presentation at the Oregon State University Garden Ecology Lab, they discussed a research project they did comparing non-native and native plants and how they serve pollinators.

What’s interesting here is that once the non-natives were within the ecosystem for a year, they actually outperformed pollination services in comparison to natives. That said, a majority of their pollination was done by non-native honeybees.⁷, ⁸

To understand this, we have to remember that honeybees are generalists. So they can basically forage whatever, and sometimes it kills them— as we discussed earlier. So it makes sense for them to go to the least competitive plant. This is a great skill, but ultimately if everyone were to replace their, I don’t know, roses with native plants, they’d end up competing with native pollinators, and in general they’re less efficient at utilizing the pollen in those native crops, up to 55% less efficient.⁹, ¹⁰

The underlying point here is that we need more flowering plants in general. We need the ecological infrastructure that can support the insects, and that’s not just the pollinators themselves but the habitats, the reductions in pesticide use, insecticide use, and so on. And, of course, honeybees aren’t the only non-native pollinators.

We need more insect-pollinated species, and preferably a diverse, native selection. Given the current state of exotic species, we do not need to add more, and we absolutely can and should try to reduce what exists, but there’s no future where they are all removed, and honestly, I’m not even sure that would be an ideal situation. Further, much like we’ve talked about around the idea of complex systems science, not only are different pollinators specialized to certain types of plants, but some are even specialized to harvest pollen during different times of the day, helping increase resource partitioning and diversity while reducing competition.¹¹ We just need to make space for these plants and their pollinators.

That’s not to say that is all we need— we need to consider what it looks like to create better ecosystems and to understand how honeybees interact with our natives. For example, bumblebees seem to do better sharing an ecosystem with honeybees as long as the site isn’t homogenous– regardless of species' nativity.¹², ¹³ Even older bumblebees don’t get out-competed by honeybees, despite what you’d imagine.¹⁴ Further, as native pollinators have died off, non-native pollinators have stepped in to provide crucial pollination services to keep native crops from producing infertile seeds.¹⁵ But, of course, the counterweight is the monumental stack of evidence pointing to the fact that honeybees do disrupt plant-pollinator communities.¹⁶ In short, under all of the bad our honeybees do, as well as other non-native pollinators, they aren’t as bad as some might suggest. What matters is proper management and context.

And of course, there are other non-pollinator-driven honeybee problems to work out. The first, and we’ve hinted at it, is the impacts of our mono-crop food system.¹⁷ Not only is it damaging ecosystem stability, but our system of moving bees into these monocrops is getting our native bees sick.¹⁸ And there’s a bunch of reasons, and that’s part of why we’ve dedicated a whole series to honeybees. Part of it is because of how we raise them, part because of how we’ve bred them, and part because of how we manage them. Basically, they’re living despite our best efforts.

Another problem for native pollinators in particular is that we’re starting to see interbreeding between domestic bees and native bees, specifically bumblebees. This is particularly common in greenhouses, where bumblebees do a majority of the pollination because the greenhouses can’t support a honeybee hive. We’re also seeing parasites and other nasty stuff makes their way from honeybee hives to native bumblebees, whose populations are already down, as we’ve said, so adding more to this challenge isn’t exactly ideal.¹⁹

In short— there are innumerable factors that impact how honeybees interact with their environment. Some are simple fixes— integrating more insect-pollinated, native flowers can be done in an afternoon. Others are beyond the scope of what any individual can do anything about— changing how our monocrops are planted and stopping the seasonal movement of honeybees across the nation.

The Xerces Society, an organization in defense of native invertebrates, has what I think are some really good ideas around the appropriateness of honeybees. Their first question is to ask if there are any endangered pollinators in the area identified— within 4 miles is too close. For apiaries further than 4 miles from these sites, keeping 20 or less hives is the maximum recommended, and apiaries should be 4 miles apart. This also fundamentally points to the fact that beekeeping, much like any other form of horticulture or land stewardship, is almost never something that can be managed or decided individually. Our decisions expand beyond property lines and flow throughout the ecosystem regardless of our intent to make decisions based on our own best interests.

With this in mind, should you choose to continue to keep honeybees, you should understand the weight of that decision and why proper care— as we have been exploring throughout this series of articles— is so crucial in order to protect the health of our native pollinators.

If you’ve enjoyed this piece, which is equal to a 13-page chapter, of (so far) an 820-page book with 480 sources, you can support our work in a number of ways. The first is by sharing this article with folks you think would find it interesting. Second, you can listen to the audio version of this episode, #136, of the Poor Proles Almanac wherever you get your podcasts. Suppose you’d like to financially support the project, and get exclusive access to our limited paywalled content. In that case, you can become a paid subscriber on Substack or Patreon, which will both give you access to the paywalled content and in the case of Patreon, early access to the audio episodes as well.

1. https://www.usgs.gov/faqs/how-many-species-native-bees-are-united-states

2. https://naturalareas.org/docs/16-067_02_Overview-of-the-Potential-Impacts-of-Honey-Bees_web.pdf

3. Tiedeken, E. J., Egan, P. A., Stevenson, P. C., Wright, G. A., Brown, M. J., Power, E. F., Farrell, I., Matthews, S. M., & Stout, J. C. (2015). Nectar chemistry modulates the impact of an invasive plant on native pollinators. Functional Ecology, 30(6), 885–893. https://doi.org/10.1111/1365-2435.12588

4. Butz Huryn, V., & Moller, H. (1995). An assessment of the contribution of honey bees (Apis mellifera) to weed reproduction in New Zealand-protected natural areas. New Zealand Journal of Ecology, 19(2), 111–122.

5. Mogren, C. L., Rand, T. A., Fausti, S. W., & Lundgren, J. G. (2016). The effects of crop intensification on the diversity of native pollinator communities. Environmental Entomology, 45(4), 865–872. https://doi.org/10.1093/ee/nvw066

6. Simpson, R. D. (2018). Conservation incentives from an ecosystem service: How much farmland might be devoted to native pollinators? Environmental and Resource Economics, 73(2), 661–678. https://doi.org/10.1007/s10640-018-0277-1

7. Moroń, D., Skórka, P., Lenda, M., Kajzer-Bonk, J., Mielczarek, Ł., Rożej-Pabijan, E., & Wantuch, M. (2018). Linear and non-linear effects of goldenrod invasions on native pollinator and plant populations. Biological Invasions, 21(3), 947–960. https://doi.org/10.1007/s10530-018-1874-1

8. Potter, D. A., & Mach, B. M. (2022). Non-native non-apis bees are more abundant on non-native versus native flowering woody landscape plants. Insects, 13(3), 238. https://doi.org/10.3390/insects13030238

9. Debnam, S., Saez, A., Aizen, M. A., & Callaway, R. M. (2021). Exotic insect pollinators and native pollination systems. Plant Ecology, 222(9), 1075–1088. https://doi.org/10.1007/s11258-021-01162-0

10. Mogren, C. L., Rand, T. A., Fausti, S. W., & Lundgren, J. G. (2016a). The effects of crop intensification on the diversity of native pollinator communities. Environmental Entomology, 45(4), 865–872. https://doi.org/10.1093/ee/nvw066

11. Jeavons, E., van Baaren, J., & Le Lann, C. (2020). Resource partitioning among a pollinator guild: A case study of monospecific flower crops under high honeybee pressure. Acta Oecologica, 104, 103527. https://doi.org/10.1016/j.actao.2020.103527

12. Herbertsson, L., Lindström, S. A. M., Rundlöf, M., Bommarco, R., & Smith, H. G. (2016). Competition between managed honeybees and wild bumblebees depends on landscape context. Basic and Applied Ecology, 17(7), 609–616. https://doi.org/10.1016/j.baae.2016.05.001

13. Sørensen, P. B., Strandberg, B., Bruus, M., Kjær, C., Larsen, S., Hansen, R. R., Damgaard, C. F., & Strandberg, M. (2020). Modelling risk of competitive effects from honeybees on Wild Bees. Ecological Indicators, 118, 106749. https://doi.org/10.1016/j.ecolind.2020.106749

14. Iwasaki, J. M., Barratt, B. I., Jandt, J. M., Jowett, T. W., Lord, J. M., Mercer, A. R., & Dickinson, K. J. (2020). Honey bees do not displace foraging bumble bees on nectar-rich artificial flowers. Apidologie, 51(1), 137–146. https://doi.org/10.1007/s13592-019-00690-z

15. Stavert, J. R., Pattemore, D. E., Bartomeus, I., Gaskett, A. C., & Beggs, J. R. (2018). Exotic flies maintain pollination services as native pollinators decline with agricultural expansion. Journal of Applied Ecology, 55(4), 1737–1746. https://doi.org/10.1111/1365-2664.13103

16. Valido, A., Rodríguez-Rodríguez, M. C., & Jordano, P. (2019). Honeybees disrupt the structure and functionality of plant-pollinator networks. Scientific Reports, 9(1). https://doi.org/10.1038/s41598-019-41271-5

17. Broussard, M., Rao, S., Stephen, W. P., & White, L. (2011). Native bees, honeybees, and pollination in Oregon cranberries. HortScience, 46(6), 885–888. https://doi.org/10.21273/hortsci.46.6.885

18. Lanner, J., Dubos, N., Geslin, B., Leroy, B., Hernández-Castellano, C., Dubaić, J. B., Bortolotti, L., Calafat, J. D., Ćetković, A., Flaminio, S., Le Féon, V., Margalef-Marrase, J., Orr, M., Pachinger, B., Ruzzier, E., Smagghe, G., Tuerlings, T., Vereecken, N. J., & Meimberg, H. (2022). On the road: Anthropogenic factors drive the invasion risk of a wild solitary bee species. Science of The Total Environment, 827, 154246. https://doi.org/10.1016/j.scitotenv.2022.154246

19. Alger, S. A. (2020). Viruses are spilling over from managed honey bees to wild Bumble Bees. TheScienceBreaker, 06(01). https://doi.org/10.25250/thescbr.brk327