Wolf Reintroduction: Good for Yellowstone Ecosystem


By: Heather Jenks
Wichita, Kansas
12/2004

Since humans first drew petroglyphs to record their observations, wolves have populated the art, literature and culture of our planet. The howl of the wolf sends shivers of fascination and love, or fear and distrust, up the backs of people around the world. Hardly anyone treats the wolf with indifference. (Steinhart)

Wolves are the largest members of the canid family. This is the species from which our pet dogs were domesticated. Wolves were once the most widely distributed wild mammals. They inhabited most of the available land in the northern hemisphere. Due to the destruction of their habitat and persecution by humans, they now occupy only about two-thirds of their former range worldwide, and only about 3 percent of the continental 48 United States. (International Wolf Center) Contrary to popular belief, wolves are not the fierce destructive killers that people make them out to be. Childhood stories such as “The Little Red Riding Hood” reflect the haunting fear of wolves as vicious and efficient killers.

Recently the reintroduction of wolves to Yellowstone National Park was a huge concern to people of that region for that very reason. However the reintroduction of Gray Wolves into Yellowstone has had many positive affects to the environment and fragile ecosystem. What exactly constitutes the environment and ecosystem? Environment is defined as: “The aggregate of surrounding things or conditions; the totality of external influences on an organism.?? (Webster Dictionary) The environment that I researched was Yellowstone National Park and how the balance of the parks ecosystem was interrupted because of fear and paranoia. Ecosystem is defined as: “An ecological community.?? (M-W Online Dictionary)

Wolves were wiped out from at least 95% of their historic range in the United States over a period of more than 100 years. (Steinhart) Our European ancestors brought with them an unreasonable fear and paranoia, which manifested itself in ways, that were harmful to the wolf, and indeed, to the very ecosystem of this continent. The need for domestic livestock, the fear of predators, the need to assert our dominance over animals, the word of God, prejudice, and downright maliciousness were all reasons that our ancestors felt were compelling enough to take the life of one of nature””””s balancing forces. Research published in November 2003 revealed that—unlike other top predators—Yellowstone””””s wolves routinely leave unfinished elk and moose carcasses. Which provide essential scraps for scavenging coyotes, eagles, and other animals. Related work suggests that these carcasses provide dinner more consistently, and for more species, than remains discarded by human hunters. (Pickerell) This leads me to the reintroduction program at Yellowstone National Park. Reintroduction is the act of bringing individuals of a certain species (plant or animal) back into a designated area within the species”””” original range, but from which it was extirpated or nearly eliminated. The purpose of reintroduction is to establish a new population in the wild. In the case of the wolf we were trying to move away from the total extinction of a species in the wild.

Northern Rocky Mountain wolves, a subspecies of the gray wolf, were native to Yellowstone when the park was established in 1872. Predator control was practiced here in the late 1800s and early 1900s. Between 1914 and 1926, at least 136 wolves were killed in the park; by the 1940s, wolf packs were rarely reported. By the 1970s, scientists found no evidence of a wolf population in Yellowstone. An occasional wolf likely wandered into the Yellowstone area; however, no verifiable evidence of a breeding pair of wolves existed through the mid 1990s. In the early 1980s, wolves began to reestablish themselves near Glacier National Park in northern Montana; an estimated 75 wolves inhabited Montana in 1996.

The U.S. Fish & Wildlife Service 1987 Northern Rocky Mountain Wolf Recovery Plan proposed reintroduction of an “experimental population” of wolves into Yellowstone. In a report to Congress, scientists from the University of Wyoming predicted reductions of elk (15%-25%), bison (5%-15%), moose, and mule deer could result from wolf restoration in Yellowstone. A separate panel of 15 experts predicted decreases in moose (10%-15%) and mule deer (20%-30%). Minor effects were predicted for grizzly bears and mountain lions. Coyotes probably would decline and red foxes probably would increase. (Mech)

One of the most important changes expected from the reintroduction of wolves to Yellowstone National Park was the recovery of certain tree species. Young cottonwoods, aspens and other streamside woody species are the preferred food for browsing elk during the harsh winters in northern Yellowstone, when much of the other forage is buried under snow. But when packs of wolves historically roamed the area, food was not the only consideration for elk, which had to be very careful and apparently avoided browsing in high-risk areas with low visibility or escape barriers.

In 1997, William Ripple, Oregon State University forest ecologist, set out to unravel the mystery of the disappearing aspen in Yellowstone National Park (YNP).“We had several theories on the cause of the decline,?? Ripple said in an interview from his Corvallis, Ore., office. “It could be caused by the lack of fire, climate change, or other environmental factors. We weren’t sure.?? Ripple discovered the aspen quit regenerating in the 1920s.

For 70 years, young aspen hadn’t faired well, with few surviving to become mature trees. About the same time that the aspen quit regenerating, wolves were eliminated from the park. Ripple said the timing begged the question: Is there a connection? “We developed the hypothesis that there was some link among wolves, elk and aspen,?? Ripple said. (Travsky)

With the absence of wolves the elk were able to graze anywhere they wanted without fearing that a predator was close by. I do feel that the removal of wolves caused the park trees to stop regenerating. In fact, it began to play havoc with an entire streamside ecosystem and associated wildlife, including birds, insects, fish and others. Trees and shrubs were lost that could have helped control stream erosion. Before the wolves came back, it was pretty clear that in some areas we were heading towards an outright extinction of cottonwoods. (Beschta)

Consider the northern Yellowstone elk herd, which has declined for the past several years. The recovery of the wolf has occurred simultaneously with increases in grizzly bear and mountain lion populations, increased human hunting of elk north of the park, and an extended drought. The elk populations of Yellowstone will no doubt continue to adjust to all the pressures and opportunities they face, just as all their wild neighbors, large and small, will. (Schullery)

Now that the wolves have been reintroduced shrubbery has begun to grow near the water again giving the trout that swim in the streams shade. The nearly 300 wolves at YNP have brought balance to the park and in my opinion we should have never played with the balance of nature. Although the reintroduction of wolves still remains controversial, the once endangered species has begun its journey to becoming delisted and the aspen and cottonwoods of YNP have begun to flourish once more.

I still believe that messing with nature is wrong and that we should have never played ‘God’ by removing wolves from the wild. Thanks to a controversial but very successful reintroduction program, wolves are now back in Yellowstone after an absence of almost 70 years. I think that because wolves hunt elk, willow trees are recovering in the park. I also believe that more species are thriving because the wolf was placed back where it belongs. For example many animals that may have had a hard time getting food in the winter can feed off of the carcass from a pack’s kill. It is a giant chain reaction and wolves are vital part of that chain.

Works Cited

Beschta, Robert. Wolves Are Rebalancing Yellowstone Ecosystem.
Environment and Ecosystem.Merriam-Webster Dictionary. 2004
International Wolf Center. www.wolf.org
Mech, L. David. “The Challenge and Opportunity of Recovering Wolf Populations.Conservation Biology 1995 9(2) pgs. 1-9
Pickerell, John “Wolves Leftovers Are Yellowstone’s Gain, Study Says National Geographic News 4 December 2003
Schullery, Paul. The complexity of Yellowstone’s wild community.
Steinhart, Peter. The Company of Wolves. New York 1995
Travsky, Amber. “Wolves linked to vegetation improvements. Wyoming Tribune-Eagle newspaper. March 18, 2004.

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