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For years ranchers have argued that wolves should have never been reintroduced to the Yellowstone area of Wyoming.  The wolves, at a population of only 21, were reintroduced into the area in 1995.  At that time there were 17,000 Elk in the area.  Since then, the total Elk population has decreased to 4,844 in 2015.  On the other hand, the wolf population has increased to 99 in 2015.  As the population of the Elk have decreased, the population of the wolves have increased.  Many people associate the wolves as the major cause for the Elk population decreasing.  However, this may not be the case, as there are many other factors that may be causing the Elk population to decrease. From 1989 to 2009, it was determined that the number of calves surviving to adulthood had declined a staggering 74 percent.  Wildlife biologist Shannon Barber-Meyer followed 151 Elk calves in Yellowstone for 3 years and determined that 70 percent of these calves died before their first birthday. Every year up to  2/3 of calves are victims of predators. Calves are a source of food for many hunters including: black and grizzly bears, wolves, coyotes, cougars, and golden eagles.  Of those calves killed by predators, it was determined that only 15 percent of these calves were killed by wolves.  Even with a wolf’s diet in the winter being between 1/2 calves and 1/4 bull elk or vice versa, wolves still only accounted for 15% of all elk deaths, while bear made up 60% of kills (More than half being Grizzlies).  The number of bears preying on the Elk has grown over 3 times in the past 20 years.  In the past, Grizzlies have been known to rely heavily on cutthroat trout as their main source of food.  But since the 1980’s this began to decrease because lake trout was illegally released into the Yellowstone Lake.  The newly introduced trout preyed on and competed with the native trout for resources reducing the population of the native trout.  On top of that the new trout also lived in the deeper waters more often than the native trout, making them harder for the Grizzlies to feed on.  Because of this the Grizzlies had to look at alternative sources for food, with Elk calves being an easy next target.  Another factor that has affected the elk population in Yellowstone dramatically is climate. Climate influences size and distribution of elk herds. Elks are classified as ungulates which migrate to gain accessibility to high-quality food. This is due to their preference of more nutritious young plants. In the winter, cold temperatures and snowfall greatly decrease forage growth and accessibility. This results in elks migrating out of Yellowstone to find more quality food. Migrating ungulates have the tendency to give birth during periods of peak vegetation growth. Elk mothers and calves require nutritious food to build up essential fat reserves. Depending on a given year’s climate, newborn elk can experience positive or negative effects. The best outcome for a newborn calf is being born in a year with an early spring. An early spring tends to lead to longer seasons without snow. This ensures that migratory patterns and food accessibility is not restricted. On the other hand, longer seasons of plant growth lacking nutritious forage can have a serious negative impact of calves. Plants can complete their growth cycles significantly faster in warmer temperatures. While this may be a benefit for the plants, an increase growth cycle results in a shorten timeframe for quality food and accessibility for elk. These early springs can cause mistiming between the birth of calves and peak plant nutrition. Unfortunately, this will result in a high mortality rate among newborn calves. Climate plays a vital role in the lives of newborn calves, and slight changes in weather have a direct impact on a calf’s’ chance of survival.Another natural event that has affected elk population is the exposure of chemicals and diseases.  Grazing elks near geysers and hot pools in Yellowstone have been shown to die up to five years earlier than elk found in other areas of the park. This is due to elevated levels of fluoride and silica in water. Elk have begun grazing near the Madison-Firehole area. This is an area full of geysers, hot pools, and mud pots. Fluoride, magma, and silica dust found in soil next to water have been destroying elks’ teeth. The decay of their teeth leads to an inability to chew food. This means that the elk cannot break down plant tissues. As a result, elk cannot release trapped plant nutrients.  When it comes to diseases, Elk are greatly affected by multiple types, such as Brucellosis and Chronic wasting disease. Brucellosis is a contagious bacterial disease that causes infected elks, cattle and bison to abort their first calves. Chronic wasting disease is a neurological disease that causes brain degeneration and it can lead to emaciation, unusual behavior, loss of bodily functions and death.  Overall, the combination of elks grazing near hot springs and exposing themselves to various harmful chemicals, as well as the spread of diseases that are fatal to them, has led to the population to decrease.       To play devil’s advocate with those using the argument that wolves should never have been introduced I will consider that exact thing, what if wolves were never reintroduced? There is a plethora of possible events that would result from this scenario. Imagine the Elk population thriving immensely, so much that they start to have over populating problems. Food shortages start to occur, not just for Elk but all other animals who share a common diet. In a certain aspect the wolves kept this ecosystem in balance, not allowing one species to increase in population in a manner that could affect the others. The Elks were a main cause for decline of another population; for example, the beavers. Also, many researchers determined that wolves were beneficial to the ecosystem due to the fact they kept the Elk on the move. Beavers need willow stands to survive in the winter and with the Elk grazing the same areas where willow was found along the streams, beavers were in bad shape. However today with more Elk the willow stands are in great shape simply due to the fact the wolves keep the elk moving around the area and not settling in on one spot for extended periods of time. In an environment like Yellowstone, it is very complex and there is not just one variable to blame. To go along with that this data has been shown in possibly a manipulative manner. We can see the elk went down by a large margin from 1995-2003 but that doesn’t necessarily have anything to do with the wolves. As with any predatory species put in an environment where they have enough food they will most certainly grow and reproduce quickly. And during the drop-off of 2003-2012, wolves had more of a decline. Which suggests possibilities like climate changes, food shortage, diseases, rather than simple predatory killings. And both seem to be on an increase of population lately which seems to go against the argument of more wolves being not just a nuisance, but a menace. To go along with some of these glaring instances, we are also using a random and inconsistent time frame between data collections, which raises suspicion. Maybe the big bad wolves are not so bad after all.

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