The Science of Restoring Wolves to Colorado
This article is part of our ongoing series Wolves in Colorado: Science & Stories, a special five-part virtual presentation of the Institute for Science & Policy and Colorado State University’s Warner College of Natural Resources, in partnership with the Center for Collaborative Conservation, the Center for Human-Carnivore Coexistence, CSU Extension, and the Denver Museum of Nature & Science. Watch the full recording of the session, register to attend our upcoming sessions and find full recordings and recaps of all episodes archived here.
In our premiere episode, the Institute’s Senior Policy Advisor Kristan Uhlenbrock was joined by Stewart Breck, Research Wildlife Biologist, USDA Wildlife Services; Kevin Crooks, Director of the Center for Human-Carnivore Coexistence and Professor in the Department of Fish, Wildlife, and Conservation Biology at Colorado State University; and John Sanderson, Director of the Center for Collaborative Conservation at CSU. The panel discussed wolf-related policy and the latest ecological and social science research pertaining to wolf ecology, interactions with big game and livestock, and public perceptions of wolves. For generations, wolves and humans have navigated a fraught dynamic of coexistence. What does the science tell us about the pros and cons of wolves returning to our backyard? And, if wolves are in Colorado’s future, how can society have an effective dialogue that uses science to inform policy and management?
This transcript has been lightly edited for length and clarity. Watch the full recording of the session here.
KRISTAN UHLENBROCK: Welcome to our audience tonight, and to my co-host John Sanderson, the director of the Center for Collaborative Conservation at Colorado State University. John has been instrumental in helping put this series on and is quickly becoming a dear friend.
JOHN SANDERSON: Thank you, Kristan, the feeling is mutual. Thank you all for joining us tonight. I'm really excited about this series. It's been a lot of fun putting it together. What prompted this webinar series, as most of you know, is a ballot initiative for November. It was originally referred to as ballot initiative 107 and is now Proposition 114 with the title “Reintroduction and Management of Gray Wolves.” Proposition 114 directs the Colorado Parks and Wildlife Commission to develop a plan to restore and manage gray wolves and take the steps necessary to begin reintroductions of gray wolves. on the Western Slope by December 31, 2023. The proposition also requires the commission to seek public input, assist livestock owners with preventing and resolving conflict between wolves and livestock, and to compensate livestock and owners for loss of livestock caused by wolves.
Now, this series won't tell you how to vote, but we hope it helps make an informed decision. You're going to learn a lot through this series about the complexities around this issue, and how science can inform it, and also how in many ways it's much bigger than science as well. The solutions, at least we can say, will require more than science. It will require figuring out how we work to navigate a contentious issue. We're eager to know if the series has helped you understand and engage in this complex and challenging issue.
KU: Thank you, John. So let me introduce and welcome our two special guests this evening, who actually have been very thoughtful in putting this series together too. I'm excited to hear from them both tonight. Dr. Kevin Crooks is the director of the Center for Human Carnivore Coexistence and a professor in the Department of Fish, Wildlife, and Conservation biology and a graduate degree program in ecology for Colorado State University. Good evening, Kevin – how are you tonight?
KEVIN CROOKS: I'm doing great. Thanks for the introduction. I should say that it's a pleasure to be back at the museum, because I actually grew up in Denver, and I went to the museum many times as a kid. On field trips I remember the buses rolling in, all the kids pouring out. I distinctly remember the sabertoothed cat that you put the coin in and it would roar. It was always a crowd favorite. So I just wanted to say that it's true to say that both the museum and the Denver Zoo were really informative, for me in developing my appreciation for wildlife science. It's a pleasure to be to be back.
KU: Our other guest this evening is Dr. Stewart Breck, a researcher for the USDA National Wildlife Research Center. His research has focused on carnivore ecology and behavior and minimizing conflict between carnivores and people. He received his PhD in ecology from CSU and his studies include testing non-lethal methods of preventing conflict, measuring the impact of carnivores on livestock influence of urban environments on carnivore ecology and population biology, and behavioral ecology of carnivores. Good evening, Stewart – how are you?
STEWART BRECK: I'm doing very well, thank you Kristan. And thank you all for being here. I would say, unlike Kevin, I am not a native of Colorado. I grew up in Texas, so please don't hold that against me. I discovered fishing in Colorado as a young child with my grandfather and that experience just made me have to move to Colorado and that occurred in 1987 by attending CSU. I'm really happy to be here and sharing this experience with all of you.
KU: So let's get into the meat of this. John and I are going to take a backseat while the two of you walk us through some slides and so I think Kevin you're going to kick us off first here.
KC: First, just let me give you a little bit more background about myself. I'm a wildlife biologist and much of my work has focused on carnivore ecology, including mountain lions, bobcats, coyotes, foxes, bears and wolves. I'm also a director of the Center for Human Carnivore Coexistence at CSU. We're a team of social and ecological scientists, and our mission is just to develop approaches to minimize conflict, and to try to facilitate coexistence between people and predators and that includes wolves, if they're restored to Colorado.
On another personal note, I have deep roots here in the Rocky Mountain West. On my mom's side, from an early pioneer family in Wyoming, my great grandmother was born in the Wind Rivers in the late 1800s. Her son, my grandfather, like myself is also a wildlife biologist. He started out as a hunting guide around Teton. He eventually became the state Game Warden in Wyoming and then served on the state Wildlife Commission, and he was an ardent opponent of wolves. He and I had many discussions about this topic. So I feel like I understand his perspective, and why people, particularly in rural communities might have negative perception towards wolves.
Today, Dr. Breck and I are here as scientists who feel that science should help guide wildlife management and policy. So we're not here to advocate for or against the ballot initiative, but rather to provide scientific information on the issue. Fortunately, wolves are very well studied and there's a large body of scientific knowledge to help guide these kinds of discussions and decisions. So what are the prospects for wolf restoration in Colorado, and what does the science tell us? Well, we know that wolves were once distributed throughout Colorado, but were eradicated from the state by government sponsored predator control by the 1940. So for the most part, wolves have been absent from the state for the last 75 years.
But science tells us that Colorado still supports suitable habitat for wolves. Wolves can live in a variety of habitat types and they can persist basically where there's enough prey, and where they're tolerated by humans. The best habitat for wolves is on public lands where both of those needs are met. Colorado has over 24 million acres of public lands, mostly on the western slope. It also supports a large population of mule deer and elk which are the primary prey of wolves and one of the best predictors of wolf habitat quality. In fact, Colorado Parks and Wildlife estimates that Colorado supports over 280,000 elk, which is the largest elk population of any state, and it also supports over 430,000 mule deer.
Multiple scientific studies have concluded that Colorado can still support a viable population of wolves. In fact, a review published several years ago by Dr. David Mech, one of the world's foremost experts, specifically identified Colorado as being primed for wolf restoration, particularly the western slope. Now wolves are listed as an endangered species under the Endangered Species Act through the US Fish and Wildlife Service. They're also listed as endangered by the state of Colorado. An important conservation goal for endangered species is that they recover to form a self sustaining or viable population and a viable population is one that has sufficient numbers and distribution, such that it has a high likelihood of persisting over the long term.
As some of you have probably heard, over the past year, Colorado Parks and Wildlife has documented a pack of up to six wolves and then another lone wolf in northern Colorado. This small number of wolves in one part of the state would not be considered a viable population. These wolves are also at risk. They might be killed or simply disappear as has happened to the few other wolves, that have migrated to Colorado over the past couple of decades. Indeed, there's recent reports that some of the Colorado wolves may have been shot and killed on the Wyoming side of the border. And while protected in Colorado, wolves in Wyoming have no legal protection in most of the state. That means they can be killed on sight with no hunting license and no hunting season. So this makes it more challenging for wolves to migrate from Yellowstone through Wyoming into Colorado and therefore lowers the likelihood that of a viable population arising from natural migration.
Ultimately, if Colorado wants to restore a viable population of wolves to the state - if that's the goal -then active reintroduction by wildlife managers would improve the odds of achieving that goal. These kinds of reintroductions have occurred for grey wolves in Yellowstone, and for Mexican wolves in Arizona and Mexico, and for the red wolf in North Carolina.
So if wolves did return to Colorado, what might be the impacts? One concern sometimes expressed is the direct threat of wolf to human safety. What do the facts tell us? Well, we know that in North America since 1900, there's only been two cases of wild wolves killing humans: one in Canada and the other in Alaska. No humans have been killed by wolves in the lower 48 since 1900. Generally, wolves typically avoid humans and direct encounters are therefore rare. Overall, wolves represent little direct threat to human safety.
Now, another consideration is the potential impacts of wolves on big game populations and therefore hunting opportunities. So again, what does the science tell us on this? Numerous scientific studies indicate that under certain conditions, wolves can contribute to local decreases in prey numbers. This is especially true when wolf predation is acting in concert with other factors that also limit the game such as harsh weather, severe winters, and human hunting. If so, this could impact hunting opportunities for some areas. But wolves, big game, and hunting can and do coexist, as demonstrated by abundant big game and hunter harvests in states with wolves, including in Alaska, the Great Lakes states, and the northern Rocky Mountains.
We can actually look to the northern Rocky Mountains for some insights on this issue. Data taken from Montana Fish, Wildlife and Parks shows that the number of elk harvested by hunters has not declined over the past 20 years, despite a significant increase in wolf populations in the state. And these same trends are evident at a statewide level for both Idaho and Wyoming. That's a statewide level. Now, at a local level, the effects can vary. For example, the data show us that elk numbers are stable or increasing in some areas where wolves and elk interact around the Yellowstone region, but in other areas, elk numbers have declined due in part to wolf predation. So if wolves were fully restored to Colorado, we might expect something similar. We might expect local impacts on some herds and some hunting opportunities, particularly when predation is acting in conjunction with other factors that limit the big game. But we would not expect a large impact on big game and hunting at a statewide level.
And finally, there's been considerable discussion about the ecological impacts of wolves, the potential for this top predator to generate effects that ripple through food webs. Studies, primarily in Yellowstone, have suggested that wolves might help reduce overcrowding by elk and deer, which may allow vegetation to recover and improve habitat for other animals such as songbirds or beavers. But science also tells us that the systems are very complex and wolves were likely not solely responsible for the types of ecosystem changes that have been documented in Yellowstone over the past 20 years since the reintroduction. It's also unclear to what extent those kinds of impacts might translate to other systems outside of national parks, including in Colorado.
So, in short, it's a complicated story, but what we might expect in Colorado is that wolves might have noticeable ecological effects where they occur in high enough densities for a long enough time. But in other areas with lower density rate, the ecological effects will be less evident. Ultimately wildlife managers have a variety of tools when it comes to predators, big game, and hunter harvest. For example, regulated hunting of big game and predators can be manipulated to achieve management goals. Science also indicates that habitat quality is often a stronger driver of populations that is predation. So another option is to protect and to manage big game habitat to ensure thriving herds. And then finally, scientific monitoring of big game and predator populations can help ensure that the numbers of predators and prey on the landscape achieves the desired balance.
At this point I'd like to turn it over to my colleague and friend, Dr. Stewart Breck, to talk about the impacts of wolves and livestock.
SB: Thanks, Kevin. I'm a research biologist with Wildlife Services at the National Wildlife Research Center. I do a lot of work in conjunction with Kevin and others at CSU. Wildlife Services plays a big role in managing wolves, particularly the potential conflict that can occur between wolves and the livestock industry. That's where I will focus my talk tonight.
I've been at the National Wildlife Research Center for 20 years, and I was hired to develop non-lethal tools, specifically for wolf management, but also other carnivores as well. So I've spent a lot of time in Arizona, New Mexico, Idaho, Montana and places like that, developing tools, testing tools, and learning more about wolves. So I wanted to cover two things tonight. One of the questions is: What are the impacts of wolves on livestock? And then secondly: What can we do to minimize the impacts?
If we look at impacts of wolves on livestock, there's various ways of looking at it. One way is to take data from the state of Montana and mortality that occurs to livestock. You'll see about 1% of unwanted losses are caused by wolves. And then if you ask, of the approximately 4 million cattle, how many die by wolves, that accounts for less about 0.02% of total inventory. And so you could conclude from that that wolves don't really have much of an impact.
But hold on: that's maybe not a fair way of looking at things. And I say that because the impacts of wolves on the livestock industry are very localized, meaning some producers are going to have a lot of impact. A direct impact is when a wolf comes into livestock and kills a cow or sheep or something. And we are able to quantify that. A lot of times, though, we have livestock on the landscape where they may be killed by wolves or other predators, and we just don't know about it. So those are unmeasured direct impacts. There's also indirect impacts that are also hard to measure, and those might be the impacts of wolves on the behavior of livestock. Does that influence their weight gain? Does that influence their pregnancy rates? Things like that.
And then, the thing that's often not captured in the statistics is that there's a real emotional component to these predation events. It’s a reality of having wolves on the landscape. This will occur in Colorado. Wolves do prey on livestock and sheep and guard dogs, so livestock guard dogs are common across landscapes to protect particularly sheep, and occasionally they can confront wolves and be killed. Sometimes my agency has to euthanize wolves. And so the question I really want to focus on tonight is: what can we do to minimize these impacts, how can we minimize the number of wolves killing livestock, and then how can we minimize the need to kill wolves?
The first step in this is that we really need to start with accurate data collection. That means having trained personnel that are able to basically do a CSI-type investigation when there's dead livestock on the ground. And this is a really stressful job. You need somebody that's trained in necropsy, able to skin out these dead livestock and look for the signs that indicate predators. They're taking a lot of evidence from around the kill site. There's a lot that goes into this. There's also a tremendous amount of pressure. Oftentimes you have a rancher watching you, there's pressure to say yes, this is a wolf kill, especially if there's a compensation program in place. My point here is that you really need some professionals that are good at taking the pressure and are good at their job. Wildlife Services does a lot of this work, but so do state game agencies. This is a critical first step in having wolves on the ground.
The second thing I want to talk about is, is being able to predict where we’re more likely to have wolf-livestock conflict. In the project I was involved with in Arizona and New Mexico, we were able to take what we know about where wolves are, where elk, and where deer are, then we can overlay that with where we know the livestock are. This allows us to see the hotspots and then we can apply resources in a proactive way. Get in there early, start working with people, help them understand how what it's like to live with wolves.
A big part of my job and a big part of what still needs to be done is developing and evaluating management tools. There's a whole lot of things out there that we can use to prevent interactions between wolves and livestock. That might include barriers and scare devices or utilizing guard dogs. My agency does a lot of work with developing larger guard dogs that are maybe better able to deal with wolves versus some of the guard dogs that are more standard for use guarding against coyotes. We've done work on looking at human presence, like range riders out on the range or shepherding. Owners are willing and able to alter grazing strategies sometimes, and that can help reduce attractants on the ground. All these are things that we can do to help minimize conflict.
I also want to emphasize that lethal control should be on the table. It is something that can be an important management tool in certain situations. Now, lethal control is something that no one really wants to do. Sometimes it's necessary, but if you pull it off the table, that’s a mistake.
A tool is only as good as a person using it. We can we can have all these tools in our toolbox. But if people are not willing to implement them in the proper way, then the tools may be less effective.
There's a lot of inertia against the use of new tools. It's not a simple thing. But there are some good examples of people coexisting with wolves and other large predators on the ground. I want to use this example out of Montana. I'd encourage you to look at the Blackfoot Challenge. This was a group of ranchers that started working together, and they recognized that there's a lot of environmental problems related to water use, forestry management and living with large predators. And so they came together, they invited federal agencies, state agencies, and NGOs to all work together to try to solve these problems in a different way. It's been very successful. We see very low numbers of livestock losses, low numbers of wolves killed, and a good self-sustaining population of wolves in this area. That's what we're shooting for with coexistence. Part of what the Blackfoot Challenge does is a lot of preventative work. They clean up carcasses off the landscape. They use range riding, and other non-lethal tools in a real preventative way. They're a very successful model.
This issue is often divisive with strongly opinionated groups that are loud and powerful. And so how we handle that is a real important challenge and it really comes down to people and not necessarily wolves. If Colorado chooses to restore wolves or the wolves are allowed to return here, I believe we have a choice. We can have a really hot flaming inferno of conflict between people yelling at each other and a lot of hateful statements made towards each other and a lot of litigation. Or, we can have sort of a slow burn, where we accept there's going to be problems, but we can handle them in better ways. And it requires cooperation. It requires people working together and it requires utilizing the tools we have and utilizing them in a smart way.
And so how do we achieve that? Purposeful gathering of stakeholders that are really passionate about this idea of wolves in Colorado. We need those people to come together and to talk it out to find the compromise, find where we can work together. Combine resources so that the ranchers are not as impacted. So, I have a lot of actual hope if Colorado goes that way that we can move in this direction and really the science that needs to be done is more about the people than it is about wolves. We know how to bring wolves back. What we need to really focus on is how can we bring people together.
KU: Thank you, Stewart. Thank you, Kevin. I'm wondering if you could speak to maybe one major misconception that you've read or that you've heard that you'd like to clarify.
KC: Well that's a very good question. You know, one of the reasons why we've decided to engage on this issue is that there is so much misinformation out there on all sides about this issue. In general, I’ll say that the effects of wolves tend to be overplayed and tend to be exaggerated. And I'd say the biggest disconnect between what people perceive might happen and what the reality is regarding wolves is about that human safety issue, the direct threats of wolves to humans, the fear that they might attack people or attack our kids. That is something that we've found often comes up in public discourse and in media coverage on this issue. I'll put in a quick plug for my colleague, Dr. Becky Niemiec, who will be talking next week at this webinar, about some of her social science work analyzing media portrayals of the wolf issue. And this human safety issue often comes up when in reality, wolves are a low threat to people. 4 million people visit Yellowstone every year, including a lot of tent campers, and there's been no instances of wolf attacks.
SB: There's a perception among some stakeholders that if you have these non-lethal tools, that they'll always work and that that's all that we need to solve this. It's just not that easy. There are some good tools, but they require some finesse, they require some education, they require some new ways of thinking to really make them work effectively.
KC: Just in general, I would say a misperception is that they're going to have larger impacts than they probably will. Impacts to big game, impacts to livestock, impacts to ecosystems, the top down effects of these wolves - I think they're often exaggerated. You know, it's interesting. Wolves evoke such strong passion and polarization. And we have a long history of humans have living with wolves. So I think that that's part of the issue here, that this is really deep. There's a lot of mythology about wolves and therefore those misperceptions and mythology has kind of gone through us for generations.
JS: Kevin, I was wondering if you could explain to us a little bit about the policy context in which we're operating right now. Proposition 114 will direct the Colorado Parks and Wildlife Commission to reintroduce wolves to Colorado. Colorado Parks and Wildlife is not here on tonight's panel. They have extraordinary wildlife expertise, but they're not here because this is a ballot proposition and they can't speak on such things prior to the vote. But in their absence, can you tell us about the status of wolves right now and then, if the ballot initiative passes, what is the role of Colorado Parks and Wildlife and Fish and Wildlife Service and other agencies?
KC: Yes, and this often gets confused in the discourse about this issue. And it's sort of complicated, but I'll try. Right now, any wolves in Colorado are still considered endangered under the US Endangered Species Act. That means that the federal government and specifically the US Fish and Wildlife Service has management authority of wolves, not Colorado Parks and Wildlife. That includes any wolves that naturally migrate into the state, as long as wolves are listed under the ESA. Now, if Proposition 114 passes and if wolves are still listed as endangered under the ESA, then a permit for reintroduction would be required from the US Fish and Wildlife Service from the feds to do the reintroduction. If that permit is secured, then Colorado Parks and Wildlife would be responsible for developing and implementing the, the wolf reintroduction plan. A
Another reason why this is sort of complicated - and it's a fluid situation right now- is that that the US Fish and Wildlife Service now considers wolves to be stable and healthy through their current range in the lower 48. So they've concluded that the gray wolf is not in danger of extinction and therefore should be removed or delisted from the Endangered Species Act. Back in spring of 2019, they proposed to remove all gray wolves in the continental United States, except for the subspecies of Mexican wolf, but from protection under the ESA. So if that happens, if they are delisted from the Endangered Species Act, this would then turn management back to individual state wildlife agencies. I hope that was clear.
JS: I think so, thank you. It's complicated.
KC: If you read the news, the Trump administration has suggested that they are going to try to push through delisting the wolf from the Endangered Species Act. It could happen sooner rather than later. And so, it puts in some uncertainty.
KU: I want to build on that a little bit so we can get into the technical details about numbers. An audience member said that there was an article in the Colorado Sun that a self sustaining population is between 80 and 100 wolves. So I'm curious, how do we conduct the census of wolf population? What is that target for a self sustaining population?
KC: I don't think that the scientific studies have been conducted yet to fully know what a viable population of wolves would be in Colorado, or how many wolves Colorado could support in total, so I haven't heard that 80 to 100 number before.
What I do know is that currently, Colorado Parks and Wildlife has estimated that there’s four wolves in the state and that certainly isn't a viable population. But I think it's yet to be determined how many wolves Colorado could support. There have been some studies - all somewhat dated now, about 15 years ago - suggesting that Colorado could support at least 400 wolves. And that was even after projecting future human population growth. We could still do more work to try to estimate how many wolves Colorado could support. But I think it’s important to state though that Colorado can still support a viable population of wolves. There is enough habitat, there is enough prey.
SB: I don't know how much good data there is to support, saying that if it’s such and such population number, you're going to have this much growth and conflict. But I do know that from different states like Idaho, Montana, Wyoming, they all reached their population goal when they were going through the recovery phase fairly rapidly. And once that happened, every state was interested in implementing some type of hunting program so that they could primarily use that as a way to control the population numbers. And each state is different in what they've done, and that action itself is quite can be somewhat controversial, but it's something that we've seen in those states, for sure.
JS: Stuart, can I ask you a little bit more about lethal control? We've had several of our listeners ask why does a wolf get killed, and who makes that decision. And one thing I'm personally kind of curious about is whether wolf packs have culture and behaviors that can be passed along.
SB: Yeah, so there's a lot to unpack there. Often, part of the decision looks at the size of the wolf population. If it’s a small population, you’re going to have more of an effort not to remove wolves. In all the states that recovered wolves in the Northern Rockies, there's a tremendous amount of effort trying to develop non-lethal tools to prevent the livestock conflict. But as that wolf population grows there's going to be more leeway to remove wolves.
Do wolves have culture? I think I'll kind of reframe your question to: do wolves learn? There's pretty good science to support yes. Once we see a wolf learn to kill sheep or cattle, that pack of wolves will see a recurrence of that behavior. And, in fact, this is a really important point to the use of non lethal tools. You have to be in there before these occurrences happen, before a wolf kills livestock. After that happens, then you're behind the eight ball immediately, then it becomes much harder to make these tools effective. So that whole process of wolves transferring behavior within individuals is an important component of all of this. And we've learned that over time. There's been a lot of recognition of that and a real emphasis on getting the resources and the tools out to the producers before we start having problems
It's something that we're really keen on engaging here in Colorado. We should be out at the front of this with education. What are these tools out there that are available and how can we prevent some of this? Because you're right, once wolves learn to kill livestock, nonlethal tools start shrinking in terms of effectiveness. And then we have to rely on lethal control.
KU: Let me pick up a little bit on that and shift our conversation a little further. You both spoke a little bit about bringing people together to the table and this idea of co-creation. Where can we go with that so that things feel like they're very useful to the communities or to the producers that need that information?
KC: I think there's a growing movement in science - and maybe not specifically academic science but certainly in academia - to not just generate knowledge ourselves and then disseminate that knowledge, but rather work collaboratively with diverse groups to co-produce knowledge to ensure that science is translated to real world action. That really requires working together with a diverse groups. When interdisciplinary scientists, practitioners, stakeholders and all sides of the issue work together from the beginning to formulate the questions in science, that can help increase the probability that the science we conduct is ultimately accepted and used in the real world. Because ultimately, that's our job.
We have to do a better job of disseminating our science, of linking our science to policy, of moving beyond the ivory tower. And I think wolves are actually a really good example of that. I mean, wolves are a highly contentious issue, it's hotly debated. There's a lot of misinformation out there and so our team up at CSU felt that the general public and policymakers would benefit from a reliable source of science based information on wolves. CSU specifically is a land grant university. A key mission of a land grant institution is to apply knowledge to directly benefit the citizens of the state. It's literally part of my job description. I teach college students. I do scientific research. But another part of my job description is outreach and engagement to the real world. And I think that often, that is overlooked.
To be honest, looking in the mirror within academia, I think now perhaps more than ever, we can argue that science needs to inform policy. I know that that's what you're doing with your Institute for Science and Policy. We can look to COVID, we can look to climate change, we can look at the wolves where science can actually help inform some of these decisions.
SB: Being in this field for 20 years, I can say that when I first started, it was a hateful relationship between environmental groups and ranchers and there was a lot of litigation about what Wildlife Services would do. But over time, what's been really interesting to watch and experience is how some of these groups have started embracing this notion of working with producers on the ground and with the state agencies. There may be decisions made that they don't like, but for the most part they know we're able to bring resources, energy, and experience to the idea of coexisting with carnivores.
Some interesting strange relationships, if you will, have developed that are very meaningful between Wildlife Services and some of these NGOs, as well as Wildlife Services in the agricultural community. And that's an important target for people to aim for. That's what I would push for: how can we find that common ground to work together. It's a hard thing to do because there's a lot of inertia against that. Some of the producers probably don't want to be bothered with this, probably don't want to have to deal with this new kind of animal on the landscape. And so some of that just takes time and patience and, you know, taking the time to spend with these people to learn what they're dealing with.
KC: Going back to some of the science, wolves are one of the most well studied carnivores out there on the planet, and they occur globally in the Northern Hemisphere. And throughout the range of wolves, the scientific studies have indicated that human tolerance of wolves - the degree to which humans will tolerate them on the landscape - is the key determinant if they can persist in an area.
So as Stewart said, a key takeaway I would have is that wildlife management is more about people than it is about wildlife. That is definitely the case with wolves. Ultimately, if wolves are restored to Colorado, these kinds of collaborative approaches that incorporate a range of stakeholders are going to be really important not just to minimize conflict between people and wolves, but importantly to minimize conflict between people about wolves. I know that that's something that you all will be talking about next week and then in subsequent webinars.
JS: Just another biological question: a couple of our listeners wonder about the role of wolves in disease transmission or what happens if they eat an elk with chronic wasting disease. Can you say a little about that piece of the puzzle?
KC: I am not a wildlife vet, but I know some, so maybe I could talk to Chronic Wasting Disease briefly. CWD is a contagious, fatal neurological disease found in ungulates like deer and elk moose. It's a relatively widespread in in Colorado. Two points to make here: One is that wolves are predators and chase prey. And so they tend to target slower, more vulnerable individuals, including sick or diseased animals. One modeling study suggested that this kind of selective predation of wolves targeting animals might help limit CWD, compared to hunting by humans. Okay. But that hasn't been field tested. There is one interesting field study, actually, in Spain that shows that wolf predation on sick wild boars helps to control tuberculosis.
Now, we do have some field sites here in Colorado actually in part conducted by Colorado Parks and Wildlife in the Front Range of Colorado, showing that mule deer killed by mountain lions were more likely to be affected with CWD than mule deer killed by hunting. So it's sort of an interesting analogy. Mountain lions are ambush predators and they sit and wait for prey, so they're actually less likely to target diseased animals than wolves. So that's the first part, just quickly. The second part is that CWD is an organism that can remain infectious in carnivore feces, so it can be spread, but is degraded in their digestive tract. That data so far suggests that the wolves themselves wouldn't necessarily spread CWD across the landscape.
KU: I’d like to give each of our guests a few moments to give some closing thoughts.
SB: My hope would be that we do things differently in Colorado, if in fact the ballot measure passes, or even if it doesn't. That we cannot have so much of the vitriol and the hatred, if you will, that's associated sometimes with wolves. And I think we know how to do that.
KC: Thank you for attending and for hearing us. I would encourage everybody to educate themselves on this issue and hear people with other opinions because I think that's really important. Of course as a scientist, I'm hoping that people are more informed about the science. So as a plug, again, go to our website for the Center for Human Carnivore Coexistence and there's a lot of information there about the science behind the wolves issue.
There is a lot of talk about wolves restoring balance to the ecosystem. What is out of balance?
In this context, when people refer to an ecosystem as “out of balance”, they are likely referring to ecological changes due to the loss of apex predators at the top of the food chain. The decline and disappearance of large predators can cause “trophic cascades” - ecological effects that ripple through an ecosystem. A growing number of studies globally have documented trophic cascades generated by apex predators.
As discussed during the presentation, multiple scientific studies have suggested that wolves, as apex predators, can have substantial ecological effects. Most such studies have been conducted in national parks such as Yellowstone and Isle Royale in the U.S. and Banff and Jasper in Canada. These studies indicate that wolves have likely contributed to willow and aspen recovery and overall habitat diversity by reducing overbrowsing by elk. In turn, this can improve habitat quality for animals such as songbirds or beavers. However, some researchers have questioned if wolves are solely responsible for the changes evident in the Yellowstone ecosystem since wolves were reintroduced 25 years ago. They conclude that additional factors such as drought, harsh winters, other predators, and human hunting also contributed to the decline of the Yellowstone elk herd.
Overall, studies emphasize that understanding trophic cascades in large complicated ecosystems is challenging. Although loss of predators can cause ecosystem-level impacts, reintroduction of carnivores, including wolves, doesn’t always fully restore degraded ecosystems.
The ecological effects of wolves are difficult to predict, particularly outside of national parks. In parks such as Yellowstone, wolves and their prey are typically protected from many human disturbances, such as hunting, predator control, and habitat loss. Within parks, wolves are more likely to occur in abundant, stable populations. This likely increases their ecological effects. Outside of parks, wolves are often more heavily impacted by people and their density is often lower. This might lessen their ecological effects.
For more information, please the CSU Information Sheet on Ecological Effects of Wolves
What exactly would you consider to be a good opener for dialogue with an opponent of reintroduction?
Talking with friends, neighbors, co-workers, land managers, and policy makers about critical issues, such as wolves in Colorado, is normal and necessary. For many of us, it can be challenging to be open to new information and viewpoints, so how can we engage in meaningful dialogue about wolves in Colorado? Social science research suggests that encouraging others to think about their important values before receiving new information can reduce their defensiveness and increase their acceptance. So, before talking about wolves, try talking with the other person about land, water, home, family, recreation and other important values. Another approach is to frame an issue in terms of what the other person cares about about. When talking about wolves, consider that your audience may care specifically about wolves, or they may care more about wilderness, hunting, ranching, or recreation. Try asking how wolves relate to those things. Another strategy is to say something positive and respectful about the other person’s point of view before presenting new information or arguments. Finally, highlight the scientific consensus around an issue. For example, if someone is concerned about the threat of wolves to human safety, you could point out that data on wolf attacks indicates that risk of wolves attacking or killing people is very low.
For more information, see the CSU Information Sheet on Dialogue and Social Conflict about Wolves
What could be potential impacts of a continuing drought and climate change on prey and wolves that would impact a successful wolf introduction?
This is a good question, and one that is difficult to address concisely and simply because the potential effects of climate change on wolves and prey are complex and difficult to predict.
However, we do know that wolves use many different habitat types, from Arctic tundra to forests, grasslands, and deserts. In fact, historically, wolves were the most widely distributed land mammal on earth, living through most of the Northern Hemisphere. Wolves also can feed on a variety of prey, primarily big game, but also small mammals, insects, and berries. This adaptability – their ability to persist in a variety of environments - might lessen the impacts of climate change on wolves.
So, this is complicated question with no simple answers. More research is necessary to predict and better understand potential impacts of climate change on wolves and their prey.
Join us next week on Thursday, Oct. 1 for part two in the series: Media Coverage and Public Perspectives on Wolves, featuring Colorado Public Radio reporter Sam Brasch and CSU Assistant Professor of Human Dimensions of Natural Resources Rebecca Niemiec. Registration is open now.
Director of the Center for Human-Carnivore Coexistence and Professor in the Department of Fish, Wildlife, and Conservation Biology at Colorado State University
The Institute for Science & Policy is committed to publishing diverse perspectives in order to advance civil discourse and productive dialogue. Views expressed by contributors do not necessarily reflect those of the Institute, the Denver Museum of Nature & Science, or its affiliates.