Invasive Species and Yellowstone Wolves
Are the wolves of Yellowstone National Park an invasive species?
Conceptualizing Wildlife Management
The management of wildlife and natural resources is a polarizing subject with many voices involved. Frequently, biologists, ecologists, and federal agencies find themselves at odds with animal rights activists and even ranchers and hunters, depending on the situation.
Most discussion surrounding invasive species has to do with not-so-glamorous organisms like insects, fish, and plants. However, these discussions get more complicated when we start to question what it means to be an 'invasive species.' According to the National Wildlife Federation, an invasive species is, "any kind of living organism [that] is not native to an ecosystem and causes harm" (Invasive, p. 2). Although this definition may seem fairly black-and-white, it raises the question of what it means to be native to an ecosystem.
How long does it take for a species to become native to an ecosystem? Furthermore, how long would a species have to be absent from its 'native' ecosystem in order for it to be considered non-native? Ecosystems continuously adapt and change depending on myriad factors, which is why these questions are not easily answered.
By way of examining the reintroduction of gray wolves (Canis lupus) into Yellowstone National Park, the complications surrounding conservation biology, invasive species, and animal activism can be most clearly discussed.
Wolf Reintroduction
In 1995 and 1996, gray wolves were reintroduced to Yellowstone National Park after having been absent in the park for seventy years; the last wolves in Yellowstone before the reintroduction were shot by park rangers in 1926 (Blakeslee, p. 14). In the nineteenth century, the federal government employed a 'predator control program' in which they aimed to protect large game animals from their natural predators, such as wolves.
Once the ranching industry made it to the Rocky Mountains, state and federal governments alike paid people to kill wolves through the employment of bounties and programs designed for poisoning wolves (Blakeslee, p. 104). As a result, wolves had been effectively removed from the majority of the lower 48 states by the early twentieth century. Shortly after the extermination of wolves in the United States, the ungulate (elk, deer, etc) populations in the park exploded and rangers were instructed to cull the herds in order to protect vegetation. Then, just a few decades later, the US Fish and Wildlife Service decided to add wolves to the endangered species list and to begin reintroducing them to the park.
In the twenty-two years since the reintroduction, the government has simultaneously tried to keep populations of wolves healthy and also allow extensive hunting of wolves. This saga of the Yellowstone Wolves perfectly showcases the back-and-forth arguments that saturate wildlife management issues. These situations are multi-faceted at best; some of the voices involved include state governments, federal agencies, ecologists, biologists, animal activists, ranchers, and hunters.
Although wildlife management issues are complicated enough as they are, cases like the Yellowstone wolves present questions about how we conceptualize wildlife. The reversal of the government's stance on wolves in the United States shows that our ideas about what is good and beneficial to the environment-and to humans-can change drastically over time. For example, few people would consider wolves to be an invasive species and, because of the ambiguity of what it means to be an invasive species, we can see that our terminology and concepts of wildlife and natural systems are problematic.
Wolves and Trophic Cascade
When wolves are discussed in the context of their ecological impact, they are usually attributed to causing a trophic cascade, which is often regarded as a positive thing. Trophic cascades, "occur when the presence of a top predator substantially affects consumer (herbivore) behavior or population size, thereby influencing producer (plant) abundance, structure, or spatial distribution" (Ripple et al, 31). In Yellowstone, the return of wolves to the landscape reduced elk populations, which caused an increase in aspens, cottonwoods, and willows: plant species that were nearly decimated by elk grazing (Ripple & Beschta, 1). Wolf presence in the park has also caused a decline in Yellowstone coyote populations and a rise in red fox, beaver, raven, and eagle populations (Lambert, 20 Mar. 2018).
The landscape of Yellowstone National Park is entirely different from what it was before the wolf reintroduction, which means that the wolves have had a profound effect on the ecosystem. This much may seem obvious, but what is less evident is their status as a potential invasive species. What does it mean to be a 'native' species or to be an 'alien' species? How long does a species have to be absent from an ecosystem in order for it to lose its 'native species' title? Wolves were absent from the Yellowstone ecosystem for 70 years, and their absence dramatically changed the landscape; coyotes became the top canine predator and elk began to thrive.
Conversely, when wolves returned, they had a negative effect on coyotes and elk. As mentioned earlier, the National Wildlife Federation (NWF) outlined that an invasive species is one that is non-native and has detrimental effects on members of an ecosystem. In this way, wolves can certainly be categorized as an invasive species if we can concede that an absence of 70 years would cause wolves to lose their status as a native species of Yellowstone.
Ecology & Conservation
There are some ecological and conservationist implications of wolves as an invasive species in Yellowstone. Ecologists, biologists, and other conservationists in Yellowstone would inherently have to view wolves as a non-invasive species in order to justify their protection under the Endangered Species Act. If wolves were viewed as an invasive species, they never would have been released into Yellowstone.
What becomes clear is that the issue of invasive species has very little to do with the animals themselves and more to do with how ecologists and biologists view the species in question. Moreover, animals worthy of conservation and protection are also considered based on human interests and not the interests of the animals. If in one part of a century we can view wolves as pests to be exterminated and during another part of that same century we can view wolves as majestic keystone species to protect, what does this say about human relations to wildlife management?
Firstly, it communicates that these issues are ecologically and politically motivated. Animals have become commodities and they are discussed in terms of money. When the wolves of Yellowstone expand beyond the park borders, they can be hunted (Blakeslee, 67); state wildlife agencies collect the money from hunting licenses. When the wolves of Yellowstone kill livestock, the ranchers must be paid damages by state wildlife agencies. When the wolves of Yellowstone hunt elk, they change elk behavior, which makes them harder for humans to hunt, which in turn damages the economies of some of the smaller towns around Yellowstone (Blakeslee, 77).
Furthermore, it costs money to do research on these animals; everything from biologist salaries to equipment and food must be paid for. Although wolves have been reintroduced to Yellowstone and continue to be studied as part of a conservation effort on the part of biologists and federal wildlife agencies, they are still viewed in terms of money and property.
Wolves & Animal Rights Theory
There are also many animal rights implications of the wolf situation in Yellowstone. Animal activists tend not to bother with terms like 'endangered' and 'invasive.' However, they do tend to put their efforts into speaking out in favor of controversial animals. Regardless of where activists fall on the spectrum of animal ethics, they tend to care more about red wolves (Canis rufus) rather than the endangered alligator snapping turtle (Macrochelys temminckii)-for example.
The attention that beautiful, cute, or controversial species receive is perhaps indicative of how we view animals. Are there some animals unworthy of our attention? Perhaps we do not see it in those terms necessarily, but there does seem to be some indication that animal activists only emerge when there is latent conflict in a wildlife management situation. Animal activists seem to be on the side of animal rights theory (like PETA) which means that they wish to place animals on the side of humans in the 'person-thing' binary (Francione, 187).
What is unfortunate-and frustrating-for animal rights activists is that animals are still largely considered to be property, and therefore things, rather than individuals with their own interests. Although the reintroduction of wolves into Yellowstone is often praised as the greatest conservation success story of all time, the interests of the wolves were not taken into consideration. Perhaps the wolves did not want to be moved; they most certainly did not wish to be killed when they ventured out of the park.
Additionally, gray wolves have been de-listed in the areas of the United States where they exist, but they are protected under the Endangered Species Act in places where they do not exist (Lambert, 13 Mar. 2018). The highest populations of wolves in the lower 48 states exist in Idaho, Montana, and Wyoming and these are the states in which they are no longer protected under the Endangered Species Act (ESA.) However, in states like Illinois or Kansas, wolves are protected under the ESA; these are states where there are no wolf populations. I fail to see how this makes any sense at all.
These kinds of political constructs have power over the lives of other sentient beings and these kinds of nonsensical decisions continue to fuel the conflict among the voices involved in wildlife conservation and management.
Furthermore, it is important to consider some of the problematic elements of animal rights theory. According to this theory, animal rights activists want all animals to be treated as though they have their own interests; they believe that animals should be left to do as they please and that we humans should not kill them regardless of what is at stake. I have to wonder, however, what happens when the interests of the animals interfere with human interests?
What would animal rights activists have to say of a predatory mammal taking a human life? In May 2018, a five-year-old girl was attacked by a black bear (Ursus americanus) in Colorado and the bear was later hunted down and killed by Colorado Parks and Wildlife because the bear posed a threat to human life. In such a case, how can animal rights activists justify their plea to keep the bear alive when it would almost certainly go on to kill someone in the future?
Cases of problem animals are complicated, to say the least. If a predatory animal becomes an issue for people, there are ways to discourage the undesired behavior that can threaten human life. According to U.S. National Park Service, "eight wolves in Yellowstone National Park have become habituated to humans. Biologists successfully conducted aversive conditioning on some of them to discourage being close to humans, but two have had to be killed" (Wolves, 7). Presumably these two wolves 'had to be killed' because they were a threat to human safety. Would animal rights activists still believe in a hands-off approach if a wolf killed a child?
Perhaps there is a way to develop a balanced approach to living with wildlife without treating them as commodities or allowing them to behave violently towards people. However, as long as there are differing views on how best to manage human-wildlife interactions, there will continue to be a back-and-forth approach to conceptualizing the role that animals play in the world.
Where to Go From Here
As the wolf story in the US demonstrates, wildlife management is hardly a cut-and-dry issue. We cannot separate ourselves from nature and wildlife, but does that make it our 'job' to meddle in the affairs of wildlife? It seems unjust that a social construct like the U.S. Fish and Wildlife Service controls the lives of animals and that they can reverse their roles over the course of a few decades.
Moreover, as Nate Blakeslee poignantly addresses in his book American Wolf, "Research in Yellowstone had strongly suggested that unexploited wolf populations, left to their own devices, would eventually level off on their own, without culling of any kind" (130).
Perhaps the animal activists are on the right track with their hands-off approach; it may take another few years for animal ethics to evolve into something that would allow for humans to stop meddling in the lives of animals unless an animal presented a threat to human life. That being said, what would stop wolf-haters-for instance-from hunting down every wolf they could find, if the government chose not to get involved?
The questions I have raised in this discussion point precisely to why animals and nature are so controversial; people cannot agree about how to interact with the world that surrounds us and how to coexist with non-human animals. Hopefully with some baby steps, we can start to move towards a common ground-before time runs out for the wolves and other such species.
Sources
1. "Bear killed after attack in Colorado leaves girl with more than 70 stitches." FoxNews.com. Fox News. 14 May 2018. Web.
2. Blakeslee, Nate. American Wolf: A True Story of Survival and Obsession in the West. New York: Crown, 2017. Print.
3. Francione, Gary. "A Review of Beyond Animal Rights: A Feminist Caring Ethic for the Treatment of Animals." Women's Rights Law Reporter (1996) 18, 95-106. Web.
4. "Invasive Species." NWF.org. The National Wildlife Federation. n.d. Web. 25 Apr. 2018.
5. Lambert, Joanna. Class lectures, Anthropology 2005: Dogs, Wolves & Human Evolution. Spring 2018 Semester.
6. Ripple, William and Robert Beschta. "Trophic cascades in Yellowstone: The first 15 years after wolf reintroduction." Biological Conservation (2011) 10.1016, 1-9. Web.
7. Ripple, William et al. "Wolves, Elk, Bison, and Secondary Trophic Cascades in Yellowstone National Park." The Open Ecology Journal (2010) 3, 31-37. Web.
8. "Wolves." NPS.gov. Yellowstone National Park (U.S. National Park Service.) 13 Jun. 2017. Web. 25 Apr. 2018.