Bees Are Not Optional
It's Pollinator Week, and we're talking to USGS scientist Sam Droege about the tremendous importance of native bees and pollinators in general, and how you can lend a hand to these tiny titans.
Like eating fresh fruits and vegetables? Think agriculture is important to our society? Then you'll want to pay attention to this CoreCast. (original recording: June 25, 2009)
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Bees Are Not Optional
Catherine Puckett: I'm Catherine Puckett and I'm with Sam Droege here at the USGS made a bee lab in Lowell, Maryland. And if you look around, you will see boxes of bees here and there, some wasps, bees being looked at under microscopes or on some slides, I think over there. That's what you were doing a minute ago.
And, can I pick this up?
Sam Droege: Right.
Petri dishes full of dried specimens that are going to be achieved after we finished with them.
Catherine Puckett: And do you look at every one of these bees?
Sam Droege: Oh yes, yes.
Catherine Puckett: OK.
So, Sam works on native bees and you were saying a little while ago that USDA pretty much studies honeybees, the agricultural workers.
Sam Droege: Right.
Catherine Puckett: And the USGS, the Department of Interior, pretty much looks at native things.
Sam Droege: Right.
Honeybees are like the chickens of the bee world. So, the ornithologist don't look at chickens, USDA looks at chickens. Ornithologists look at native birds and we do the same thing, we look at the native species of this.
Catherine Puckett: A point that you made was how small that these bees are. Just wonderfully colored, little, tiny bees in many cases, and I know that that's surprised me. So, talk a little bit about that, because they're almost invisible, I think, to us who are not out there looking.
Sam Droege: Right.
So, if you think about it, there're a lot of flowers out there. A lot of flowers have little tiny, tiny blossoms. Little tiny blossoms have little tiny bees going to them, so it makes sense people, again because they're not stinging them, they're so small, they don't match the notion of this looks like a bee, then what happens is that they get lumped as a bug, for example.
But almost all of them are soil nesters; and they're nesting in your lawn in any open bare area, and sometimes, in between the grass plates. And a lot our diversities is in the small species. So in Maryland, as an example, there's probably somewhere close to 450 species of bees.
A bunch of which, we're not quite sure of yet both because we haven't done enough investigations and because some of these species groups, we're still are learning what the actual names are for the species. We're at a very low level in our understanding of bee populations. We don't even know the names of some.
And if we look at that, probably, well over half are these very small, under a quarter of an inch bee species.
Catherine Puckett: How did you get interested in native bees, in particular?
Sam Droege: Well, I guess I've always been interested in bees. I've always been interested in insects. I've collected when I was a student for years, and I've always retained that interest in insect populations.
But more importantly, when we're looking at what's important for us to be surveying and collecting and getting information about, it was clear that we had a situation where there were declines or perceived declines in populations of native bees.
But on the same time, we had a big lack of information about those declines. So there was no bureau of census of bees that had a lot of information that had a lot of information that we simply just had to crunch the numbers. There were no numbers to crunch.
That's the role that I play, developing ways to generate those numbers. That's what we've been working on the past few years.
Catherine Puckett: Why are native bees important? I know that on your email, you have a little tagline that says, "Bees are not an option."
Sam Droege: Right.
Catherine Puckett: So, I want to know what that means.
Sam Droege: Well, they actually aren't..
In the worst-case scenario, let's say all bees were eliminated. Let's say that ...
Catherine Puckett: Native bees and honeybees?
Sam Droege: Yes, just everything, all the bees were gone.
What you would find is that somewhere between 30 percent and 60 percent of our plants would ultimately disappear because they require bees or other kinds of insects, but primarily bees, to do their pollination; no pollination no seeds, no seeds no next generation kind of thing. And that includes our agricultural crops too. So we have a number of our fruits are, orchard crops or vine crops, tree crops, brambles, they all require bees to pollinate.
So at the most simplest level, we would just lose a whole variety. A large chunk of our environment will disappear because of the plants, not because bees were gone per say but because they would not be pollinated by bees.
Catherine Puckett: So, they'd essentially be sterile. They'd have no way, I mean because they can't ...
Sam Droege: Right, yes, exactly.
They need some insect to move pollen from a female flower to a male flower.
Catherine Puckett: The male flower, OK.
Sam Droege: Different species of bees have different requirements like any animal. So, for example, some bees are especially designed for to sandy areas. A lot of bees are pollen specials, meaning that one species of bee is going to one species of plant or more generally, in one genus of plant, so there's specialists on cactus, there's specialist on willow, spring beauties. There's a whole list, a very surprising list–hollies–that have a tight bee-plant interaction.
So, if you lose a lot of diversity of plants or you lose your diversity of ecosystems then your diversity of bees, like almost any plants and animals, would go away down too.
Catherine Puckett: OK. It is National Pollinator week and most people don't even know that there's a National Pollinator week, so why should they care about native pollinators?
Sam Droege: Well, I guess there are a couple of things. One is you should care because if you like apples, you should care a lot; if you like tomatoes, you should care a lot. If you want squash or cucumbers or pecans, those kinds of things, hey those all require bees so you're not going to have a wide variety of things to eat if we're actually to lose bees. So there's a reason to care.
The other is just a diversity of bees. It's another diverse group, 4,500 species just in North America alone. They're doing all kinds of different things. Their evolutionary tree goes back 200 million years, so we're playing with systems that have very ancient lineages.
There're all kinds of very interesting life history things; it's just like, "Why study birds?" Most of those birds, indigo bunting, we're not eating them, they're not even something that's important to us and we have an affinity and a love of their study.
The problem with bees, they're so small. People don't see them. It doesn't register as something to look at; there's no field guides to these bees. If bees were the size of chickens, I think, we'd pay more attention to them.
Catherine Puckett: I think so, too.
You talked a little bit earlier about how the everyday citizen could protect bees, native bees.
Sam Droege: People can do a lot.
I think people have this perspective that conservation and protection of plants and animals occurs only in very far away areas. But for things like bees, they work at a very small scale. So a yard is something that can be done very effectively.
If your lawn, for example, can be converted from primarily grass, which is not something that's attractive to bees, to something that has a lot of clovers. Lots of other kinds of flowers, low-growing things that still can be lawn and can be kept, and the neighborhood will still be happy with you. But now becomes a place that is rich in the small tiny bees, that are non-stinging, that are attracted to those kinds of places.
In people's yards, there are many, many kinds of bees. People are just not aware of them because they're not stinging them. They're not these colonial things. They're not the wasps, the "yellowjackets" that nest in the ground. So, you can convert it that way.
The other is by generally planting native species of plants. So, both shrubs, herbs, flowers and the local plants from the region will do the trick because those are all geared towards being pollinated by the local bees and the plants. Then if you're doing more exotic species of plants, then you want to make sure that they're not highly drive, they're not been bred so much that they're all color and no nectar and pollen.
Basically, if you want to conserve these, you actually have a lot more opportunities than you do for other groups. So, even for butterflies, when people now and it's popular to populate and put in a butterfly garden. But if you actually look what're in your butterfly garden, it's far more likely to be bees that are the primarily respondent, the primary beneficiary of adding all these butterfly plants.
It turns out that bees are much better dispersers and they can find these new resources a lot better than butterflies. We know that even in the downtown on the National Mall, that we got lots and lots of different bee species in these gardens that are planted around the Smithsonian and we get almost no butterflies, for example.
Catherine Puckett: So, just because you live in New York City and you might have a rooftop garden, you shouldn’t discount.
Sam Droege: Right.
Bees occur. There is a study, I don't know if it's been published or about ready to be published, in Chicago that shows that there are quite a few bees that occur on these new green roofs and these high gardens in quite tall apartment buildings. So, even something like that can have bees species, where again you're just very unlikely to have almost any other kind of plant or animal colonize those areas, but bees, not a problem.
I don't think people are aware of how many bees are out there. We have these concerns that there are declines, but whenever we do these studies, we're catching not one and two bees at a time; we're catching hundreds, and sometimes thousands of bees.
Catherine Puckett: In a day?
Sam Droege: In a day.
Catherine Puckett: Wow.
Sam Droege: So, it depends on the place and the trapping technique, but there are very high densities of these out there still, and so one of the notions I have, still we don't have the numbers because that's where we're going, is that unlike my expectations initially, that we're running across a lot of rare bees. We're getting new records; we're finding all kinds of new information so the world hasn't completely collapsed around the bee issue.
What we really don't know is what's going to be coming up in the future and what are comparisons are in the past because we have no past records, but when we go out there, we still find many, many bees. If you look at around your land or you look out on a meadow, there are many flowers. Many flowers equal many bees.
If you have a little bee, it doesn't take much to feed their young because they small amounts of pollen and small amounts of nectar because most environment support huge number of bees, thousands upon thousands. Your yard could have easily a hundred-plus bees in just a small suburban area.
Catherine Puckett: OK. Great.
Sam Droege: Sure.
Catherine Puckett: So much.
CoreCast is a product of the U.S. Geological Survey, Department of the Interior.