Noted pollination ecologist Neal Williams, professor in the UC Davis Department of Entomology and Nematology and a 2015-2020 Chancellor's Fellow, recently discussed native bees on the international podcast, Science Friday, with host and executive producer Ira Flatow.

The podcast, "The Buzz on Native Bees in Your Neighborhood," is online.

"When I say 'bees,' you probably think of a neat stack of white hive boxes and the jars of honey on the store shelves, right?" Flatow began. "But there's a lot more to bees than that. Because around the world, there are over 20,000 known bee species, and 4,000 of them are native to the U.S. And while these native bees that live in the wild play a key role in pollinating our plants, they don't get a ton of recognition or support like the ones that live in a box." 

Professor Williams discussed a number of bee species, including bumble bees, carpenter bees, squash bees, mining bees ("bees that burrow into the ground or soil") and mason bees and leafcutter bees.

Mason bees, Williams said, build their nests "partly out of mud, which then dries. And the leafcutter bees are chewing pieces of leaves and making their nests out of those leaf pieces, either as whole chunks of leaves or as chewed up bits of leaves. We have a series of other small to large bees that nest on the ground or nest above ground that fall into other families. But probably those are the most familiar for most people."

Williams called attention to research led by his then graduate student, and now postdoctoral fellow, Maureen Page, who compared "the quality of honey bees at pollinating flowers versus the quality of other bees. And in general, we find that honey bees are sort of equal or slightly less good than many other bees. And the old adage, the jack of all trades is the master of none--the honey bee is really that jack of all trades. It's very wide in the number of flowers that it will visit, but doesn't tend to be particularly effective on any one flower visit relative to some of the other bees we have."

"The honey bee is particularly useful because it can be moved around and it lives in these very large colonies," Williams pointed out. "So it's a highly valuable agricultural pollinator. But there are a number of crops for which, if we look on the basis of an individual bee, the native bees are actually quite a bit better. A really great example of that would be alfalfa."

The alfalfa leafcutter bee "is a really effective pollinator relative to the honeybees at pollinating alfalfa," he told Flatow.

"So your bumble bee is sort of the lab animal, then," Flatow commented. "It's not a white mouse. It's a bumble bee."

Williams agreed. "It's become a pretty useful organism for studying things in the lab. I should say the other group that we work a lot with are mason bees and leafcutter bees. And because of the way they nest, they have been really useful for studying other sorts of questions. So there are a couple of groups that we work well with."

Williams also touched on the threats faced by native bees. In addition to pesticides (insecticides, fungicides, and herbicides), "they're threatened by the loss of reliable foraging floral resources," Williams said. "They are threatened by a set of emerging diseases. And this is, again, where the honey bee gets a lot of attention, right? This colony collapse may be resulting from certain viruses, but wild bees, native bees, also have some substantial problems with certain viruses and also other kinds of pathogens."

"And then a really big one is climate change. So we have to fully recognize that changes in rainfall and also changes in temperature patterns seem to be stressing bees in different parts of the U.S., for sure."

Flatow, whose colleagues say has "revived many an office plant at death's door," asked: "Can I plant a little patch of wild flowers in a pot or in the yard and really help out?"

"This is also one of these questions that's a complex one, but we'll try not to make it too complex," Williams said. "I mean, in general, planting flowers for bees is a useful thing. The one thing we'd want to be careful about if we were planting flowers in the yard is that we were also being careful about the use of some of these chemical pesticides. But I think also recognizing the importance of natural areas and broader stewardship of habitat for bees across the landscape is really important. And this tricky one with climate change, too--what are we going to do? We don't solve climate change with the sorts of things that we would do– small-scale actions--to help bees." 

"But we can do some things probably--providing shady spots, where they have what we call microclimates that are maybe protecting them from times where there are heat waves that are particularly problematic--things like that that could be useful."

Williams, who joined the UC Davis Department of Entomology and Nematology faculty in 2009, was named a Chancellor's Fellow in 2015, a five-year program supporting his research, teaching and public service. He was named a a Highly Cited Researcher by Clarivate Analytics in 2018, and a Fellow of the California Academy of Sciences in 2021.

A native of Madison, Wisc., he received his doctorate in ecology and evolution from Stony Brook University, New York in 1999.

Resources:

• Neal Williams, biography, Wikipedia
• Neal Williams lab, UC Davis Department of Entomology and Nematology
• Evidence of exploitative competition between honey bees and native bees in two California landscapes by Maureen Page and Neal Williams, June 2023, Journal of Animal Ecology
• Honey bee introductions displace native bees and decrease pollination of a native wildflower by Maureen Page and Neal Williams, December 2022, Journal of Ecology
• A meta-analysis of single visit pollination effectiveness comparing honey bees and other floral visitors by Maureen Page, Charlie Nicholson, Ross Brennan and Neal Williams, October 2021, American Journal of Botany