I THINK I MIGHT have a new favorite gardening tool, thanks not to a horticulturist or even a botanist, but to the inspiration from a zoologist, specifically a mammal expert, Dr. Roland Kays of North Carolina State University and its Museum of Natural Sciences.

In his compelling, unexpected new book, “Candid Creatures: How Camera Traps Reveal the Mysteries of Nature,” we get to see the hidden world that scientists have discovered using what are maybe more commonly known to some of us as trail cameras. We learn about the populations and behaviors of critically endangered species worldwide—and also about others you’ve seen in your own backyard.

Yes, there are both chimpanzee (above) and raccoon selfies in “Candid Creatures”—illustrated with more than 600 photos that Kays has curated from the work of noted research colleagues around the globe. Kays, a co-author of the field guide “Mammals of North America,” took time to explain to me what this tool that only relatively recently became field-worthy is doing to revolutionize science, and conservation—and what it can do for our own understanding of the immediate world around us, too.

Read along as you listen to the June 13, 2016 edition of my public-radio show and podcast using the player below. You can subscribe to all future editions on iTunes or Stitcher (and browse my archive of podcasts here).

my camera-trapping q&a with dr. roland kays

Q. Congratulations on the stunning new book, from Johns Hopkins University Press. Wow! There are millions of these types of images out there in the world, but you curated them to create the book, yes?

A. Every camera trapper out there has a folder of “greatest hit” images. So my goal was to round these up. Many of them are hidden away on someone’s laptop in Malaysia, and it’s one of the fun things we like to do when camera trappers get together—we like to show off, and show each other our favorite pictures.

These are collected from thousands, hundreds of thousands, sometimes millions of images—depending how big the research project is. They are already sort of culled down, so to write this book I started with the primary literature, and would read journal articles or reports from different people around the world. When I found something interesting I would write them and say, “Hey, I want to talk about your work. Would you have some pictures you could share?” And they almost always did, and it was really look through all those.

Q. I loved it, and it was the ultimate curatorial job.

A. It was really fun to get an email with a bunch of pictures from Iran, or Malaysia, or different places around the world.

Q. I think if I say “field camera” or “wildlife camera,” people probably think: It’s a tool for deer hunters. But these cameras have changed science, haven’t they?  [Above, deer caught in a camera trap  while feeding on apples, with a flying squirrel in the background; photograph by Hailey and Logan Lehrer.]

A. They really have. Camera technology has really gotten better, and camera traps go back to the early 1900s, when people would tie a string to a giant, big-format camera. Every advance in camera technology, whether it’s 35MM film or electric flashes, has allowed us to do better with these automatic units in the field.

But when we finally went digital, which didn’t happen until about 2008, all of a sudden it really exploded, because we weren’t constrained to a roll of 36 exposures of film. One herd of deer can shoot that out in a second. All of a sudden there was so much more—and we’re still learning more of what we can do with them.

Q. Until I read your book, I thought they were only used for capturing images of mammals on land, but that’s not the only place, either.

A. We get birds on the ground. Some of my favorite images—I’ve got one bat species in the book, and there are some amazing pictures where people actually get pictures of vampire bats feeding on other animals, which is amazing when I saw that.

Mostly it’s mammals, but some of my favorite pioneering work that’s happening now for the first time is that people are starting to put them up into the rainforest canopy, up into the trees. There is one study in Peru: You think about the rainforest in Peru, and I think of the canopy as monkeys and toucans and parrots and all these things that are out there in the day, but they got nine times more pictures at night—of things like kinkajous and night monkeys and weird porcupines and possums and such. Still many interesting things to be learned out there.

Q. I learned many things in this book (including that a baby wombat is called a joey, which made me laugh uncontrollably). I mean, you knew but I didn’t.

A. Did you notice that the pouch is backwards on the wombat as well? [Above, a wombat’s joey peering out of its mother’s backward-facing pouch; Georgeanna Story photograph.]

Q. No, still so much to learn.

A. So they don’t fill up with dirt when they are digging.

Q. Oh, brilliant, of course. That would be a disaster. And I learned that the world’s smallest deer lives in South America—the pudu. It’s really small.

A. It’s tiny. [Laughter.]

Q. It looks like a mini-deer. On a much more important scale: What are some of the discoveries scientists have made with the traps? Any new species or what?

A. I don’t know of any that have been discovered simply through a camera trap, but there was one where they thought they had one, some kind of new carnivore from Southeast Asia. But then once the pictures got out and they looked closely, they realized it was actually a type of squirrel that they had from a funny angle—and no one had seen this squirrel very much, so it was still neat that they got it.

There are some that were thought to be extinct, like the Sumatran ground cuckoo, and then they got some camera-trap pictures of it. And the Angolan giant sable antelope was thought to be extinct, and was rediscovered.

But I think sometimes just one photograph can be a discovery. Hey, the ground cuckoo is still alive: That’s awesome. But other times, it comes more from the numbers, and analyzing the data later, and putting dots on a map, for example. Most of what we know about where tigers still live today comes from camera trapping—which forests have them, and which forests we’ve lost them from.

And then also starting to look not just if tigers are there or not, but how common are they? How many tigers are there; counting them, and starting to compare that, and say: Why are there more here than over here, than over here? Is it aspects of their prey, or the landscape, or the habitat, or the road density? [Above, a tiger in India after a mud bath; photograph by World Wildlife Fund.]

A lot of the end goal for all this is to find ways that humans and animals can share the planet better.

Q. There were a lot of solutions-based applications that the traps have been put to use for. Like what might sound simple, but is not simple: how to figure out how to allow animals to cross a road more safely. And that doesn’t just impact who lives or dies, but also has to do with genetics, yes?

A. Yes. When a highway goes in, what we don’t want to have happen is that it fragments a population of animals on either side so that they can’t exchange their genes any more. Then you could start to worry about restricted gene flow, inbreeding, and eventually the population could go extinct, just because they can’t get any fresh blood in.

By maintaining this connectivity between there, if you can get animals to move back and forth without risking the road, risking getting hit by a car on the road, then you will have more healthy populations on both sides of the road.

Things like underpasses are the most obvious way. There has been a lot of research putting cameras on the underpasses and see what’s using it—or what’s not using it. Sometimes what’s not using it turns out to be more important, and then you have to find other options for those animals.

Q. There was some large animal—I cannot remember who it was—who actually doesn’t mind the tightness of the underpass. There were some surprising creatures coming through underground passages in the photos in the book. [Above, three young cougars being led through a culvert by their mother. Photograph: Tony Clevinger.]

A. Cougars are an example of a pretty large animal who actually prefers the tighter quarters. Other animals, like pronghorn antelopes—they’ll occasionally use them, but they’re very shy and get nervous, and are really an open-country animal. They’ve had to build these overpasses to help them get across the road, and they’ll use them quite readily.

Some of my other favorite examples were tree-climbing animals, like monkeys or possums in South America, that don’t like going to the ground at all, and when they do they’re kind of slower on the ground, so they’re more likely to get hit.

So they just strung a rope over the road—or a rope ladder—and these animals would climb over the top of the road on this rope, rather than go underneath.

Then in North Carolina, they have flying squirrels that were getting fragmented by a road, and they just built a launching pad up on a pole. [Laughter.] They got pictures of this flying squirrel running off the end of this launching pad that’s just a big telephone pole with like a horizontal diving board on it. He just runs across it in the middle of the night and launches off and glides over to the other side of the road.

Q. What other kinds of things does it have application to—different industries like agriculture, for instance, that have to do with the outdoors?

A. Certainly things like hunting and forestry and trapping—these kinds of extractive industries, and trying to find ways they can be done sustainably with wildlife populations. That’s a big theme running through the book.

And other things like development, like how close in will animals live to people. Even in our suburban areas, we have animals moving more and more into the suburban area, especially over the last decade.

So looking at how animals have habituated to humans and which species are doing this over time is a really interesting question.

Q.  The logging industry was one of the ones cited in the book. We hear a lot in the news about agriculture and grazing areas, and how that impacts on wild spaces and populations of native animals. I assume some of the inferences drawn from the traps help in the management of those types of spaces.

A. If you have an area that’s going to be converted to oil palm, or that’s going to have natural gas drilling out there—so what’s the impact on the wildlife? The camera traps are one of the best ways to do it, because the other option is you have to sit there and wait for the animals to go by [laughter], or maybe do the census in a car.

But the animals are going to hear the car, and if you walk—animals are really good at seeing and smelling and hearing us before we see them, so they run away, so you don’t see them, and they’re not as effective. Whereas you can put one of these little silent camera traps, strap it to a tree and leave it there for a month, and you get a record of everything that walks by.

Q. There was a lot of discussion in the book about evaluating the effects of hunting in public parks, for instance, and comparison between parks that have hunting and don’t have hunting and the patterns of animals. That was kind of wild.

A. That was a project I was involved with, and we actually just published those results. We wanted to look at the effect of hunting and hiking on wildlife communities.

Q. Right, not just hunting, but hiking also.

A. That’s our question, so the next thing we had to figure out is how can we use cameras to answer that question? So we put cameras on trails, near trails, and far from trails—so we could actually compare what animals avoid the trails and were only seen way off trail. And the other thing was that we got a count of the people, so we could see how intensely a trail was being used by hikers.

On the other side what we did for hunting, is we looked for parks that were near each other; two parks, pairs of parks—one that had hunting, and one that didn’t. So that way we could compare and see it was the same elevation, the same forest type, the same part of the country or the state. So they should have the same wildlife, and the main difference is that one’s hunted and the other isn’t.

We should be able to detect big differences.

The good thing we found was that neither hunting nor hiking was that important to the 12 different wildlife species we were able to look at. Things like deer, squirrels and raccoons, which are actually the most-hunted species, were a little less common in the hunted areas. But they were still pretty common; there were a lot of them.

This shows us that these managed lands—where hunting in regulated, and the wildlife managers are setting rules to make sure that it is sustainable. This suggests that they’re doing a good job of that.

The thing that was a little bit of a surprise was that the strongest impact of hunting was an increase of coyotes [below].

Q. Huh.

A. If you’re shooting them, why would there be more of them in there? Why would we be getting more pictures of them? We don’t have a for-sure answer yet. One of the ideas:  Coyotes’ abundance is regulated by their social system. You have an abundant pack, and they keep out the floaters. There are always these young animals floating around, running around, trying to find a territory. And when you lose a member of a pack they’re not howling any more, they’re not scent-marking any more, and it’s an open territory.

The idea is—and we don’t know for sure if this is what’s going on—but we think that if you remove one, you get three or four coming in, and try to take over that spot. So you end up having more animals in there. That would equilibrate eventually, but if you have another animal removed, and another animal removed—you have this constant chaos, this magnet for young coyotes looking for a territory.

Q. Opportunists. [Laughter.]

A. Totally.

Q. It’s probably a lot of years since you put out your first camera trap; you’ve been doing this for a very long time.

A My first cameras were when I was in New York, around 2000.

Q. You were in Albany then.

So I’m going to give this a try, so I want to transition to talking about the sort of DIY-ish part of the subject. What’s prompted me is that I seem to be enjoying living inside my 2.3-acre 8-foot fence, which keeps out coyotes, with a bobcat…

A. Oh, wow.

Q. …and a gray fox; both adults. They’re with me since maybe the winter, certainly for a number of months. I think maybe it was because I fed birds—and I don’t know if this is the reason—but I wonder if that was easy pickings of rodents and also birds. I’ve taken down the bird feeder. [Laughter.] [Above, bobcat photo from Roland Kays’s recent research project.]

I’m interested to know more—and I don’t want to be foolish and go charging around and disturb anybody, but it seems like an opportunity to learn. And I should say my small piece of land is surrounded by thousands of acres of state park, wild land.

So what do I do—how many traps do I need? How do I get started?

A. Just buy a camera trap and put it out. [Laughter.]  

There are lots of camera traps, and there is a website that has good reviews of them, called TrailCamPro dot com. They keep up with anytime a new camera comes out.

When we run cameras, we tend to stick to just a couple of models that are maybe a little bit higher-end, because we need research-grade data. They have very fast triggers, and take pretty good pictures.

The one that we like to use, the high-end one is called a Reconyx, and then we also like the Bushnell cameras. We’ve been experimenting with the high-end Moultrie cameras, too. [Above, A Reconyx and a Bushnell camera; photos from corporate websites.]

It is true that you get what you pay for, and I wouldn’t buy whatever the cheapest one is; you’ll probably have problems with that.

There is this new camera that I have just been experimenting with that’s not meant as an outdoor trail camera.

Q. I watched your crazy video—you’re hacking an indoor camera and it was fabulous, with like a Rubbermaid or Tupperware little box. [Laughter.]

A. I just put it in a Tupperware, and cut a hole in it, and it’s been holding up great. If it breaks it’s my own fault, but I’ve had it out in some pretty big rainstorms.

What’s great about this camera is that it sends you the data live through your own wi-fi connection.

Q. So for a backyard person whose wi-fi extends around their property, that would be interesting–like a live feed.

A. It’s really fun. I got a deer walking through my front yard today. I’ve got this deer who’s been coming to my yard that’s a partial albino; they call them piebald deer. It’s got like a white belly, and now I’ve got other people in the area sending me images, and I’m starting to piece together the home range of this animal using backyard cameras. It goes over a surprisingly large area.

And that’s called the Blink, and I’ve got a video of it.

Q. Yes, it’s like when my farmer neighbors hack different devices when they can’t find the right equipment, or it’s too expensive.

In the book, the researchers were sometimes using two cameras, to see both sides of an animal that’s patterned, and be able to identify it.

A. The paired setup is kind of a special case for people working with animals that can be uniquely identified, like a tiger or jaguar. If you can identify animals from their stripe or spot patterns, there’s a lot of interesting extra cool things you can do with that data.

You can estimate animal density, and look at animal survival over time. The trick is: the right and left sides are not symmetrical, so you need to get pictures of both sides of the animal, with two cameras facing each other.

Q.  So I was wondering if I had to do that, or what I had to do. [Laughter.]

A. No, you don’t have to do that. We do have a citizen-science project called eMammal. That’s actually how we surveyed all the parks we were talking about earlier. It wasn’t me or my field assistants going out there, it was a couple of hundred volunteers, who were running cameras in state parks, but we’ve also worked with a couple of hundred people here in Raleigh, and in the Washington, D.C., area, having them run cameras in their backyards behind their house.

You could probably get permission from the state park that you live next to run some cameras there for comparison, and the nice thing [with eMammal] is that it sends all the data to a central place, so that we can start to make comparisons, and you can see how your site compares to other sites.

We have some cameras we loan out locally, and we have a new statewide program across the state of North Carolina that we’re excited about starting later this year. But also if you have your own camera and want to sign up and share things from your site, we would welcome that to try to broaden our knowledge base.

In that case, it would have to be a decent camera trap, not a cheap one, and we also ask: Don’t throw out bait.

Q. Well, you might be meeting my friend the bobcat; you never know. I might be sending you some pictures.

more from dr. roland kays

• Roland’s website
• eMammal, the citizen-science project with Smithsonian Institution
• Roland’s just-published research on the effect of hunting and hiking on animals in protected Eastern forests
• Our previous interview, about his field guide, “Mammals of North America”

enter to win ‘candid creatures’

I’LL BUY A COPY of “Candid Creatures” by Dr. Roland Kays for one lucky reader. All you have to do to enter is answer this question in the comments box at the very bottom of the page, below the last reader comment:

What animal are you most curious about, whether one you’d like to see in your own neighborhood, or farther afield?

I am a fan of macaque monkeys (below), though I have never met one–and don’t expect to catch one on-camera in my backyard. Their intense curiosity just delights me. Closer to home, I suppose I love the gray fox and the bobcat–for the glimpse they provide of some of the same moves (especially when hunting) that I’ve seen in domesticated canine and feline species. Weasels are impressively fierce (and strangely built); black bear so massive yet so agile–a surprising combination when one races up one of the old apple trees. I suppose the only animals I’m not so eager to see in the garden are woodchucks and rabbits (deer are excluded by my fence).

No answer, or feeling shy? Just say something like, “Count me in,” and I will–but answer is even better.

I’ll select one random winner after entries close at midnight Sunday, June 26, 2016. US only. Good luck to all.

prefer the podcast version of the show?

MY WEEKLY public-radio show, rated a “top-5 garden podcast” by “The Guardian” newspaper in the UK, began its seventh year in March 2016. In 2016, the show won three silver medals for excellence from the Garden Writers Association. It’s produced at Robin Hood Radio, the smallest NPR station in the nation. Listen locally in the Hudson Valley (NY)-Berkshires (MA)-Litchfield Hills (CT) Mondays at 8:30 AM Eastern, rerun at 8:30 Saturdays. Or play the June 13, 2016 show right here. You can subscribe to all future editions on iTunes or Stitcher (and browse my archive of podcasts here).

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