The U.S. Fish and Wildlife Service has decided to list a bumblebee found only in Northern California and Southern Oregon as endangered under the Endangered Species Act. Franklin’s bumblebee hasn’t been seen since 2006. We hear more from Rich Hatfield, a senior conservation biologist and bumblebee program lead with The Xerces Society for Invertebrate Conservation.
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Note: The following transcript was computer generated and edited by a volunteer.
Dave Miller: This is Think Out Loud on OPB. I’m Dave Miller. A rare bumblebee that only lives in parts of Southern Oregon and Northern California is going to be listed as an endangered species next week. It’s called the Franklin’s Bumblebee, and it will be the first bee in the Western US to get that level of Federal protection, But there’s a catch. No one has seen a Franklin’s Bumblebee for 15 years. Rich Hatfield joins us to talk about this bee and the plight of pollinators, more broadly. He is a Senior Conservation Biologist and the Bumblebee Program Lead with the Xerces Society for Invertebrate Conservation, which is based in Portland. Rich Hatfield. Welcome to Think Out Loud.
Rich Hatfield: Thanks so much, glad to be here.
Miller: It’s great to have you on. What is a Franklin’s bumblebee?
Hatfield: Well, bumblebees, more broadly, are sort of large black and yellow creatures that inhabit our gardens and farm fields and wild areas. And we have around 50 species of them here in the United States. Franklin’s Bumblebee inhabits a very narrow range roughly from Roseburg over to Crater Lake down through Mount Shasta, that sort of narrow ‘Carrot Corridor’ that’s around 70 miles by 190 miles. So it once lived basically just in that Siskiyou area and it has a very distinct horseshoe shaped yellow pattern on its thorax and a little bit of white on its abdomen. But it’s a very relatively rare species, probably has the most narrow range of any bumblebee potentially in the world.
Miller: Do we know why that is, why it’s native habitat is so narrow?
Hatfield: We don’t. We have no concrete answer for that. The only sort of guess that we can throw at it, other people might be able to throw better guesses than me, but our best guess is that the Siskiyous are just a really unique ecosystem with some of the highest biodiversity that we find In North America. So there’s things happening there that we don’t have that we don’t fully understand and appreciate. And there certainly must be something that was keeping that species within that small narrow range because it shares that range with 20-30 other species that have much larger ranges. For one reason or another.
Miller: Is it possible, for example, that it has some kind of favorite flowers that primarily exist in that area?
Hatfield: It could be. This is a little bit of a caveat and that there’s only probably, less than 500 observations of this species ever in the known sort of human history, but one of the things we understand best is its association with flowers. So when we did observe it, it was seen visiting one species of flower or another, it likes California Poppies, it likes Horsemint and some of these other flowers. So it’s probably not a flower. If it was something it would more likely be a nesting requirement or an overwintering requirement. And those are areas, honestly, of bumblebee ecology that we know very little about for most species. So that could be a limiting factor for sure.
Miller: What are the reasons to the extent that we know them for the population decline of this bee, in particular?
Hatfield: It’s not something we were able to study. This decline happened really rapidly in the late 1990s. The leading hypothesis for the decline of this particular species is that it contracted a pathogen and it’s a fungal pathogen. It’s believed that that pathogen was distributed and amplified by commercial bumblebees in North America. So just to expand on that a little bit, you know, as human beings, we’ve learned to like tomatoes and we like to eat them year round. So because of that, we grow a lot of tomatoes in greenhouses. And bumblebees are very good pollinators of tomatoes. And so humans essentially created a novel solution to a novel problem and learned how to take a wild animal and essentially put it in boxes so that they could be shipped to greenhouses for those pollination services. Honeybees, for instance, aren’t very good pollinators of tomato plants, but bumblebees are, because they can do something called buzz pollination. So it’s believed, in that process of forcing animals to reproduce in labs and then shipping those boxes all over the country, that potentially a pathogen was spread to
the species and caused a really rapid population crash. But it’s also important to note that while this disease was probably a major factor, if this species was not also dealing with things like habitat loss and pesticide use, perhaps it could have sustained a disease outbreak. But when you throw it sort of on top of all the other factors that bumblebees and other pollinators are facing, it became essentially the straw that broke the camel’s back.
Miller: This just never ending onslaught of human activities. The anthropocenes, just all these things added together and it seems like it’s hard to disentangle them. I want to go back to one thing you mentioned, ‘buzz pollination,’ which I guess as you’re saying, European Honeybees don’t do that. What is it?
Hatfield: It’s a pretty neat thing to see and observe. There are some species of flowers that have their pollen essentially fused inside their anthers. The anther is the male part of a flower that releases the pollen. That’s what bees are often targeting when they visit a flower and for most species of plants out there, the pollen’s just readily available, and a bee can go sort of use the cones on their legs and put it on their bodies and put it on their legs and then fly to the next flower, but there are some flowers that have their pollen sort of locked inside. And the only way to get that pollen out is to shake it. And it requires a fairly specific frequency. And you can hear this if you’re say, in your garden, in your backyard and you go back there and you’re watching bumblebees visit your tomato flowers, you can sort of hear the sound that their wings make as they fly in between flowers, which is often a low buzzing sound. Then they’ll get to the flower and they’ll latch their mouth parts onto the flower itself and then vibrate their wings in a very sort of high frequency, it’s more like a [Hatfield vocalizes a high pitch] ‘bzzt, bzzt, bzzt,’ sound. That’s when they’re actually doing that buzz pollination and they’re shaking that flower so that the pollen comes shooting out of it. You can actually see videos of this. Actually, an electronic or an electric toothbrush is about the right frequency. If you go do this on your tomato plants, you can actually see the pollen coming out of the anther, it’s kind of like a salt shaker...
Miller: Huh. They turn on their little dremel bit and then they shake the pollen out.
Hatfield: [Laughing] Yeah, exactly.
Miller: What does…
Hatfield: Bumblebees are really good at this, and most other species of bees aren’t very good at it.
Miller: What does it tell you that this particular bumblebee has not been seen since 2006?
Hatfield: Well, it’s concerning, primarily, it certainly indicates that the species has become a lot more rare than it used to be. But I think an important caveat there is that the area that I described from Roseburg to Crater Lake, down through Mount Shasta, while there is a fairly large transportation corridor in I-5, and a few towns, it’s largely a pretty remote and wild area full of wilderness areas that aren’t frequently visited by people and even less frequently visited by people that are carrying insect nets and looking for bumblebees.
Miller: Would we even know what to identify if they happened to be looking for bees, right?
Hatfield: That’s right. Most people just think of ‘bumblebee’ as one species. The idea that there are 50 species in North America would be news to a lot of people, I think. So while it’s concerning, this listing decision to add it to the [Endangered] Species Act will raise awareness. That will allow me, for instance, to do educational workshops for people that might be interested in helping and to teach them how to identify the species or what to look for. And then we can send them out into these remote areas with cameras and nets and hopefully find this species so that we can begin the process of recovery.
Miller: Will this Federal listing as endangered, the highest level of protections under the Endangered Species Act, will that lead to changes in the way this land, this habitat, is managed?
Hatfield: Potentially. Right now, since we don’t have any known locations and the Fish and Wildlife Service declined to designate Critical Habitat, it’s really unclear where that might happen. But if we were to detect this species, they find a population somewhere in the Siskiyous. Then that region would become some sort of high potential zone. It would be the sort of model that the Fish and Wildlife Service used for a bumblebee Species that’s been listed in the Eastern United States called the Rusty Patched Bumblebee. And within that zone, we would have to do surveys to determine that any project with a Federal nexus that was either funded by the Federal Government, or it was happening on Federal Land to make sure that project wasn’t going to impact the habitat or the species itself.
Miller: Let’s turn to broader issues involving pollinators of all kinds. How are they doing overall?
Hatfield: Well, it’s a hard question to answer. I think when most people think about our understanding of biology, they think about how well we understand mammals and birds, which are very well studied. There’s lots of people working on them. They’re large, they’re conspicuous, they’re easy to follow. Here in North America, we have 3,600 species of bees, at least, likely more than that. And most of them are not well studied. in terms of understanding their population, how well their populations are doing. bumblebees are probably the best studied of them. And the research that we’ve done suggests that around a quarter of them are facing some degree of extinction risk. So, that’s not great news, that suggests that these animals, that are helping to provide food for us, as pollinators -- one out of three bites of food that we eat comes from plants that are pollinated by bees, but they’re also feeding wildlife, grizzly bears and song birds and small mammals eat berries and roots and nuts and we wouldn’t have those things without pollinators. So, you know, when you hear that a quarter of these animals that are doing this important work are in decline, that’s pretty concerning.
Miller: What are the various ways that bees are being affected by climate change right now?
Hatfield: It’s again, another one of these ‘straw that breaks the camel’s back’ situations. We’ve talked about the effects of pesticides we’re using through large portions of our landscape.
We’re using highly toxic insecticides that are certainly affecting the bumblebees and other pollinators. We were turning habitat from meadows and prairies into farm fields. So that’s habitat that used to bloom for 20 weeks, now blooms for two weeks. So we’ve done all these other things and now we’re adding climate change. We’re adding extreme weather events. Here in Oregon, we had temperatures of 115° earlier this summer, which is well beyond the thermal tolerance for something like a bumblebee. There’s no way they could keep their nest cool enough in that situation. All of these things are just having tremendous effects, they’re also just mostly cold weather adapted species. So as the climate warms or changes that’s going to affect them. One of the major effects that we’re seeing is this phenological shift. So by phenology, I mean, sort of as plants emerge, then the bees will also emerge and that’s happening a lot earlier than it used to. Plants are blooming before they ever have before. We still have yet to see whether bumblebees and other pollinators were able, will be able to match that in terms of how early they emerge. Can they match the timing?
Miller: Can they sync up and wake up at the right time, in a sense?
Hatfield: Exactly. And then if it’s starting earlier, will it last long enough to allow bumblebees to finish their fairly long lifecycle? They need 12-20 weeks of bloom time in order to reproduce. So it’s a fairly long life cycle. And the other thing that’s happening as these plants are blooming earlier, we get these early springs, but then sometimes we’re getting these really dramatic ice storms that happen after bees are out and after flowers are blooming and then those flowering resources disappear and who knows what happens to the bees when winter returns for a week. So it’s really creating a lot of problems for bees.
Miller: Rich Hatfield, thanks very much for joining us today.
Hatfield: Thanks so much for having me. I really appreciate it.
Miller: Rich Hatfield is a Senior Conservation Biologist and the Bumblebee Program Lead with the Xerces Society for Invertebrate Conservation, which is based in Portland. He joined us to talk about the Franklin’s Bumblebee, which is going to be officially listed as an endangered species next week. Coming up tomorrow we’re going to revisit our conversation with the Poet and Essayist Ross Gay, his most recent work, The Book of Delights is true to its name. It’s a celebration and exploration of joy even in a world full of sorrow. It was chosen for this year’s Multnomah County Library Community Reading Project, ‘Everybody Reads.’ Our production staff includes Julie Sabatier, Elizabeth Castillo, Rolando Hernandez and Senior Producer, Allison Frost. Nalin Silva Engineers the show. Our Technical Director, Steven Kray and our Executive Producer is Sage Van Wing. If you don’t want to miss any of our shows you can listen on the NPR One App on Apple Podcasts or wherever you get your podcasts. Our nightly rebroadcast is at eight p.m. Thanks very much for tuning in to Think Out Loud on OPB and KLCC. I’m Dave Miller, we’ll be back tomorrow. Think Out Loud is supported by Steve and Jan Oliver, the Rose E. Tucker Charitable Trust and Ray and Marilyn Johnson.
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