Science Friday
Hosted by Flora Lichtman
A new wildlife survey follows Lewis and Clark's route, 220 years later. And, cell and GPS data show how animals react to humans' presence.
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Hey, it's Flora and you're listening to Science Friday. In the early 1800s, Lewis and Clark loaded up their camping gear and journals and headed west to the Pacific, recording what they saw along the way. The expedition, partly about natural history, partly about future colonization, returned with a record of biodiversity in the early 1800s in the now United States. 200 and some years later, a new expedition is headed west to find out how wildlife populations have changed over the centuries. Dr. Roland Kayes and his team are traveling the same route, using camera traps and enlisting local scientists to document the wildlife along the way. Roland Kayes is the head of the Biodiversity Lab at the North Carolina Museum of Natural
Sciences, and he's on the line to give us an update about his trip and what they're finding. Hey, Roland, welcome to Science Friday.
Hey, great. Thanks for having me.
Where are we finding you today?
Right now, I'm basically in a van down by the river. We're on the Missouri River, which is most of the route that we're following. We're presently at a dam, Fort Peck Dam in Montana.
What are the days like? What are you doing all day?
Well, we are driving and kayaking along the Missouri River. So, we're hitting some of the more significant, more interesting, more beautiful parts of the river in canoes and kayaks, and otherwise, we're driving. And we're obviously looking for wildlife ourselves, but we're also collaborating with a team of scientists, over 100 scientists across the country who are running camera traps. And these cameras let us document in a systematic way what animals are living all along the route today.
What are the big questions that you're trying to answer?
Well, the big question is, is how is wildlife doing today? And then comparing that against what Lewis and Clark observed. So, they were meticulously writing down in their journals, all the animals that they saw, many of which they were, you know, shooting and eating along their route. We're not shooting and eating any animals, but we are getting them on camera, and we're able to compare, you know, how wildlife has changed really over the 250 years, right? We're up to our country's 250th birthday, and so this is kind of a long-term reflection of the state of wildlife.
What about the science of this? Is it scientifically meaningful if you happen to see the same animals that Lewis and Clark did 200 years ago?
Well, sure. So we're not the first ones to look at wildlife in North America since Lewis and Clark, right? There's a long, rich history of that. So what we're doing is using this as a time point to get a really good systematic survey across this region with the camera traps. And so that's one that we can use to compare from one region to another and from one year to another, you know, in recent time with camera traps. Lewis and Clark didn't have camera traps. So, you know, the comparison with what they saw isn't going to be, you know, super statistically robust. But there are some big, obvious patterns that we can see, you know, not only from the Lewis and Clark time point to today, but, you know, over the last few decades, the last few centuries. And so we're really trying to tell some of
those stories of, of how the wildlife's doing in our country and what have we done to help them and what have we done to hurt them? And what can we do sort of moving forward to maintain sustainable, healthy wildlife populations?
What are you seeing so far? I mean, have there been any, have you seen anything unexpected? Have there been surprises?
Well, so a lot of, you know, when you look at the big arc of wildlife, a lot of what we see today is, is good news. A lot of the animals that we see today are doing way better than they were 100 years ago. You know, we started in Pittsburgh where Lewis started his journey. And by the time he was leaving Pittsburgh, a lot of the big animals had already been shot out. And, you know, he observed flocks of passenger pigeon and not that long afterwards, those birds were shot out and they went extinct. He didn't even observe sandhill crane there. But when we were, we, when we visited a wildlife friendly farm north of Pittsburgh, we saw sandhill cranes every day. There were deer all over the place. The turkey were super abundant. And, you know, the reason this happened is because
we invented things like protected areas, right? There didn't used to be protected areas. We invented hunting regulations like bag limits and seasons. There didn't used to be those. And we did it at just the nick of time because, you know, we almost lost the American bison. We almost lost the black-footed ferret. There were a lot of species, even the bald eagle. We saw 15 bald eagles in one day on the Missouri River. And, you know, that's a species that almost went to extinction, was put on the endangered species act, another conservation measure that we invented. And it has now recovered and is now off the list.
That's really surprising because I think the story we hear all the time right now is that we're in the sixth extinction, habitat loss is this huge, huge problem. It just seems so dire for wildlife, but the picture that you're painting is more complicated.
It's more complicated. And there are, so that's kind of the more recent stories, right? And we're seeing some of that as well. We just drove through western North Dakota, where there's just oil infrastructure everywhere. And that's definitely hurting the wildlife, right? The populations are not able to live in that area that has so many oil rigs all over the place, so many roads, no habitat. We're moving next to the American Prairie Reserve, which we have almost no American Prairie left because so much of it has been converted to farmland and ranchland. And trying to find a way to have room for bison, for example, our national mammal, is still a big challenge. So what we saw 100 years
ago were challenges of too much hunting, overuse, unsustainable use. What we're seeing now is less that because we've learned how to manage that. And our society has agreed to follow these rules and find sustainable use of wildlife. Somehow, we stopped the destruction and we put a pause on it. And we invested public money in research to invent wildlife management. We invested public money in protecting areas, parks, national parks, national forests. Those are things that we really created in America in the early 1900s and mid 1900s. And that has allowed a lot of populations to come back to where they're much better today. What
we're running to now are problems of crowded planet, where can we have oil infrastructure? Can we have food production and still share the landscape with wildlife? So those are the challenges that we're looking at moving forward.
Are there any sort of big red flags for you, like animals in danger that really need our attention urgently that are not on people's radar?
Yeah, so along the way, we're visiting with local experts who know what's going on on the ground better. And we just visited with Dr. Amanda Cheeseman at South Dakota State University. And she was telling us more about prairie dogs, which it turns out have lost like 90 some percent of their range and are still being exterminated on public lands with public funds, which is just crazy to me that this native animal that, you know, what do they do that's so bad? They eat grass. And so people are concerned about the competition with cattle. We've got plenty of cattle, like, let's make room for these prairie dogs. And, you know, Amanda said, I think prairie dogs need a new PR team. And so we're trying to get in touch with a copy bar of PR team because they seem to be doing great. And we want to get them on the prairie dogs.
You need some memes, you know?
Yeah, right, right.
You need a prairie dog sitting under, like, you know, in a hot spring, relaxing.
You know, they might like the hot springs. I think you're hired for the PR team. We'll round up some prairie dogs and find a hot spring.
That's maybe the only job that's possibly better than the job I currently have, is the prairie dog PR team. Okay, best field moment so far?
Okay, so we've been doing these paddles along the river, you know, some of the important places. And we're paddling up the Missouri River at the mouth near St. Louis. And all of a sudden, this bald eagle starts swooping down on the river. So we're like, oh, wow, he's trying to get something. And he swooped twice and he didn't get it. And we're trying to see what was he going after. And, you know, we're paddling upstream and the water's coming downstream. And we realized it was a baby duckling that was getting attacked by this bald eagle. And this baby duckling literally jumped into our boat for protection from this bald eagle. So that was pretty incredible. I've never experienced anything like that before. So we brought the duckling back over to the shore. The bald eagle kind of got scared away by
our boats. And so the duckling survived the moment. But that was one certainly incredible moment we had.
You know, this is a very human powered approach to this question, but you're also an author on the science paper just out that takes a very different approach to tracking wildlife. Can you tell us a little bit about it?
Well, yeah. So we're using tracking data on animals, which tells us incredible detail about where they're going. This technology has gotten so much better over the last decade that we can really see how they're moving around. And in this case, we're able to pair it up with tracking data on humans, which has not been really widely available to really look at the details and the impact.
Unless you're big tech. But anyway, go ahead. Keep pleasing.
Right. Well, right. No. So it is available, right? But you've got to spend tons of money on it if you actually are going to get it. Like advertising companies will get it and use it. And so this was was one of the first times that we've been able to combine those two data sets together and look at, you know, how how wildlife are disturbed by people on the landscape. This comes back to sort of some of the so that sort of crowded planet problems of can we find ways for humans and animals to share space together? And, you know, sometimes animals can figure it out. Sometimes animals can adjust and habituate, but some animals and some animals in some places cannot. And so understanding where are animals still really freaked out by humans? And how can we manage that for their long
term conservation is really important.
How can people follow your trip?
Yeah. So my website, rolandkays.com. And we're also making videos. And so we'll be putting that out on my YouTube channel, Wild Animals.
Roland Kays is the head of the biodiversity lab at the North Carolina Museum of Natural Sciences. Happy trails, Roland.
Awesome. Thank you very much.
Thank you. We have to take a break. But when we come back, we'll talk more about that new study using big data sets to track our impact on wildlife.
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Up next, we're going to dig into that new study. A man in a van is one way to check in on wildlife, but there are other methods if you don't want to leave your climate-controlled office. My next guest is here to tell us more about her new study using big data sets from cell phones, cars, and GPS collars to track human-animal interactions. Dr. Ruth Oliver is an ecologist at the Bren School of Environmental Science and Management at UC Santa Barbara. Ruth, thanks for being here.
Hi, thanks, Laura. I'm thrilled to be here.
We're very glad to have you. So tell me, what was the question you were trying to answer with this study?
You know, our broadest question is how do humans impact wildlife? And, you know, humans are a complicated species, and we impact animals in various different ways. And so we were really interested in disentangling how we change habitats through modification versus our actual, direct, physical presence in those landscapes.
Right. So often, we look at how we've changed landscapes, like our buildings or our bulldozers, and how those affect animals. And you are trying to look at whether people are there or not.
Exactly. So there's a lot of great ecological theory. Like, we know this. We know that we impact wildlife. And there's all these great theories about how that might happen. Animals might fear us because they think we're predators, or they might be attracted to us because we leave out garbage that they might want to exploit for food. But we actually haven't been able to quantify those impacts on a large scale because we haven't, surprisingly, had the data on where humans are.
Yeah, this is what I want to talk about. I want to talk about how you did your study. So you used cellphone records and data from cars to see where humans are?
Yeah, so we were using anonymized aggregated cellphone device counts. So we're able to look at over space and time, a sort of relative proportion of how many people are physically present on the landscape.
Do you feel like this data is underused for science? Obviously, it's used for selling me things and tracking my body. But do you feel like it's underused for science?
I do. It was really surprising to me when we got into this study where I study wildlife. We have lots of information on where animals are. But how hard it was to get information on where humans are. And it's not that it doesn't exist, right? Because many of us are carrying mobile devices most of the time. But yeah, you're right. It's being used to sell us things. And it largely is not readily available for research applications.
What about animals? Do we have a lot of data on the movement of animals that you can use?
Yeah, we do. That's what's really, we're at this really exciting moment where we're able to put tracking devices on animals that can collect really detailed information on their movements. And there's so much power in that because we're able to understand how they respond in real time and adjust their behaviors and how they use habitats that can help us understand the mechanisms by which they get into trouble and eventually lead to population declines.
What were some of the findings? I mean, did any of the animal responses surprise you?
I think the most striking thing from our paper is yes, human presence has a large impact on a large proportion of the species we studied. But what was really interesting from our results were that, in general, animals responded more strongly to humans in less developed areas. And this maybe isn't totally surprising because it may be that those animals are less habituated to being around humans. But what it really means is that the way that we've been approaching this in the past, just looking at habitat modification, is not enough to understand our impacts as a whole.
Okay, so animals responded more strongly in less developed areas. Give me an example.
Yeah, so for example, we see that cougars shrink the amount of space that they use as the density of humans goes up, as more humans are present on the landscape. But they shrink it by even more when they're in a less developed area than a more developed area.
Yeah, that's really interesting. So it's like we have a bigger impact when we're not frequently around.
Yeah, exactly. An interesting exception to that were gray wolves, who actually expanded the amount of area that they used. And again, expanded it even more in rural areas. And we don't know totally why that is, but gray wolves have this really long history of persecution in North America. And so it could be that they're especially sensitive to humans and are having to cover even more ground to accomplish their sort of daily activities to avoid us.
I feel like these stories are always though, like, humans are taking up all the room and animals have to adapt. I mean, does this study suggest ways we might think about coexisting with animals better?
Absolutely. I think one of the things that we're most excited about from the study is that it gives us optimism that there are other conservation interventions that we could make that could help wildlife. You know, we've seen these big patterns of species going into decline, but we actually don't totally understand why. And our study is going down into this much more granular level at looking at how individual animals respond to various human activities. And what we're really interested is linking those two things so that we can understand the processes by which species go into decline. So we're really excited that our results might show that there's more nuanced, smarter policies that we could take that could help us share space. So thinking smartly about where and when we give animals space.
Dr. Ruth Oliver is an ecologist at UC Santa Barbara. She and her co-author Scott Yanko at the Smithsonian have a paper out in Science on this. This episode was produced by Annette Heist, and let me recommend that you put your cell phone data to another good use. Follow Science Friday wherever you get your podcasts. I'm Flora Lichtman, and thank you for listening.
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