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What Happens When Animals Cross the Road

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Thursday, April 18, 2024

As highways encroach ever further into animal habitats, drivers and wildlife are in greater danger than ever. And off the beaten path, decaying old forest roads are inflicting damage as well. “Roads are this incredibly disruptive force all over the planet that are truly changing wild animals’ lives and our own lives in almost unfathomable, unaccountable ways,” says science journalist Ben Goldfarb, author of the 2023 book Crossings: How Road Ecology Is Shaping the Future of Our Planet. Goldfarb wrote about this problem for the March 2024 issue of Smithsonian. For Earth Day, we’ll talk to him about what’s being done to make the relationship between roads and lands more harmonious, and we’ll meet Fraser Shilling—a scientist at the University of California, Davis, who’ll tell us what he’s learned from his rigorous scholarly examination of … roadkill. A transcript is below. To subscribe to “There’s More to That,” and to listen to past episodes on the devastating effects of wildfires, a NASA mission to capture asteroid dust and the 2024 North American total solar eclipse, find us on Apple Podcasts, Spotify or wherever you get your podcasts. Chris Klimek: Fraser Shilling was out driving in California one day when he saw something unusual in the road. Fraser Shilling: There was this brown, fluffy thing, and I thought, “What is that? It’s such a strange-looking animal.” Klimek: Most people don’t have a habit of stopping to check out roadkill when they see it on the highway, but this is Fraser’s job. He actually studies roadkill. More specifically, he’s the director of the Road Ecology Center at the University of California, Davis. Shilling: I’ve done some sketchy pullovers on interstates, because if it’s a porcupine, if it’s a bear, I really want to make sure that’s what it is. Klimek: Road ecology is the study of how roads and highways impact local ecosystems. So, to Fraser, a dead animal in the road is important scientific evidence. Shilling: I think it’s a really important activity, obviously, and I have to do my part. I can’t just expect other people to collect the data. Klimek: But on this day in particular, it was a false alarm. Shilling: And I pulled over, and it was a teddy bear. Klimek: From Smithsonian magazine and PRX Productions, this is “There’s More to That,” the show that may definitively solve, right here in this episode, why a chicken would want to cross a road. This week, just in time for Earth Day and spring migration season, we’ll learn all about road ecology, what our roads are doing to our ecosystems and how we can fix it. I’m Chris Klimek.Klimek: One dead squirrel or dead deer in a road might not be that much cause for concern, but if you keep finding dead deer in the same stretch of road, then there’s obviously a problem, both for the deer and for the people that use that road. Shilling: This has happened to me. I’ve driven around a curve, you don’t have time to stop if you see something around that curve, and I had, in one stretch of Highway 12 in California, three male deer within a mile of each other. They’re just standing in or about to enter the road. Very alarming. I don’t think I would’ve died. I was probably only going 50, but it definitely would’ve been a noticeable impact on my life. But most of the animals are not a safety concern. Most of the animals that are being hit are smaller, like newts. There are places where newts are migrating across roads between where they spend their adult phase and where they’re going to reproduce. They’re just annihilated by traffic. And some areas, you think, “Well, they’ve always been doing that, so what’s the big deal?” But where it becomes a big deal is that you get fewer and fewer and fewer newts over time. Part of that is just loss from the regular traffic that’s occurring, but also, as you increase traffic, you’re increasing the number of newts that are getting killed, and, eventually, you’re going to wipe out the population. These are real-time ecological disasters, some of them. Klimek: Do people generally get it, or does it take a bit of explaining for you to say like, “No, this is actually valuable data that we can collect and learn from?” Shilling: Well, at the beginning, as you might imagine, there were people trying to be funny, ways of asking questions. I had a SiriusXM station interview, probably the weirdest media discussion about roadkill that I’ve had. But it was interesting. You’ve got these shock jocks, initially they were making fun of it, but then they started to get into it.Ben Goldfarb: There are just so many different ways in which our transportation infrastructure disrupts animal lives. Klimek: Ben Goldfarb is the author of an acclaimed book called Crossings: How Road Ecology Is Shaping the Future of Our Planet. Goldfarb: The dead deer or raccoon or squirrel we’ve all seen by the side of the road, that’s just the tip of the iceberg. Roads are this incredibly disruptive force all over the planet that are truly changing wild animals’ lives and our own lives in almost unfathomable, unaccountable ways. Generally, roads are enormous sources of pollution, right? Our cars are constantly bleeding cadmium and copper and zinc and microplastics. One of the big issues that scientists have only recently discovered is that tire particles are a huge problem. I think there’s something like 6 million tons of tire particles that enter the environment every year, and they contain this chemical called 6PPD, which kills salmon in huge numbers. Another big issue is invasive species. In Oregon, there’s a fungus that actually rides in truck tire treads and gets dispersed up the road network that way and kills trees. There’s all kinds of novel agents, both chemical and biological, that are using these roads to spread through our forests. Klimek: These particularly toxic roads, are they concentrated in a few geographic areas, or are they dispersed all over? Goldfarb: I think it’s a pretty widespread problem, but road salt, which is in some ways probably the most transformative, consequential pollutant along our road networks, and obviously that’s something that we use as a de-icing chemical. So that’s really a Northern issue. I think Minnesota is the most profligate user of de-icing salt, and that’s turning all of these freshwater rivers and lakes and streams into functionally brackish estuaries. There are some cases where ocean crabs have entered these freshwater ecosystems, because that’s just how salty they’ve gotten. And then, another big issue, too, is that: Look, animals like salt. If you’ve got these salty roadsides and you’re luring all of these deer and moose and other critters to the roadside, well that’s also a huge roadkill issue. Klimek: Are there other de-icing agents available that don’t have such severe consequences for the environment? Goldfarb: Beet juice has been used in some places. It doesn’t smell great, so it hasn’t really caught on, and it’s also a little bit eerie to see bright red bloody-looking roads that are covered in beet juice. So the quest for a universally beloved, non-salt de-icer continues. Klimek: Yeah. On the beet juice note, I do use a citrus-based chain degreaser on my bicycle. It’s ground up orange peels or something that they claim is eco-friendly and as effective as any artificial chemical. So I hope that’s right. Goldfarb: Well, the fact that you’re getting around via bicycle, that’s a big win right there. So, Chris, you’re doing pretty good, man. Klimek: Is there any way in which our roads are a good thing for animals? Goldfarb: It depends who you are, right? The scavengers, for example, the turkey vultures or the coyotes that use roadkill as this resource, essentially. Or think about the Midwest, we’ve turned all of the landscape into corn and soy monoculture, and some of the only strips of native prairie vegetation remaining are those roadsides and road medians that end up being pretty good habitat for animals like monarch butterflies. Roads are ultimately ecosystems in their own right, and every ecosystem has winners and losers. Klimek: Yeah. You opened the door to this a little bit when you mentioned de-icing salt, but how do roads alter biodiversity more broadly than just animals being struck by cars? Goldfarb: I think a lot about that barrier effect. These walls of traffic that animals don’t even attempt to cross in many places. Lots of big interstate highways actually have very little roadkill, because animals never even try to cross the highway. And yet, they’re having enormous impacts on wildlife distribution. You end up, in some cases, with very inbred populations. Famously, in Southern California, there’s this cluster of mountain lions living near Los Angeles surrounded by freeways. And those animals have ended up having to mate with their own daughters and granddaughters and even great-granddaughters because they just can’t cross the highway to escape this little island of habitat, and no new animals can cross to enter the population. So even without killing animals directly, these roads are dramatically changing their lives and influencing where they can live and who they can mate with. Klimek: So, conversely, how are humans impacted by animals in the roadway? Goldfarb: Roadkill is a really dangerous event for drivers as well as for animals. There are up to 2 million large animal crashes in this country every year, most of them with white-tailed deer, and several hundred drivers die in those incidents. And road collisions with animals are costing society more than $8 billion every year, in vehicle repairs and hospital bills and tow trucks and so on. This epidemic of wildlife-vehicle collisions is a human public health and safety crisis, in a lot of ways. Klimek: Are there other ways in which animals have adapted to this influx of road construction? Goldfarb: Certainly animals have ingenious strategies for living alongside all of this infrastructure. In Chicago, there’s this very famous population of urban coyotes that looks both ways and crosses at the crosswalks. They’re very intelligent animals. There are even cases of evolution that have occurred due to road construction. There’s a very famous example in Nebraska where cliff swallows, which are those birds who build their little mud nests on highway overpasses and bridges, they’ve actually evolved over time to have shorter wings. Because if you have a long wing as a bird, that’s good for flying long, straight directions, whereas having a short wing is good for maneuverability and making lots of tight rolls and turns to avoid an 18-wheeler. The long-wing swallows have gotten weeded from the population by roadkill, and the shorter-wing swallows remain, and now the whole population is becoming less susceptible to roadkill. That’s just incredible to think about, right? That evolution is usually this process that unfolds over the course of thousands or millions of years, but roads and cars are such a powerful selective pressure that they’re literally driving evolution in a matter of decades. Klimek: Have road construction techniques evolved over the decades? Are we building them in a more eco-conscious way now or not so much? Goldfarb: It is true that roads are one of the technologies that are least amenable to disruption. One thing we’ve become much more cognizant of, and better about, is the need to build wildlife crossings: overpasses and underpasses and tunnels that allow animals to safely cross highways. And, typically, whenever there’s a big highway modification or expansion, they’ll include some wildlife crossings. We’ve got the equipment out there already—let’s just put it in a tunnel or something like that to facilitate animal movements. Klimek: And from what we’ve seen, do animals use these crossings when we build them? Do they figure out that’s a safer way to get across the eight lanes or however many there are? Goldfarb: Absolutely. Yeah, crossings are extremely effective. Typically, they reduce vehicle collisions by 90 percent or so, in part because, typically, you’ve got a crossing and then you’ve got roadside fences that funnel the animals to the crossings and allow them to safely cross the highway. So there’s lots of research showing that animals definitely use these things. And in many cases, they actually pay for themselves. Sometimes the transportation department will propose a new $5 million wildlife overpass, and everybody shakes their head about the idea of spending $5 million on helping elk cross a highway. But actually, by preventing all of these really dangerous, expensive crashes with animals and vehicles, these crossings are actually recouping their own construction costs. And that’s a big part of the reason that so many transportation departments around the country are really embracing them. Klimek: What do these crossings look like? Are they similar to what a pedestrian bridge or tunnel would be? Goldfarb: In some ways, yeah. The basic technology isn’t all that different, but you want to make them look like habitat. You want an animal to feel comfortable crossing this novel, weird structure. So typically, the overpasses especially will have shrubs and even whole trees and dirt. And one of the cool things that’s happening now in road ecology is that we’re thinking about different species. It used to be that engineers and biologists were very focused on the big animals, the deer and the elk. And now we’re also thinking, “Well, wait a second, what does a meadow vole or a snake or a lizard need to feel comfortable on these crossings?” You tend to see lots of rock piles and log jams and other little micro-habitat features that might induce an animal to run across. Klimek: Yeah. I know you mentioned deer specifically as one of the major sources of roadkill and accidents. Are there other significant categories of animals that changed their patterns as a result of these crossings being made available? Goldfarb: There are incredibly successful crossings for grizzly bears and pronghorn antelope and salamanders. There have been crossings built for this incredible diversity of species, and they’re really effective. But it’s important to really think about what different species need. For example, the difference between black bears and grizzly bears. Grizzly bears were plains animals who lived out into the prairies. That was where Lewis and Clark saw them in eastern Montana. So they like to be out in the open. They like having a big, open bridge to walk across so they can confront their enemies with their power and speed. Whereas black bears are more forest dwellers and more comfortable in tighter spaces, potentially, and they’re typically happier using smaller underpasses that a grizzly bear would probably avoid. So different species just have different requirements for these crossing structures, and that’s one of the things that road ecologists do, is to think, “OK, in this given place where we want to build one of these crossings, what are the species we have to account for, and how do we account for them in the design of this structure?” Klimek: Salamanders is not one of the species I was picturing as I was reading the excerpt from your book Crossings. So tell us more about that. How do you get a salamander to cross where you want it to cross? Goldfarb: Amphibians, even though they’re small, they’re also migratory. They travel proportionately very large distances, and they’re typically moving between their upland forest habitat, going down to their breeding ponds, and they’re often moving in large numbers on these warm, wet spring nights. The problem is that we tend to build our roads in the same low-lying areas where water collects and amphibians breed. So in many cases, you get these big squishing events of salamanders and frogs and toads and other amphibians. Again, those warm, wet spring nights in the Northeast are just the most dangerous times. Yeah, the phrase “massive squishing event” is actually in a road ecology textbook. Klimek: Oh, wow. Goldfarb: There are a number of great salamander and frog tunnels, these little narrow passages that go under roadways. You could drive over them a thousand times and never know they were there, but they do tend to work really well. Klimek: The roads we drive on every day are only one of Ben’s concerns. Ben recently wrote an article for Smithsonian magazine about roads that have fallen out of use. He says that you can’t just leave an old, decaying road to sit and expect nature to reclaim it. Goldfarb: There’s just this huge road density out there. In some places, there are more roads per square mile in national forests than there are in New York City, which is pretty hard to fathom. And those roads, even though they’re out in the middle of nowhere, they still have a big environmental impact. What my story’s about, in a lot of ways is, OK, what do we do about those impacts? If roads cause problems in these otherwise wild areas, can we eliminate those roads? And that’s what the Forest Service and its many partner organizations are doing in many cases, is getting in there with the same heavy machinery that built the roads—in some cases, the big, yellow Tonka toys—and just tearing that roadbed up and allowing nature to reclaim it. Which is really exciting. Klimek: So generally, if one wants to decommission a road safely with minimal environmental impact, how could that be done? Goldfarb: One of the challenges is that often the soil is really compacted. You’ve got 30 years of big, heavy logging trucks rolling down these dirt roads, and so all of that pressure and weight over time has really compacted the soil. So it’s super-hard for any vegetation to really effectively take root there. What firms that do road decommissioning and the Forest Service does is rip up that roadbed to loosen up the soil, and then you can replant it, and that vegetation will have a much greater chance of success. It’s funny, I visited a lot of these sites where road decommissioning was in progress, and it looks like a war zone. The earth is just ripped up everywhere, and there are saplings lying over the road that they tear up and use to cover the roads so that seedlings and wildflowers and stuff can shelter in the vegetative cover. So the whole thing looks like a tornado went through or something like that. But you come back in 20 years, and it truly looks like a forest. I visited a bunch of sites in Idaho and Montana where roads were decommissioned 20 or 30 years ago, and you truly would have no idea that a road had ever been there, if there wasn’t a scientist telling you so. So it can be pretty inspiring. Klimek: What are the barriers to this always being done in the most conscientious way? Expense? Politics? A combination of factors? Why doesn’t this always happen the way we might wish? Goldfarb: You put your finger on the two big ones. Expense and politics. The expense, the U.S. Forest Service, this giant federal agency that manages something like 190 million acres of American public land, is also the largest road manager in the world, I think. Unbeknownst to most people, the Forest Service has something like 370,000 miles of road. You get to the moon and most of the way back on Forest Service roads. In general, you’re looking at $5,000 to $15,000 per mile of decommissioned road—that tends to add up quickly. The Forest Service is also chronically a funding-challenged agency. So much of its budget goes toward fighting wildfires, and there’s often very little left over for anything else, including road decommissioning. So expense is definitely a big one. And then there’s also, oftentimes the Forest Service proposes closing some roads, and there’s a lot of uproar from locals who don’t want to see those roads taken out of commission. So it can definitely be politically contentious at times. Klimek: To back up a few decades, how did the Forest Service become the keeper of these tens of thousands of miles of road? Goldfarb: Initially, a lot of those roads were built with really good intentions. The Forest Service was created in the early 1900s, and its first generation of rangers basically said, “We have been tasked with stewarding these forests, and we need roads to do that. We need to be able to fight fires and to remove trees that have been killed by beetles and keep an eye on the elk population. We need these roads to manage this land.” That was where a lot of those early roads came from, I would say. And then in the 1950s, after World War II, there was this huge economic boom, a lot of home construction going on. And a lot of the private timber lands in America had been clear-cut already, and those national forests were the site of all of this industrial logging. And suddenly those early roads, those Forest Service roads, became the basis for this vast new network of logging roads. And in many cases, it was these private timber companies that the Forest Service was effectively paying to build logging roads on public land. And so that’s where, when we talk about forests that have higher road densities than New York City, what we’re talking about are these incredibly dense networks of logging roads. One biologist told me that you go to some forests and it looks like the loggers must have driven to every single tree, because the roads are just so thick. And it’s actually very poignant to read the journals and memoirs of some of these early Forest Service rangers, as I did, because they talk about the pain of seeing these forests that they love just totally overrun with roads that they helped facilitate. Klimek: Here’s the good news: Ben says there’s a lot of cause for optimism right now. Goldfarb: Earlier we were talking about funding being one of the primary limitations for road decommissioning. And now, there’s just a lot more funding available, really thanks to these two giant pieces of legislation passed under the Biden administration, the Bipartisan Infrastructure Act and the Inflation Reduction Act. And both of those giant laws have different pots of money embedded within them that can be used for road decommissioning. In the Infrastructure Act, there’s this thing called the Legacy Roads and Trails Program, which is, basically, $250 million for road restoration and rehabilitation. And then, in the IRA, the Inflation Reduction Act, there’s also all of this money that can be used by the Bureau of Land Management, which is the Forest Service’s sister agency, for road restoration. So there are just these big new pots of money coming online now and being distributed. And everybody I talked to for this story was just really excited about the prospects for road removal in the years ahead. Klimek: That Smithsonian story you wrote was really focused on the removal of forest roads, rural roads, but what about the freeways and roads we were discussing earlier that remain heavily used? Are there ways of reducing the environmental harm that they cause? Goldfarb: Yeah, it’s a great question. I think that one of the exciting things in that bipartisan Infrastructure Act that also has money for road removal, is that it also has $350 million for those new wildlife crossings that we were talking about. Which is easily the largest pot of money for animal passages ever put together. Historically, it’s been the Western states that have built a lot of these animal passages, but now states like Pennsylvania and South Dakota and Nebraska are getting interested. I think that in the next five to ten years, thanks to this big federal grant program, we’re going to have lots more wildlife crossings popping up all over the country. And granted, that’s not going to solve the problem of roads in nature, obviously, but hopefully it’ll at least help to alleviate some of the really negative impacts. Klimek: Smithsonian magazine contributor Ben Goldfarb is the author of Crossings: How Road Ecology Is Shaping the Future of Our Planet. This has been a really illuminating conversation, Ben. Thank you. Goldfarb: Thank you so much, Chris. Yeah, I appreciate your time and interest. Klimek: To read Goldfarb’s latest article in Smithsonian about safely decommissioning roads, and to learn more about how to report roadkill sightings to Shilling’s database at UC Davis, check out the links in our show notes.Klimek: And speaking of Shilling, we couldn’t leave you without sharing one more story from him. We like to end all of our episodes with a “dinner party fact.” This is an anecdote or piece of information to stoke the conversation at your next social gathering. And for me, well, I can’t stop thinking about what Fraser told me about the culinary aspect of his roadkill research. Hold onto your dinners, folks. Shilling: It falls a little bit into that shock jock kind of category of, “Oh, roadkill is so weird. What is that? What are you talking about?” But there’s a huge population of people that do collect and eat animals fresh off the road. I’ve done that. I’ve stopped on the side of I-5, 101, 395, and I have sliced out parts of deer from a fresh carcass and taken them home. Klimek: Don’t knock it until you’ve tried it, I guess. Shilling: Steak in a grocery store or chicken, how many days ago was that thing alive? But I would bet anything that the meat I’m cutting out from inside a deer that was killed a day ago has way less bacteria on it than that steak in a supermarket. Klimek: After the New York Times published an article about his research in 2010, Fraser got an unexpected call. Shilling: A chef in San Francisco called me up and said, “Hey, I do these unique meals for wealthy people, and we want to do a really just incredible dinner made from roadkill. Can I use your system to find out where to get something?” And I thought about it and I said, “Yeah, actually,” because our reporting’s real-time. So I said, “Well, how about this?” I knew he was in San Francisco, “I’m going to look at our system, as soon as something comes in that looks like it was probably fresh, especially if there’s a photograph, I’m going to forward the location to you, and you can just zip out there and go get it.” And he did. He did exactly that, and did a meal of raccoon, which I was kind of surprised about. And rabbit, which makes more sense, based on that data collection. It was not at all legal, but definitely interesting. Klimek: “There’s More to That” is not legal advice, but it is a production of Smithsonian magazine and PRX Productions. From the magazine, our team is me, Debra Rosenberg and Brian Wolly. From PRX, our team is Jessica Miller, Genevieve Sponsler, Adriana Rozas Rivera, Ry Dorsey and Edwin Ochoa. The executive producer of PRX Productions is Jocelyn Gonzales. Our episode artwork is by Emily Lankiewicz. Fact-checking by Stephanie Abramson. Our music is from APM Music. I’m Chris Klimek. Thanks for listening. Get the latest Science stories in your inbox.

Our byways are an unnatural incursion into the natural world, especially when they’re allowed to fall into disuse. Meet a roadkill scientist and a journalist tracking how roads mess with nature—and what we can do about it

Smithmag-Podcast-S02-Ep05-Roads-article.jpg

As highways encroach ever further into animal habitats, drivers and wildlife are in greater danger than ever. And off the beaten path, decaying old forest roads are inflicting damage as well. “Roads are this incredibly disruptive force all over the planet that are truly changing wild animals’ lives and our own lives in almost unfathomable, unaccountable ways,” says science journalist Ben Goldfarb, author of the 2023 book Crossings: How Road Ecology Is Shaping the Future of Our Planet.

Goldfarb wrote about this problem for the March 2024 issue of Smithsonian. For Earth Day, we’ll talk to him about what’s being done to make the relationship between roads and lands more harmonious, and we’ll meet Fraser Shilling—a scientist at the University of California, Davis, who’ll tell us what he’s learned from his rigorous scholarly examination of … roadkill.

A transcript is below. To subscribe to “There’s More to That,” and to listen to past episodes on the devastating effects of wildfires, a NASA mission to capture asteroid dust and the 2024 North American total solar eclipse, find us on Apple Podcasts, Spotify or wherever you get your podcasts.


Chris Klimek: Fraser Shilling was out driving in California one day when he saw something unusual in the road.

Fraser Shilling: There was this brown, fluffy thing, and I thought, “What is that? It’s such a strange-looking animal.”

Klimek: Most people don’t have a habit of stopping to check out roadkill when they see it on the highway, but this is Fraser’s job. He actually studies roadkill. More specifically, he’s the director of the Road Ecology Center at the University of California, Davis.

Shilling: I’ve done some sketchy pullovers on interstates, because if it’s a porcupine, if it’s a bear, I really want to make sure that’s what it is.

Klimek: Road ecology is the study of how roads and highways impact local ecosystems. So, to Fraser, a dead animal in the road is important scientific evidence.

Shilling: I think it’s a really important activity, obviously, and I have to do my part. I can’t just expect other people to collect the data.

Klimek: But on this day in particular, it was a false alarm.

Shilling: And I pulled over, and it was a teddy bear.

Klimek: From Smithsonian magazine and PRX Productions, this is “There’s More to That,” the show that may definitively solve, right here in this episode, why a chicken would want to cross a road. This week, just in time for Earth Day and spring migration season, we’ll learn all about road ecology, what our roads are doing to our ecosystems and how we can fix it. I’m Chris Klimek.


Klimek: One dead squirrel or dead deer in a road might not be that much cause for concern, but if you keep finding dead deer in the same stretch of road, then there’s obviously a problem, both for the deer and for the people that use that road.

Shilling: This has happened to me. I’ve driven around a curve, you don’t have time to stop if you see something around that curve, and I had, in one stretch of Highway 12 in California, three male deer within a mile of each other. They’re just standing in or about to enter the road. Very alarming. I don’t think I would’ve died. I was probably only going 50, but it definitely would’ve been a noticeable impact on my life. But most of the animals are not a safety concern. Most of the animals that are being hit are smaller, like newts. There are places where newts are migrating across roads between where they spend their adult phase and where they’re going to reproduce. They’re just annihilated by traffic.

And some areas, you think, “Well, they’ve always been doing that, so what’s the big deal?” But where it becomes a big deal is that you get fewer and fewer and fewer newts over time. Part of that is just loss from the regular traffic that’s occurring, but also, as you increase traffic, you’re increasing the number of newts that are getting killed, and, eventually, you’re going to wipe out the population. These are real-time ecological disasters, some of them.

Klimek: Do people generally get it, or does it take a bit of explaining for you to say like, “No, this is actually valuable data that we can collect and learn from?”

Shilling: Well, at the beginning, as you might imagine, there were people trying to be funny, ways of asking questions. I had a SiriusXM station interview, probably the weirdest media discussion about roadkill that I’ve had. But it was interesting. You’ve got these shock jocks, initially they were making fun of it, but then they started to get into it.


Ben Goldfarb: There are just so many different ways in which our transportation infrastructure disrupts animal lives.

Klimek: Ben Goldfarb is the author of an acclaimed book called Crossings: How Road Ecology Is Shaping the Future of Our Planet.

Goldfarb: The dead deer or raccoon or squirrel we’ve all seen by the side of the road, that’s just the tip of the iceberg. Roads are this incredibly disruptive force all over the planet that are truly changing wild animals’ lives and our own lives in almost unfathomable, unaccountable ways.

Generally, roads are enormous sources of pollution, right? Our cars are constantly bleeding cadmium and copper and zinc and microplastics. One of the big issues that scientists have only recently discovered is that tire particles are a huge problem. I think there’s something like 6 million tons of tire particles that enter the environment every year, and they contain this chemical called 6PPD, which kills salmon in huge numbers.

Another big issue is invasive species. In Oregon, there’s a fungus that actually rides in truck tire treads and gets dispersed up the road network that way and kills trees. There’s all kinds of novel agents, both chemical and biological, that are using these roads to spread through our forests.

Klimek: These particularly toxic roads, are they concentrated in a few geographic areas, or are they dispersed all over?

Goldfarb: I think it’s a pretty widespread problem, but road salt, which is in some ways probably the most transformative, consequential pollutant along our road networks, and obviously that’s something that we use as a de-icing chemical. So that’s really a Northern issue. I think Minnesota is the most profligate user of de-icing salt, and that’s turning all of these freshwater rivers and lakes and streams into functionally brackish estuaries. There are some cases where ocean crabs have entered these freshwater ecosystems, because that’s just how salty they’ve gotten.

And then, another big issue, too, is that: Look, animals like salt. If you’ve got these salty roadsides and you’re luring all of these deer and moose and other critters to the roadside, well that’s also a huge roadkill issue.

Klimek: Are there other de-icing agents available that don’t have such severe consequences for the environment?

Goldfarb: Beet juice has been used in some places. It doesn’t smell great, so it hasn’t really caught on, and it’s also a little bit eerie to see bright red bloody-looking roads that are covered in beet juice. So the quest for a universally beloved, non-salt de-icer continues.

Klimek: Yeah. On the beet juice note, I do use a citrus-based chain degreaser on my bicycle. It’s ground up orange peels or something that they claim is eco-friendly and as effective as any artificial chemical. So I hope that’s right.

Goldfarb: Well, the fact that you’re getting around via bicycle, that’s a big win right there. So, Chris, you’re doing pretty good, man.

Klimek: Is there any way in which our roads are a good thing for animals?

Goldfarb: It depends who you are, right? The scavengers, for example, the turkey vultures or the coyotes that use roadkill as this resource, essentially. Or think about the Midwest, we’ve turned all of the landscape into corn and soy monoculture, and some of the only strips of native prairie vegetation remaining are those roadsides and road medians that end up being pretty good habitat for animals like monarch butterflies. Roads are ultimately ecosystems in their own right, and every ecosystem has winners and losers.

Klimek: Yeah. You opened the door to this a little bit when you mentioned de-icing salt, but how do roads alter biodiversity more broadly than just animals being struck by cars?

Goldfarb: I think a lot about that barrier effect. These walls of traffic that animals don’t even attempt to cross in many places. Lots of big interstate highways actually have very little roadkill, because animals never even try to cross the highway. And yet, they’re having enormous impacts on wildlife distribution. You end up, in some cases, with very inbred populations. Famously, in Southern California, there’s this cluster of mountain lions living near Los Angeles surrounded by freeways. And those animals have ended up having to mate with their own daughters and granddaughters and even great-granddaughters because they just can’t cross the highway to escape this little island of habitat, and no new animals can cross to enter the population.

So even without killing animals directly, these roads are dramatically changing their lives and influencing where they can live and who they can mate with.

Klimek: So, conversely, how are humans impacted by animals in the roadway?

Goldfarb: Roadkill is a really dangerous event for drivers as well as for animals. There are up to 2 million large animal crashes in this country every year, most of them with white-tailed deer, and several hundred drivers die in those incidents. And road collisions with animals are costing society more than $8 billion every year, in vehicle repairs and hospital bills and tow trucks and so on. This epidemic of wildlife-vehicle collisions is a human public health and safety crisis, in a lot of ways.

Klimek: Are there other ways in which animals have adapted to this influx of road construction?

Goldfarb: Certainly animals have ingenious strategies for living alongside all of this infrastructure. In Chicago, there’s this very famous population of urban coyotes that looks both ways and crosses at the crosswalks. They’re very intelligent animals.

There are even cases of evolution that have occurred due to road construction. There’s a very famous example in Nebraska where cliff swallows, which are those birds who build their little mud nests on highway overpasses and bridges, they’ve actually evolved over time to have shorter wings. Because if you have a long wing as a bird, that’s good for flying long, straight directions, whereas having a short wing is good for maneuverability and making lots of tight rolls and turns to avoid an 18-wheeler. The long-wing swallows have gotten weeded from the population by roadkill, and the shorter-wing swallows remain, and now the whole population is becoming less susceptible to roadkill.

That’s just incredible to think about, right? That evolution is usually this process that unfolds over the course of thousands or millions of years, but roads and cars are such a powerful selective pressure that they’re literally driving evolution in a matter of decades.

Klimek: Have road construction techniques evolved over the decades? Are we building them in a more eco-conscious way now or not so much?

Goldfarb: It is true that roads are one of the technologies that are least amenable to disruption. One thing we’ve become much more cognizant of, and better about, is the need to build wildlife crossings: overpasses and underpasses and tunnels that allow animals to safely cross highways. And, typically, whenever there’s a big highway modification or expansion, they’ll include some wildlife crossings. We’ve got the equipment out there already—let’s just put it in a tunnel or something like that to facilitate animal movements.

Klimek: And from what we’ve seen, do animals use these crossings when we build them? Do they figure out that’s a safer way to get across the eight lanes or however many there are?

Goldfarb: Absolutely. Yeah, crossings are extremely effective. Typically, they reduce vehicle collisions by 90 percent or so, in part because, typically, you’ve got a crossing and then you’ve got roadside fences that funnel the animals to the crossings and allow them to safely cross the highway. So there’s lots of research showing that animals definitely use these things.

And in many cases, they actually pay for themselves. Sometimes the transportation department will propose a new $5 million wildlife overpass, and everybody shakes their head about the idea of spending $5 million on helping elk cross a highway. But actually, by preventing all of these really dangerous, expensive crashes with animals and vehicles, these crossings are actually recouping their own construction costs. And that’s a big part of the reason that so many transportation departments around the country are really embracing them.

Klimek: What do these crossings look like? Are they similar to what a pedestrian bridge or tunnel would be?

Goldfarb: In some ways, yeah. The basic technology isn’t all that different, but you want to make them look like habitat. You want an animal to feel comfortable crossing this novel, weird structure. So typically, the overpasses especially will have shrubs and even whole trees and dirt.

And one of the cool things that’s happening now in road ecology is that we’re thinking about different species. It used to be that engineers and biologists were very focused on the big animals, the deer and the elk. And now we’re also thinking, “Well, wait a second, what does a meadow vole or a snake or a lizard need to feel comfortable on these crossings?” You tend to see lots of rock piles and log jams and other little micro-habitat features that might induce an animal to run across.

Klimek: Yeah. I know you mentioned deer specifically as one of the major sources of roadkill and accidents. Are there other significant categories of animals that changed their patterns as a result of these crossings being made available?

Goldfarb: There are incredibly successful crossings for grizzly bears and pronghorn antelope and salamanders. There have been crossings built for this incredible diversity of species, and they’re really effective. But it’s important to really think about what different species need.

For example, the difference between black bears and grizzly bears. Grizzly bears were plains animals who lived out into the prairies. That was where Lewis and Clark saw them in eastern Montana. So they like to be out in the open. They like having a big, open bridge to walk across so they can confront their enemies with their power and speed. Whereas black bears are more forest dwellers and more comfortable in tighter spaces, potentially, and they’re typically happier using smaller underpasses that a grizzly bear would probably avoid.

So different species just have different requirements for these crossing structures, and that’s one of the things that road ecologists do, is to think, “OK, in this given place where we want to build one of these crossings, what are the species we have to account for, and how do we account for them in the design of this structure?”

Klimek: Salamanders is not one of the species I was picturing as I was reading the excerpt from your book Crossings. So tell us more about that. How do you get a salamander to cross where you want it to cross?

Goldfarb: Amphibians, even though they’re small, they’re also migratory. They travel proportionately very large distances, and they’re typically moving between their upland forest habitat, going down to their breeding ponds, and they’re often moving in large numbers on these warm, wet spring nights. The problem is that we tend to build our roads in the same low-lying areas where water collects and amphibians breed. So in many cases, you get these big squishing events of salamanders and frogs and toads and other amphibians. Again, those warm, wet spring nights in the Northeast are just the most dangerous times. Yeah, the phrase “massive squishing event” is actually in a road ecology textbook.

Klimek: Oh, wow.

Goldfarb: There are a number of great salamander and frog tunnels, these little narrow passages that go under roadways. You could drive over them a thousand times and never know they were there, but they do tend to work really well.

Klimek: The roads we drive on every day are only one of Ben’s concerns. Ben recently wrote an article for Smithsonian magazine about roads that have fallen out of use. He says that you can’t just leave an old, decaying road to sit and expect nature to reclaim it.

Goldfarb: There’s just this huge road density out there. In some places, there are more roads per square mile in national forests than there are in New York City, which is pretty hard to fathom. And those roads, even though they’re out in the middle of nowhere, they still have a big environmental impact.

What my story’s about, in a lot of ways is, OK, what do we do about those impacts? If roads cause problems in these otherwise wild areas, can we eliminate those roads? And that’s what the Forest Service and its many partner organizations are doing in many cases, is getting in there with the same heavy machinery that built the roads—in some cases, the big, yellow Tonka toys—and just tearing that roadbed up and allowing nature to reclaim it. Which is really exciting.

Klimek: So generally, if one wants to decommission a road safely with minimal environmental impact, how could that be done?

Goldfarb: One of the challenges is that often the soil is really compacted. You’ve got 30 years of big, heavy logging trucks rolling down these dirt roads, and so all of that pressure and weight over time has really compacted the soil. So it’s super-hard for any vegetation to really effectively take root there. What firms that do road decommissioning and the Forest Service does is rip up that roadbed to loosen up the soil, and then you can replant it, and that vegetation will have a much greater chance of success.

It’s funny, I visited a lot of these sites where road decommissioning was in progress, and it looks like a war zone. The earth is just ripped up everywhere, and there are saplings lying over the road that they tear up and use to cover the roads so that seedlings and wildflowers and stuff can shelter in the vegetative cover. So the whole thing looks like a tornado went through or something like that.

But you come back in 20 years, and it truly looks like a forest. I visited a bunch of sites in Idaho and Montana where roads were decommissioned 20 or 30 years ago, and you truly would have no idea that a road had ever been there, if there wasn’t a scientist telling you so. So it can be pretty inspiring.

Klimek: What are the barriers to this always being done in the most conscientious way? Expense? Politics? A combination of factors? Why doesn’t this always happen the way we might wish?

Goldfarb: You put your finger on the two big ones. Expense and politics. The expense, the U.S. Forest Service, this giant federal agency that manages something like 190 million acres of American public land, is also the largest road manager in the world, I think. Unbeknownst to most people, the Forest Service has something like 370,000 miles of road. You get to the moon and most of the way back on Forest Service roads.

In general, you’re looking at $5,000 to $15,000 per mile of decommissioned road—that tends to add up quickly. The Forest Service is also chronically a funding-challenged agency. So much of its budget goes toward fighting wildfires, and there’s often very little left over for anything else, including road decommissioning. So expense is definitely a big one.

And then there’s also, oftentimes the Forest Service proposes closing some roads, and there’s a lot of uproar from locals who don’t want to see those roads taken out of commission. So it can definitely be politically contentious at times.

Klimek: To back up a few decades, how did the Forest Service become the keeper of these tens of thousands of miles of road?

Goldfarb: Initially, a lot of those roads were built with really good intentions. The Forest Service was created in the early 1900s, and its first generation of rangers basically said, “We have been tasked with stewarding these forests, and we need roads to do that. We need to be able to fight fires and to remove trees that have been killed by beetles and keep an eye on the elk population. We need these roads to manage this land.” That was where a lot of those early roads came from, I would say.

And then in the 1950s, after World War II, there was this huge economic boom, a lot of home construction going on. And a lot of the private timber lands in America had been clear-cut already, and those national forests were the site of all of this industrial logging. And suddenly those early roads, those Forest Service roads, became the basis for this vast new network of logging roads. And in many cases, it was these private timber companies that the Forest Service was effectively paying to build logging roads on public land.

And so that’s where, when we talk about forests that have higher road densities than New York City, what we’re talking about are these incredibly dense networks of logging roads. One biologist told me that you go to some forests and it looks like the loggers must have driven to every single tree, because the roads are just so thick. And it’s actually very poignant to read the journals and memoirs of some of these early Forest Service rangers, as I did, because they talk about the pain of seeing these forests that they love just totally overrun with roads that they helped facilitate.

Klimek: Here’s the good news: Ben says there’s a lot of cause for optimism right now.

Goldfarb: Earlier we were talking about funding being one of the primary limitations for road decommissioning. And now, there’s just a lot more funding available, really thanks to these two giant pieces of legislation passed under the Biden administration, the Bipartisan Infrastructure Act and the Inflation Reduction Act. And both of those giant laws have different pots of money embedded within them that can be used for road decommissioning.

In the Infrastructure Act, there’s this thing called the Legacy Roads and Trails Program, which is, basically, $250 million for road restoration and rehabilitation. And then, in the IRA, the Inflation Reduction Act, there’s also all of this money that can be used by the Bureau of Land Management, which is the Forest Service’s sister agency, for road restoration. So there are just these big new pots of money coming online now and being distributed. And everybody I talked to for this story was just really excited about the prospects for road removal in the years ahead.

Klimek: That Smithsonian story you wrote was really focused on the removal of forest roads, rural roads, but what about the freeways and roads we were discussing earlier that remain heavily used? Are there ways of reducing the environmental harm that they cause?

Goldfarb: Yeah, it’s a great question. I think that one of the exciting things in that bipartisan Infrastructure Act that also has money for road removal, is that it also has $350 million for those new wildlife crossings that we were talking about. Which is easily the largest pot of money for animal passages ever put together. Historically, it’s been the Western states that have built a lot of these animal passages, but now states like Pennsylvania and South Dakota and Nebraska are getting interested.

I think that in the next five to ten years, thanks to this big federal grant program, we’re going to have lots more wildlife crossings popping up all over the country. And granted, that’s not going to solve the problem of roads in nature, obviously, but hopefully it’ll at least help to alleviate some of the really negative impacts.

Klimek: Smithsonian magazine contributor Ben Goldfarb is the author of Crossings: How Road Ecology Is Shaping the Future of Our Planet. This has been a really illuminating conversation, Ben. Thank you.

Goldfarb: Thank you so much, Chris. Yeah, I appreciate your time and interest.

Klimek: To read Goldfarb’s latest article in Smithsonian about safely decommissioning roads, and to learn more about how to report roadkill sightings to Shilling’s database at UC Davis, check out the links in our show notes.


Klimek: And speaking of Shilling, we couldn’t leave you without sharing one more story from him. We like to end all of our episodes with a “dinner party fact.” This is an anecdote or piece of information to stoke the conversation at your next social gathering. And for me, well, I can’t stop thinking about what Fraser told me about the culinary aspect of his roadkill research. Hold onto your dinners, folks.

Shilling: It falls a little bit into that shock jock kind of category of, “Oh, roadkill is so weird. What is that? What are you talking about?” But there’s a huge population of people that do collect and eat animals fresh off the road. I’ve done that. I’ve stopped on the side of I-5, 101, 395, and I have sliced out parts of deer from a fresh carcass and taken them home.

Klimek: Don’t knock it until you’ve tried it, I guess.

Shilling: Steak in a grocery store or chicken, how many days ago was that thing alive? But I would bet anything that the meat I’m cutting out from inside a deer that was killed a day ago has way less bacteria on it than that steak in a supermarket.

Klimek: After the New York Times published an article about his research in 2010, Fraser got an unexpected call.

Shilling: A chef in San Francisco called me up and said, “Hey, I do these unique meals for wealthy people, and we want to do a really just incredible dinner made from roadkill. Can I use your system to find out where to get something?” And I thought about it and I said, “Yeah, actually,” because our reporting’s real-time. So I said, “Well, how about this?” I knew he was in San Francisco, “I’m going to look at our system, as soon as something comes in that looks like it was probably fresh, especially if there’s a photograph, I’m going to forward the location to you, and you can just zip out there and go get it.”

And he did. He did exactly that, and did a meal of raccoon, which I was kind of surprised about. And rabbit, which makes more sense, based on that data collection. It was not at all legal, but definitely interesting.

Klimek: “There’s More to That” is not legal advice, but it is a production of Smithsonian magazine and PRX Productions. From the magazine, our team is me, Debra Rosenberg and Brian Wolly. From PRX, our team is Jessica Miller, Genevieve Sponsler, Adriana Rozas Rivera, Ry Dorsey and Edwin Ochoa. The executive producer of PRX Productions is Jocelyn Gonzales. Our episode artwork is by Emily Lankiewicz. Fact-checking by Stephanie Abramson. Our music is from APM Music.

I’m Chris Klimek. Thanks for listening.

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Most Life on Earth Is Dormant Right Now

Cells can go from wide awake to fast asleep in an instant.

This article was originally published by Quanta Magazine.Researchers recently reported the discovery of a natural protein, named Balon, that can bring a cell’s production of new proteins to a screeching halt. Balon was found in bacteria that hibernate in Arctic permafrost, but it also seems to be made by many other organisms and may be an overlooked mechanism for dormancy throughout the tree of life.For most life forms, the ability to shut oneself off is essential to staying alive. Harsh conditions such as lack of food or cold weather can appear out of nowhere. In these dire straits, rather than keel over and die, many organisms have mastered the art of dormancy. They slow down their activity and metabolism. Then, when better times return, they reanimate.Sitting around in a dormant state is actually the norm for the majority of life on Earth: By some estimates, 60 percent of all microbial cells are hibernating at any given time. Even in organisms whose entire bodies do not go dormant, such as most mammals, some cellular populations within them rest and wait for the best time to activate.“We live on a dormant planet,” says Sergey Melnikov, an evolutionary molecular biologist at Newcastle University, in the United Kingdom. “Life is mainly about being asleep.”But how do cells pull off this feat? Over the years, researchers have discovered a number of “hibernation factors,” proteins that cells use to induce and maintain a dormant state. When a cell detects some kind of adverse condition, such as starvation or cold, it produces a suite of hibernation factors to shut down its metabolism.Some hibernation factors dismantle cellular machinery; others prevent genes from being expressed. The most important ones, however, shut down the ribosome—the cell’s machine for building new proteins. Making proteins accounts for more than 50 percent of energy use in a growing bacterial cell. These hibernation factors throw sand in the gears of the ribosome, preventing it from synthesizing new proteins and thereby saving energy for the needs of basic survival.The discovery of Balon earlier this year, reported in Nature, presented a new hibernation factor. The protein is shockingly common: A search for its gene sequence uncovered its presence in 20 percent of all cataloged bacterial genomes. And it works in a way that molecular biologists had never seen before.Previously, all known ribosome-disrupting hibernation factors worked passively: They waited for a ribosome to finish building a protein and then prevented it from starting a new one. Balon, however, pulls the emergency brake. It stuffs itself into every ribosome in the cell, even interrupting active ribosomes in the middle of their work. Before Balon, hibernation factors had been seen only in empty ribosomes.“The Balon paper is amazingly detailed,” says the evolutionary biologist Jay Lennon, who studies microbial dormancy at Indiana University at Bloomington and was not involved in the new study. “It will add to our view of how dormancy works.”Melnikov and his graduate student Karla Helena-Bueno discovered Balon in Psychrobacter urativorans, a cold-adapted bacterium native to frozen soils and harvested from Arctic permafrost. (According to Melnikov, the bacterium was first found infecting a pack of frozen sausages in the 1970s and was then rediscovered by the famed genomicist Craig Venter on a trip to the Arctic.) They study P. urativorans and other unusual microbes to characterize the diversity of protein-building tools used across the spectrum of life and to understand how ribosomes can adapt to extreme environments.Because dormancy can be triggered by a variety of conditions, including starvation and drought, the scientists pursue this research with a practical goal in mind: “We can probably use this knowledge in order to engineer organisms that can tolerate warmer climates,” Melnikov says, “and therefore withstand climate change.”[Read: The best real estate to get animals through climate change]Helena-Bueno discovered Balon entirely by accident. She was trying to coax P. urativorans to grow happily in the lab. Instead she did the opposite. She left the culture in an ice bucket for too long and managed to cold-shock it. By the time she remembered it was there, the cold-adapted bacteria had gone dormant.Not wanting to waste the culture, the researchers pursued their original interests anyway. Helena-Bueno extracted the cold-shocked bacteria’s ribosomes and subjected them to cryo-EM. Short for “cryogenic electron microscopy,” cryo-EM is a technique for visualizing minuscule biological structures at high resolution. Helena-Bueno saw a protein jammed into the stalled ribosome’s “A site”—the “door” where amino acids are delivered for the construction of new proteins.Helena-Bueno and Melnikov didn’t recognize the protein. Indeed, it had never been described before. It bore a similarity to another bacterial protein, one that’s important for disassembling and recycling ribosomal parts, called Pelota from the Spanish for “ball.” So they named the new protein Balon, a different Spanish word for “ball.”Balon’s ability to halt the ribosome’s activity in its tracks is a crucial adaptation for a microbe under stress, says Mee-Ngan Frances Yap, a microbiologist at Northwestern University who wasn’t involved in the work. “When bacteria are actively growing, they produce lots of ribosomes and RNA,” she says. “When they encounter stress, a species might need to shut down translation” of RNA into new proteins to begin conserving energy for a potentially long hibernation period.Notably, Balon’s mechanism is a reversible process. Unlike other hibernation factors, it can be inserted to stall growth and then quickly ejected, like a cassette tape. It enables a cell to rapidly go dormant in an emergency and resuscitate itself just as rapidly to readapt to more favorable conditions.Balon can do this because it latches on to ribosomes in a unique way. Every ribosomal hibernation factor previously discovered physically blocks the ribosome’s A site, so any protein-making process that’s in progress must be completed before the factor can attach to turn off the ribosome. Balon, by contrast, binds near but not across the channel, which allows it to come and go regardless of what the ribosome is doing.Despite Balon’s mechanistic novelty, it’s an exceedingly common protein. Once it was identified, Helena-Bueno and Melnikov found genetic relatives of Balon in upward of 20 percent of all the bacterial genomes cataloged in public databases. With help from Mariia Rybak, a molecular biologist at the University of Texas Medical Branch, they characterized two of these alternative bacterial proteins: one from the human pathogen Mycobacterium tuberculosis, which causes tuberculosis, and another in Thermus thermophilus, which lives in the last place you’d ever catch P. urativorans—in ultra-hot underwater thermal vents. Both proteins also bind to the ribosome’s A site, suggesting that at least some of these genetic relatives act similarly to Balon in other bacterial species.Balon is notably absent from Escherichia coli and Staphylococcus aureus, the two most commonly studied bacteria and the most widely used models for cellular dormancy. By focusing on just a few lab organisms, scientists had missed a widespread hibernation tactic, Helena-Bueno says. “I tried to look into an under-studied corner of nature and happened to find something.”Every cell needs the ability to go dormant and wait for its moment. The laboratory model bacterium E. coli has five separate modes of hibernating, Melnikov says, each of which on its own is sufficient to enable the microbe to survive a crisis.“Most microbes are starving,” says Ashley Shade, a microbiologist at the University of Lyon, in France, who was not involved in the new study. “They’re existing in a state of want. They’re not doubling. They’re not living their best life.”But dormancy is also necessary outside periods of starvation. Even in organisms whose entire bodies do not go completely dormant, such as most mammals, individual cellular populations must wait for the best time to activate. Human oocytes lie dormant for decades waiting to be fertilized. Human stem cells are born into the bone marrow and then go quiescent, waiting for the body to call out to them to grow and differentiate. Fibroblasts in nervous tissue, lymphocytes of the immune system, and hepatocytes in the liver all enter dormant, inactive, nondividing phases and reactivate later.“This is not something that’s unique to bacteria or archaea,” Lennon says. “Every organism in the tree of life has a way of achieving this strategy. They can pause their metabolism.”Bears hibernate. Herpes viruses lysogenize. Worms develop into a dauer stage. Insects enter diapause. Amphibians aestivate. Birds go into torpor. All of these are words for the exact same thing: a dormant state that organisms can reverse when conditions are favorable.“Before the invention of hibernation, the only way to live was to keep growing without interruptions,” Melnikov says. “Putting life on pause is a luxury.”[Read: Hibernation is the extreme lifestyle that can stop aging]It’s also a type of population-level insurance. Some cells pursue dormancy by detecting environmental changes and responding accordingly. However, many bacteria use a stochastic strategy. “In randomly fluctuating environments, if you don’t go into dormancy sometimes, there’s a chance that the whole population will go extinct” through random encounters with disaster, Lennon says. In even the healthiest, happiest, fastest-growing cultures of E. coli, 5 to 10 percent of the cells will nevertheless be dormant. They are the designated survivors who will live should something happen to their more active, vulnerable cousins.In that sense, dormancy is a survival strategy for global catastrophes. That’s why Helena-Bueno studies hibernation. She’s interested in which species might remain stable despite climate change, which ones might be able to recover, and which cellular processes—like Balon-assisted hibernation—might help.More fundamentally, Melnikov and Helena-Bueno hope that the discovery of Balon and its ubiquity will help people reframe what is important in life. We all frequently go dormant, and many of us quite enjoy it. “We spend one-third of our life asleep, but we don’t talk about it at all,” Melnikov says. Instead of complaining about what we’re missing when we’re asleep, maybe we can experience it as a process that connects us to all life on Earth, including microbes slumbering deep in the Arctic permafrost.

Invisible Invaders: How Microplastics Sneak Into Your Brain

University of New Mexico researchers have identified that microplastics, once ingested, can migrate from the gut to organs such as the liver, kidneys, and brain,...

Researchers have discovered that microplastics, once ingested, travel from the gut to tissues such as the liver, kidneys, and brain, potentially causing significant health issues. The team’s findings emphasize the critical link between gut health and overall well-being, with ongoing studies exploring how diet and gut microbiota interact with microplastic absorption. Credit: SciTechDaily.comUniversity of New Mexico researchers have identified that microplastics, once ingested, can migrate from the gut to organs such as the liver, kidneys, and brain, potentially causing significant health issues.It’s happening every day. From our water, our food, and even the air we breathe, tiny plastic particles are finding their way into many parts of our body.But what happens once those particles are inside? What do they do to our digestive system? Significant Impact on Human HealthIn a recent paper published in the journal Environmental Health Perspectives, University of New Mexico researchers found that those tiny particles – microplastics – are having a significant impact on our digestive pathways, making their way from the gut and into the tissues of the kidney, liver, and brain.Research continues to show the importance of gut health. If you don’t have a healthy gut, it affects the brain, it affects the liver and so many other tissues. So even imagining that the microplastics are doing something in the in the gut, that chronic exposure could lead to systemic effects.— Eliseo Castillo, PhD, UNM School of MedicinePervasive Presence and Research FocusEliseo Castillo, PhD, an associate professor in the Division of Gastroenterology & Hepatology in the UNM School of Medicine’s Department of Internal Medicine and an expert in mucosal immunology, is leading the charge at UNM on microplastic research.“Over the past few decades, microplastics have been found in the ocean, in animals and plants, in tap water and bottled water,” Castillo, says. “They appear to be everywhere.”Ingestion and Internal EffectsScientists estimate that people ingest 5 grams of microplastic particles each week on average – equivalent to the weight of a credit card.While other researchers are helping to identify and quantify ingested microplastics, Castillo and his team focus on what the microplastics are doing inside the body, specifically to the gastrointestinal (GI) tract and to the gut immune system.Experimental Studies and FindingsOver a four-week period, Castillo, postdoctoral fellow Marcus Garcia, PharmD, and other UNM researchers exposed mice to microplastics in their drinking water. The amount was equivalent to the quantity of microplastics humans are believed to ingest each week.Microplastics had migrated out of the gut into the tissues of the liver, kidney and even the brain, the team found. The study also showed the microplastics changed metabolic pathways in the affected tissues.Concerns and Future Research“We could detect microplastics in certain tissues after the exposure,” Castillo says. “That tells us it can cross the intestinal barrier and infiltrate into other tissues.”Castillo says he’s also concerned about the accumulation of the plastic particles in the human body. “These mice were exposed for four weeks,” he says. “Now, think about how that equates to humans, if we’re exposed from birth to old age.”Impacts on Immune System and Chronic ConditionsThe healthy laboratory animals used in this study showed changes after brief microplastic exposure, Castillo says. “Now imagine if someone has an underlying condition, and these changes occur, could microplastic exposure exacerbate an underlying condition?”He has previously found that microplastics are also impacting macrophages – the immune cells that work to protect the body from foreign particles.Ongoing Investigations and Potential DiscoveriesIn a paper published in the journal Cell Biology & Toxicology in 2021, Castillo and other UNM researchers found that when macrophages encountered and ingested microplastics, their function was altered and they released inflammatory molecules.“It is changing the metabolism of the cells, which can alter inflammatory responses,” Castillo says. “During intestinal inflammation – states of chronic illness such as ulcerative colitis and Crohn’s disease, which are both forms of inflammatory bowel disease – these macrophages become more inflammatory and they’re more abundant in the gut.”Diet’s Role in Microplastic UptakeThe next phase of Castillo’s research, which is being led by postdoctoral fellow Sumira Phatak, PhD, will explore how diet is involved in microplastic uptake.“Everyone’s diet is different,” he says. “So, what we’re going to do is give these laboratory animals a high-cholesterol/high-fat diet, or high-fiber diet, and they will be either exposed or not exposed to microplastics. The goal is to try to understand if diet affects the uptake of microplastics into our body.”Castillo says one of his PhD students, Aaron Romero, is also working to understand why there is a change in the gut microbiota. “Multiple groups have shown microplastics change the microbiota, but how it changes the microbiota hasn’t been addressed.”Castillo hopes that his research will help uncover the potential impacts microplastics are having to human health and that it will help spur changes to how society produces and filtrates plastics.Future Directions and Societal Impact“At the end of the day, the research we are trying to do aims to find out how this is impacting gut health,” he says. “Research continues to show the importance of gut health. If you don’t have a healthy gut, it affects the brain, it affects the liver and so many other tissues. So even imagining that the microplastics are doing something in the in the gut, that chronic exposure could lead to systemic effects.”In Vivo Tissue Distribution of Polystyrene or Mixed Polymer Microspheres and Metabolomic Analysis after Oral Exposure in Mice” by Marcus M. Garcia, Aaron S. Romero, Seth D. Merkley, Jewel L. Meyer-Hagen, Charles Forbes, Eliane El Hayek, David P. Sciezka, Rachel Templeton, Jorge Gonzalez-Estrella, Yan Jin, Haiwei Gu, Angelica Benavidez, Russell P. Hunter, Selita Lucas, Guy Herbert, Kyle Joohyung Kim, Julia Yue Cui, Rama R. Gullapalli, Julie G. In, Matthew J. Campen, and Eliseo F. Castillo, 10 April 2024, Environmental Health Perspectives.DOI: 10.1289/EHP13435

Makah tribe gets federal approval to hunt up to 25 gray whales

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It has been 25 years since the Makah tribe last harpooned a gray whale, a practice its members consider a sacred tradition but was restricted by federal regulation. But on Thursday, the tribe was granted a long-sought waiver that allows them to hunt up to 25 whales in the next decade.The waiver from the National Oceanic and Atmospheric Administration is a major victory for the northwest Washington tribe. Whaling is central to Makah culture and treaty rights explicitly protect the tribe’s right to hunt whales, leaders said.“There is now a defined path for us to exercise our reserved treaty right,” Timothy Greene, chairman of the Makah Tribal Council told The Washington Post. “Our community has always been dependent on the ocean. It’s not for sport. The hunt is to provide for our people.”The decades-long wait was painful for the Makah, a community of about 1,500, he added, and it took far too long.Whale hunting is a thousands-years-old practice in Makah culture. It’s depicted in songs, dances and basketry, and intertwined with rituals and ceremonies. The tribe says it uses nearly every part of the whales it hunts, including the meat, blubber, bone and sinew.“It provided us a means to meet our nutritional needs, and provided for the exchange of goods throughout the region,” Greene said. “Our community and societal structure is better off for it.”Animal rights advocates, who have for years opposed the Makah’s pursuit of whaling, said they’re disappointed with Thursday’s decision. However limited, any whaling jeopardizes gray whale populations, and places the endangered Western North Pacific gray whales at risk of being harpooned, according to the Animal Welfare Institute.After a sharp decline in gray whales, the tribe voluntarily halted whaling in the 1920s. The United States later restricted whaling in the 1970s as many species hit the brink of extinction. After the Eastern North Pacific gray whale population recovered, and was no longer considered an endangered species, the Makah notified the federal government of its interest in resuming whaling. The 1999 hunt was the first since the 1920s. By 2000, a federal appeals court said that regulators failed to take a “hard look” at the hunt’s environmental impacts and ordered a halt.Twenty-one years later, an administrative law judge argued the tribe should be granted a waiver under the Marine Mammal Protection Act, a 1972 law that prohibits the killing of whales and other sea life.“Today is a monumental day in the efforts to allow the Makah tribe to exercise their treaty right to subsistence and cultural whaling,” Chris Yates, an assistant regional administrator with NOAA Fisheries, told The Post. “It’s been a real long time coming for the Makah tribe.”The waiver allows the Makah to hunt up to 25 Eastern North Pacific gray whales over a 10-year period. As of this spring, there were about 17,000 to 21,000 of the gray whales along the West Coast, Yates said.Western North Pacific gray whales, which remain on the Endangered Species List with an estimated population of 300, will not be included in the waiver, Yates said.“There are multiple safeguards built into this,” he said, adding that the hunts will take into account when the endangered whales migrate.DJ Schubert, senior wildlife biologist with the Animal Welfare Institute, told The Post that allowing hunting only adds to factors threatening gray whales. The sea creatures face a host of dangers, Schubert said, including entanglement, ship strikes, pollutants, contaminants and ocean noise. The climate crisis further endangers gray whales.“The population is at risk,” he said.While NOAA’s restrictions state that only Eastern North Pacific gray whales may be hunted by the Makah tribe, it could be difficult to distinguish between the eastern stock of whales and the western while out on the water, Schubert added. “We’re not convinced that the restrictions are sufficiently protective of these other groups of gray whales.”Greene pointed back to the Makah tribe’s decision to stop hunting whales when their population was at risk. Members of the tribe are responsible stewards of the land and its creatures, he said.“As important whaling was and still is to our people, we chose to lay down the harpoon when the resource was at a point where it wasn’t healthy,” Greene said.The first Makah whale hunt in decades could happen as soon as the fall, though it’ll probably occur next year, Greene said.The tribe and federal regulators need to enter an agreement, and the Makah must obtain a hunting permit. There will be restrictions on when and where hunts can occur, which would also be subject to change based on whale population sizes.The Makah must also finalize their own tribal regulations and organize a whaling crew. About 10 people who were on the last whale hunt in 1999 are still alive, according to Greene.Greene, 52, has never participated in a whale hunt. Decades of legal battles caused him and hundreds of other members of the tribe to miss out, he said.News of the waiver energized the community, which Greene said will prepare its canoes, paddles and harpoons for the Makah tribe’s sacred tradition.“It’s going to be life changing,” he said.

Is This the First Recorded Footage of a Colossal Squid Living Freely?

The only sightings of the animals so far have come from corpses or creatures dragged up from the depths

While scientists have seen colossal squid before—like this specimen examined by New Zealander researchers in 2014—their interactions have always been with animals that were either pulled from the depths, washed up on shore or otherwise removed from their natural habitat. Marty Melville / AFP via Getty Images This article is from Hakai Magazine, an online publication about science and society in coastal ecosystems. Read more stories like this at hakaimagazine.com. Just after 10 a.m. on January 6, 2023, in the Southern Ocean some 680 miles south of Argentina, Matthew Mulrennan’s underwater camera captured a one-of-a-kind sighting: There, roughly 575 feet beneath his vessel, a lone squid was propelling itself through the frigid water. With its outstretched vermillion tentacles, see-through body and faint blue bioluminescent glow, this five-inch-long squid is, potentially, the first colossal squid ever filmed in its natural environment. Video captured off Antarctica roughly 650 feet deep below the surface shows what might be a juvenile colossal squid living freely in its natural environment. It’s possible this is not a colossal squid but instead another kind of closely related glass squid. Video courtesy of Matthew Mulrennan / Kolossal Mulrennan, a marine scientist and founder of the California-based nonprofit Kolossal, has been working since 2017 to record footage of wild colossal squid (Mesonychoteuthis hamiltoni). Cephalopod experts are convinced Mulrennan filmed some sort of glass squid, the scientific family to which colossal squid belong. But they remain unsure whether it was a young colossal, an adult Galiteuthis glacialis or a previously unknown species in the closely related genus Taonius. The Antarctic water where Mulrennan’s team spotted the squid was full of marine snow, giving the video a grainy quality reminiscent of the first photos of another little-known cephalopod: the giant squid. Although both cephalopods are so elusive they’re practically legendary—and often compared to the mythical kraken—colossal squid have bigger, heavier bodies and slightly shorter tentacles than their giant brethren. While giant squid were first photographed and filmed in their natural habitat in 2004 and 2012, respectively, the only sightings of colossal squid have come from corpses or animals dragged up to the surface. Until, perhaps, now. Colossal squid were first scientifically described by zoologist Guy Robson in 1925 after a sperm whale washed up in the Falkland Islands with two colossal squid tentacles in its stomach. Since then, the massive animals have rarely been caught, photographed or even seen. That’s a striking feat for a creature longer than a cargo container with eyes the size of volleyballs. As adults, colossal squid are Earth’s largest invertebrates. They eat Patagonian toothfish (also known as Chilean sea bass) and are hunted by sperm whales. When they’re young, colossal squid seem to venture closer to the ocean’s surface, where they’re picked off by penguins, albatrosses, seals and Patagonian toothfish. Little else is known about their behavior; most clues are derived from fishing line nibbles, examinations of predators’ stomachs and the occasional squid corpse that washes up on a beach. William Reid, a marine biologist at Newcastle University in England, was lucky enough to get up-close with a colossal squid after fishers unexpectedly pulled one up in 2005 near South Georgia Island, located between Antarctica and South America. Although its several-feet-long mantle was too heavy to salvage, Reid’s incomplete 440-pound specimen revealed how the hooks and suckers that line the squid’s arms can pop off, giving the animal an impressive grip but also offering easy detachment from prey and predators. In the depths of the ocean where little light penetrates, Reid suspects colossal squid are ambush hunters that wait patiently for prey to wander within reach, then use their long arms to stuff their catches into their beaks. He says the squid’s giant eyes may be adept at seeing bioluminescence, which could alert them to hungry sperm whales coming their way. Colossal squid have been documented a few other times, too. Soviet fishers caught and photographed the first whole colossal squid in 1981 off eastern Antarctica. In 2003, fishers from New Zealand snared a dead 660-pound juvenile colossal squid in Antarctica’s Ross Sea, and then, in 2007, they pulled up a live 1,100-pound adult from a depth of almost 5,000 feet. And in 2008, Russian scientists caught one farther west in the Dumont d’Urville Sea. But no one has ever seen a colossal squid living, undisturbed, hundreds of meters below the surface where it naturally dwells. And, as Reid emphasizes, because colossal squid tend to collapse under their own weight when dragged from the highly pressurized deep sea, studying them in their natural environment is the only way to see both their behavior and fully intact anatomy. That’s why, from December 2022 to April 2023, Mulrennan and his crew set off on four multiweek trips from Ushuaia, Argentina, aboard the Ocean Endeavour, a tourist-packed expedition vessel operated by Intrepid Travel. Sailing alongside roughly 200 curious tourists, Mulrennan and the Kolossal team traveled to the South Shetland Islands, South Georgia, the Antarctic Peninsula and other areas below the Antarctic Circle in search of the oversized squid. While passengers slept and disembarked on day trips to see penguins, whales and Antarctica’s icy terrain, the researchers—including Jennifer Herbig, a doctoral candidate at Memorial University in Newfoundland and Labrador—took turns dropping a tethered underwater camera from one of the ship’s gangways into the freezing water below. “We’d put the camera in the water at midnight or 1 a.m., be up until 4 or 5 a.m., and then have to get up at 6 or 7 a.m.,” Herbig says. With the camera dangling as far as 1,300 feet underwater, it became a near-constant effort to keep it from getting hooked on sea ice and disappearing into the deep. In total, the team captured 62 hours of high-definition footage. Along with their prospective colossal squid, the scientists spotted a giant volcano sponge—animals thought to live up to 15,000 years—and dozens of other deep-sea Antarctic species. It was challenging work made easier by the ship’s other passengers, who brought the scientists cookies and hot chocolate during long nighttime deployments. Herbig, for her part, cherished the tourists’ interest. “They could just peek over our shoulders and see what we were doing, so we got to explain some of the science,” she says. “Every day on the ship, I was asked, ‘Did you find the squid?’” Mulrennan recounts. “People really want to know more about these large kraken-like species”—especially the ship’s chef, who kept joking about cooking the squid if they found it. Whether the video Mulrennan’s team captured turns out to be a juvenile colossal squid or not—that final determination depends on continued examinations by squid experts at New Zealand’s Auckland University of Technology—the Kolossal researchers aren’t finished with their quest just yet. While last year’s expedition relied largely on using an underwater camera to film close to the noisy vessel, the team hopes to revisit Antarctica as soon as November 2024, armed with a much broader suite of tools. Mulrennan is looking to upgrade from one underwater camera to as many as a dozen, which he can deploy simultaneously, and he wants to add remotely operated cameras that would enable filming farther from the boat. Another option for improving their technique, says Herbig, would be to get longer camera cables so they can peer even deeper into the colossal squid’s frigid domain. Herbig adds that they could also bring equipment to analyze environmental DNA and measure biomass, helping the team study the abundance of creatures that share this deepwater habitat. With a tattoo on his left arm commemorating zoologist Guy Robson’s 1925 sighting of a colossal squid, Mulrennan hopes to lead or inspire a verified underwater filming of a live, wild colossal squid by 2025. “If finding the giant squid was like landing on the moon, then finding the colossal squid’s going to be like landing on Mars,” he says.This article is from Hakai Magazine, an online publication about science and society in coastal ecosystems. Read more stories like this at hakaimagazine.com. Related stories from Hakai Magazine: Get the latest Science stories in your inbox.

Pigeons on the pill: scientists look to contraceptives to curb pest numbers

Birth control is being trialled as a humane way to limit growing numbers of grey squirrels, pigeons and wild boarThe invention of the contraceptive pill heralded the sexual revolution of the 1960s, and now scientists are looking to revolutionise wildlife control by getting animals in on the action.Trials are under way in the UK and elsewhere in Europe of how to get contraceptives into pigeons, wild boar and grey squirrels, with scientists also proposingother rodents, invasive parakeets and deer as other target species. Continue reading...

The invention of the contraceptive pill heralded the sexual revolution of the 1960s, and now scientists are looking to revolutionise wildlife control by getting animals in on the action.Trials are under way in the UK and elsewhere in Europe of how to get contraceptives into pigeons, wild boar and grey squirrels, with scientists also proposingother rodents, invasive parakeets and deer as other target species.As destruction from invasive and pest species grows, researchers are looking to fill special feeders and bait boxes with hazelnut spreads and grains laced with contraceptives. They believe this could be a more humane and effective way of controlling populations that have previously been poisoned, shot or trapped.The aim is to find “creative solutions”, says Dr Giovanna Massei from York University. “The main message is that the economic and the environmental impact of wildlife are increasing worldwide, and we are running out of options,” she says. “Traditional methods such as culling are ineffective, can be inhumane, unsustainable, environmentally harmful, and are increasingly opposed by the public.”Grey squirrels are a particular issue for the UK. These non-native animals were first introduced from the US to England in the 1800s as an ornamental species for stately homes. However, they spread widely, causing local extinctions of the native red squirrels and damaging woodlands by stripping bark. The species is estimated to cost £37m a year in lost timber in England and Wales. Grey squirrels are seen as a bigger threat to broadleaf trees than deer and pathogens, according to a Royal Forestry Society survey.Trials are under way to deliver oral contraceptives hidden in a hazelnut spread for squirrels in the UK, using specially weighted feeders that only grey squirrels can open (red squirrels are lighter, so the trap will not open for them). Preliminary results suggest the method is working.Pigeons could be fed a “breakfast” of corn grains containing the contraceptive every morning, said Dr Marco Pellizzari, a veterinary consultant. “They really love to get that … It’s very easy,” he says.In London, the non-native parakeet could also be a recipient, but it would mean asking residents who routinely feed them in their gardens to give them food with contraceptives in it.Next week York University will host the first workshop on wildlife fertility control, where experts and researchers involved in the trials will discuss how to deliver contraceptives to pests – animals considered harmful to people, farming or native habitats.A wild boar in Rome. Continental Europe has seen a rapid increase in the animals, considered pests by Italian farmers. Photograph: AFP/GettyAcross continental Europe and Scandinavia, there has been a rapid increase in wild boars, with the rise in numbers believed to be linked to milder winters. Some consider them pests because they root up cropland, munch through rubbish and cause traffic accidents. Italian farmers’ associations say the wild boar population doubled from 500,000 in 2010 to one million by 2020. In Germany and in France, more than half a million are shot every year, but numbers are increasing, and the number of people who want to hunt them is declining. Massei says culling is “clearly not controlling a number of these animals”.A pilot programme is under way to look at giving them contraceptives using devices that only boar can lift up, using their burrowing snouts. The feeder works but the oral contraceptive has not yet been developed.Many countries are now banning the use of rodenticides because of their impact on other animals, including birds of prey, which have died from eating the poisoned carcasses. The chemicals are also considered inhumane, as animals can suffer for several days after eating anticoagulants before they die. Glue traps have been banned in England, Scotland and Wales, and other sorts of live traps will probably be further regulated, according to Prof Steve Belmain, an ecologist from Greenwich University.Yet rodents pose significant threats to agriculture, as well as transmitting diseases to livestock. “We don’t have many alternatives to lethal control. That’s where fertility control really could be a great opportunity to manage these things,” says Belmain.Feral horses in the US are already on contraceptives, as well as African elephants outside Kruger national park, who are injected. The only contraceptive registered for use in Europe is nicarbazin, which is only allowed to be used on pigeons in a few countries such as Italy, Spain, Belgium and Austria.A regular gathering point for pigeons near Oxford Street in London. Photograph: Mike Kemp/In Pictures/GettyResearchers are also looking into the possibility of giving deer contraception, but so far no orally administered one has been designed for grazing animals. Britain has more deer than at any point in the past 1,000 years, causing extensive damage to woodlands.There is concern that using products based on synthetic hormones could result in oestrogenic chemicals getting into the environment, which has negative effects such as feminising male fish. It is also not known what the impacts would be on a predatory bird if it ate a rodent that had eaten a contraceptive. “We need to really understand these things as part of that regulatory process,” says Belmain.

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