Prairie Ecology Section One

Post by 2016 Montana Summer Program student Caroline Guerry

From the moment I stepped off of the plane I quickly realized that I was definitely not in South Carolina anymore. As we drove away from the airport to Roundup we passed miles and miles of farm land, ranch land, and open prairie. I was completely captivated by the vast amounts of space that were suddenly in front of me. I had never been in a place where you could see everything for acres on end. After unloading our belongings at the High Meadows Ranch, we were invited to the Segar’s home and were welcomed with kindness and hospitality.

               The next morning it was time to venture into the Great Plains to the American Prairie Reserve where we would be camping for the next few days while studying the species and the ecology of the prairie. On our way to the campground we stopped at a bridge that went over a stream where a Great Horned Owl nest was. We saw the owl fly out and into a massive cottonwood tree. Here, we were able to see one of the ways that cattle affect wildlife, which is through water contamination.  Since cows tend to stand in water while they drink, the water can then become contaminated with sediment and fecal matter from the cows, which then causes an increase in algae, and in turn a decrease in amphibian species that once inhabited the stream. The same contaminates cause the soil to be less fertile, which makes the mature cottonwoods surrounding the stream to begin to die and inhibiting their seedling from growing. It was difficult to think about all of the negative impacts that cattle can have on an ecosystem like this one. Since I had been around cows my entire life I expected to know about more about them and how their habits can affect their surrounding, however I have since learned that is not the case. I have only just begun to understand how problematic cattle can be to the Great Plains.

               The next day of our camping adventure was spent on the American Prairie Reserve where we drove around the property in search of its great diversity of wildlife and vegetation. As we rode through the heat and clouds of mosquitoes we saw Mule Deer, Pronghorn, Bison, Prairie Dogs, and more species of birds than I could ever count. Throughout our day Dr. McMillan and his son Nic taught us about the different habitats within the prairie. From afar, one would think that the same species would be found throughout the entire area. We soon learned that this is not the case. Some species that are found in the Great Plains can only be found in certain vegetation. For example, a Brewer’s Sparrow requires shorter species of grass along with sagebrush cover. However the Grasshopper Sparrow requires taller species of grass along with sagebrush cover. These two different habitats can be found within a few yards of each other and most would not be able to detect the slight change. In the Southeast it can be much easier to see the changes in habitat, but on the plains there can be a complete change in habitat and species with the addition or loss of a single species of vegetation. Such a subtle change can make such a big difference.

               The next day was one of my favorites of this section. We began with a visit to a Prairie Dog town where we studied their behaviors, as well as some of the problems that they are facing as a species. When we first pulled up to the Prairie Dog town, the individuals that were closest to us began to make a high-pitched chirping call while they were crouched and flicked their tail up and down. This is their alarm call so that the Prairie Dogs with a higher social standing that live in the center of the town know there is a potential predator. A town is organized into coteries which contain a single family and my include extended family. The families that are the strongest and most genetically successful are ranked highest in the town’s social order and occupy the burrows in the center of the town. The burrows that the Prairie Dogs make are extremely complex and have given them the title of ecosystem engineers. The burrows that they make turn over the soil and they constantly trim the grass so that they can see over it when scouting for predators. The Prairie Dog population today is in danger of extinction for two main reasons. The first is that a landowner has the right to poison Prairie Dogs on their property. Most choose to do so because they think that their cattle will have to compete for grass. By using poisons such as Rozol and Zinc Phosphide, a landowner can efficiently exterminate a Prairie Dog town. However, when another organism such as a hawk or coyote eats a poisoned Prairie Dog, the chemicals are then transferred to that organism causing it to potentially die. Another danger to the Prairie Dog population is the sylvatic plague. This disease is the same as the bubonic plague; the only difference is that it occurs in animals as opposed to humans. Similar to bubonic plague, the sylvatic plague is initially given to the Prairie Dogs by fleas and quickly spreads throughout a town. The plague is currently being somewhat controlled by the US Fish and Wildlife Service who spray Prairie Dog burrows with flea powder that kills the fleas. Prairie Dogs can be beneficial to the Great Plains and I can understand how some locals may not understand that. The grass on Prairie Dog towns is much higher quality than that which is not on a town. They may see the Prairie Dogs as a competitor, when in reality they have a positive impact on the ecosystem around them. I’ve come to realize that this controversial topic and many others might stem from a lack of understanding from both sides. Locals may not understand the biological reasons why Prairie Dogs can benefit them, and biologist and the people of the American Prairie Reserve might no understand the ways of the ranchers and their thought behind their actions.

               On our last full day at the American Prairie Reserve, we traveled to the small town of Malta where we visited the US Department of Agriculture office and the Bowdoin National Wildlife Refuge. In the center of refuge is a natural salt-water lake where thousands of shore birds and waterfowl come to in order to nest in the spring and early summer. I would have never expected to see such a large amount of sea birds in a place so far from the ocean. We learned that many White Pelicans nest here because of one small island in the middle of the lake. If the Pelicans’ are disturbed they will completely abandon their nest and young chicks, so the island gives them a sense of isolation.

               Over the past six days my eyes have been opened to an entire new world. I’ve learned so much about the Great Plains as well as wildlife in general. The experiences that I’ve had allow me to picture myself working in this field now more than ever. This past week has been one of the best of my life and I cannot wait to see what the future holds.