Reintroduction and Reproduction of Wolves in Yellowstone

Opponents of reintroduction frequently claim that putting wolves back into the wild will result in innocent humans being attacked or even killed by said wolves. This perception is tied to sociocultural influences causing fear of predatory animals, along with simple lack of education. For example, we all know the story of the three little pigs, in which the wolf is the antagonist. Likewise, in “Little Red Riding Hood,” the wolf tries to sneakily eat the innocent little girl. In reality, though, attacks on humans are extremely rare. There have been no attacks on humans since Yellowstone’s program began (Evan). No one has even been so much as bitten by a wolf in the 21 years since reintroduction began (Milman). In fact, there have only been two documented attacks in North America since 1995, and neither attack was fatal; one was in Minnesota in 1996, and the other in Ontario in 2013 (Milman). Clearly, the view that wolves are cold-blooded killing machines is unfounded.

There is some merit to concern about wolves coming into close contact with humans, but not for the reasons one might think. Wildlife officials are currently monitoring a situation in Cooke City, Montana, where wolves have been exhibiting signs of habituation (Somerby). Habituation means that wolves are too close for comfort, and it can be a sign that wildlife has become too reliant on human resources, such as Dumpsters, for food. However, this is markedly different from wolves targeting and killing humans for sport and eating them. In fact, one could easily make the argument that humans are more dangerous to wolves than wolves are to humans.

Similarly, ranchers often decry reintroduction as the precursor to the unraveling of their livelihoods. One farmer claimed to have lost 300 sheep in a year due to a nearby wolf pack; however, once state officials investigated, only 24 kills were confirmed (Povich). Wolves do attack livestock, but not in the numbers that opponents advertise. Additionally, there are programs in place to compensate ranchers for lost livestock, although compensation can sometimes be significantly less than market price (Povich). Obviously, this is upsetting to people whose livelihood depends on how much money they can get from each animal. Flaws in the compensation systems need to be addressed.

Another factor to consider is that wolves have effects on livestock beyond just life and death; one lifelong rancher, Len McIrvin, said that his animals are unsettled and their calving rates have declined because of nearby wolves (Povich). While these effects are hard to measure, and therefore there’s not much data to investigate them, they are still worthy of consideration when discussing the effects of wolf reintroduction. When compared with deaths from other predators or natural causes, though, wolves account for a miniscule number of livestock deaths (Povich). Therefore, changes in livestock behavior and reproduction numbers may be due to other predators, and not just because of wolves. It might be easy and logical to make wolves into a scapegoat, but to do so would be misinformed.

While wolves are mostly protected, laws do allow them to be killed in certain situations. In Montana, if a wolf is deemed to be a threat to humans, dogs, or livestock, they can be killed on private land; if they are in the act of attacking, they can be killed on public land as well (Somerby). These laws are obviously in place to protect humans and their interests from physical harm. Additionally, wolf hunts, seasons, and quotas have been established in some states in an effort to prevent their population from becoming too large (Gannon). As of 2015, there were about 1900 wolves across five western states (Povich); in Wyoming’s last legal wolf hunting season, 23 wolves were legally killed (Gruver). Wolf hunts are a viable option to help prevent conflicts with human interests as long as the quotas continue to be low enough to prevent them from being eradicated again.

For ranchers concerned about nearby wolf packs, there are a host of non-lethal deterrents and strategies available. GPS tracking of wolves can provide valuable insight on where livestock should graze; by avoiding high-risk areas, farmers can reduce the risk that they lose their animals to wolves (Evan). Fladry barriers, which are fences made of a single string with brightly-colored strips of fabric hanging down from the string, have been extremely effective in preventing wolf attacks; furthermore, they are relatively cheap, especially compared to other deterrents (Stone 12). Electric fences and electrified fladry barriers (called turbofladry) have been shown to be even more effective than regular fladry, and solar charging options are available to reduce cost to the rancher (Stone 13). The size of one’s herd and grazing area will also dictate which methods are best to deter wolves. Fladry barriers and portable fencing are good options for large grazing areas and open pastures (Stone 13), but permanent fencing is better for small herds (Stone 12). “Scare devices” like air horns, starter pistols, and non-lethal ammunition are proven to deter wolves, but a rancher would have to know the wolf is there to use them, making them less convenient and reliable (Stone 15). Livestock guard dogs are also a popular option, but it’s important to note that these dogs are different than herding dogs, and they serve a very different purpose --- you can’t just throw your sheepdog out in the pasture and expect them to keep the wolves away (Stone 8). There are a host of other options available, with wildlife officials and conservation groups working constantly to improve and invent new strategies to deter wolves. The evidence clearly shows that non-lethal deterrents can be effective in protecting livestock. Wolves and ranchers can coexist.

The coexistence of wolves and humans is not only possible, but necessary to maintain the ecosystem. Without wolves, the ecosystem unravels, as was demonstrated in Yellowstone --- elk populations boomed without wolves to keep them in check, and the elk overgrazed the land (Cornwall). While all types of vegetation were affected, willows and aspen were especially affected (Lackey). Beavers left because they had no food and no way to build dams, and the lack of dams caused rivers to both erode and dry up (Cornwall). The lack of beavers further complicated the plight of willows --- they are water-loving trees, and the growth of those that were left was severely stunted by the changes in waterways (Kuhne). The loss of vegetation in general caused small mammal populations to be decimated because the other predators had less competition, while birds lost cover and resources for nesting (Evan). The Yellowstone ecosystem was drastically and dangerously imbalanced without wolves.

The main benefit of wolf reintroduction is the domino effect they have on their ecosystem. Since they are apex predators, returning them to the environment will result in changes across the entire food system. This domino effect is referred to by scientists as trophic cascades. The trophic cascade expected to occur in Yellowstone was that the wolves would help control the elk population, allowing vegetation and forests to recover (Kuhne). The reintroduction of wolves did, in fact, correlate with a positive uptick in willow, aspen, beaver, small mammal and bird populations (Lackey). A 2012 study on wolves, coyotes and rodents in neighboring Grand Teton National Park seemed to support the trophic cascades theory. It found that coyotes stayed away from wolf dens and went farther and farther away as time went on; at the same time, rodent populations near the dens increased but remained stable elsewhere, suggesting that “restoration of wolves could be a powerful tool for regulating predation at lower trophic levels” (Miller, et al). Elk pregnancy rates declined after wolves were brought back, which also indicates the wolves’ role in containing elk populations (French). As shown by the Yellowstone project, reintroducing wolves has a clear benefit on the rest of the ecosystem.

Despite these positive consequences, concerns remain about the extent of the damage that was done to the ecosystem without wolves. Many experts believe the Yellowstone ecosystem was damaged beyond repair by removing wolves. Ecologist David Cooper warns that “some sites may never recover,” as the damage done to streams may never be reversed (Cornwall). Likewise, Bill Ripple, an Oregon State University professor, believes the main lesson to be learned from Yellowstone is “Don’t let things get [that] bad” (Lackey). There are concerns over the limitations of the data, too. The food web in Yellowstone is complex and multifactorial, affected by things like weather and human activity (Kuhne). Additionally, the lack of resources and funding make it difficult to collect enough data and to study all of the factors (Lackey). Despite these concerns, it’s safe to say that reintroducing wolves to Yellowstone has had a net benefit to the park and the ecosystem. The reintroduction of wolves to Yellowstone serves both as an important reminder to prevent these environmental losses from happening again, and as a beacon of hope for the future of conservation.