Students in Viterbo University’s conservation biology course spent the beautiful afternoon of Oct. 17 conducting a study of the population of brown trout in Timber Coulee Creek near Coon Valley.
“One of the goals of conservation biology is to understand environmental conditions including the population size and distribution of plants and animals,” said Viterbo faculty member Michael Alfieri, Ph.D., who teaches the course. “This particular lab is designed to have students use a sampling method for estimating population size and determining the distribution of organisms.”
For this study, students used a backpack electrofisher to capture and mark the brown trout in a 200-meter segment of the creek. A week later, the creek is sampled again to determine the ratio of marked to unmarked fish of this species. This is known as the mark-recapture or Lincoln-Peterson method, Alfieri explained. The idea is that if the population is large, then marked individuals will have become “diluted” in the population, but if the population is relatively small then more previously marked animals would be in the second sample. The total population may be estimated through relatively simple equations.
“The students then use the data they collected to write lab reports in which they estimate population sizes, determine the average length of trout captured in the creek, and statistically compare these findings among years,” Alfieri said. “As this is a scientific research project, each year we submit for a scientific collectors permit from the Wisconsin Department of Natural Resources. The DNR is given access to our data as part of our work. I have sampled this creek with students for the past 12 years, so we can provide long-term data about populations and fish sizes from small creeks.”
This was just one of many field experiences students undertake in the course. Others include touring Holland Sand Prairie to learn plant and animal identification and conservation practices, conducting aquatic invasive species detection with the River Alliance of Wisconsin, learning about sustainable and organic fruit and animal production on a small family farm at Hoch Orchard and Gardens, and discovering career options and talking with researchers in conservation efforts at the Genoa National Fish Hatchery, USGS Upper Midwest Environmental Science Center, and U.S. Fish and Wildlife La Crosse Fish Health Center.
“Students are gaining valuable field experiences by conducting activities commonly used by professionals,” said Alfieri. “This course is especially focused on the laboratory activities, conducting research, applying theory learned in class, and visiting and discussing conservation issues with local persons practicing and working in the field of conservation biology. It is about working with and learning from members of our community.”
The course is popular with students, including Erin Heiting. She is majoring in environmental biology and is very interested in a career in the field.
“I definitely have enjoyed my experience in this course,” Heiting said. “It covers many important topics, and we are able to learn even more about those subjects in the field. What other class lets you set up cameras in the woods, canoe the backwaters of the Mississippi, and catch brown trout in a stream? This class has certainly made me more aware of conservation issues, both global and local.”
Environmental biology major Paxton Smith would like a career with the U.S. Fish and Wildlife Service or the DNR.
“This class lets us take what we learn in the classroom and apply it directly in the field,” Smith said. “In addition, hearing from different conservation biologists about their specialties is great because we are able to learn from professionals with different perspectives.”