Savvy honors researcher devises methods to monitor an invasive water plant

Katherine “Katie” Ferguson is a biology major and chemistry minor on the pre-vet track at Sweet Briar College. The rising senior from Hampstead, N.C., spent eight weeks from May to July in the Honors Summer Research Program working full time on mapping the distribution and density of hydrilla, an invasive water plant, in the College’s Lower Lake. Her project is titled “A Study on the Chemical and Physical Effects of Hydrilla verticillata and How to Monitor It.”

Ferguson collected her data using a drone for aerial photography and a grid system from a canoe on the water to conduct a “presence/absence” survey. She also modified a five-gallon bucket to construct a tool to take biomass samples of the hydrilla to track the plant’s density around the lake.

The goal of her research was to establish and document effective survey methods so the Sweet Briar biology department has a way to monitor changes in the hydrilla distribution and density over time.

Ferguson was often in uncharted territory, from inventing her own sampler to teaching herself to fly the drone. She was fearless, say Dorys McConnell Duberg Professor of Ecology Linda Fink, who served as her faculty advisor on the project.

“Katie is willing to try everything, she figures out the techniques, she goes into the literature, she is fantastic at troubleshooting and problem-solving,” Fink said.

Ferguson became interested in the topic because her job as an instructor in the Sweet Briar Outdoor Program meant she was on the lake a lot. She could see the hydrilla was impacting recreational activities. When she learned the College was introducing sterile grass carp in an effort to control the plant, the idea to measure the fish’s effectiveness was born.

“As a biology major, I understand that invasive species have the potential to put a major strain on the ecosystems they inhabit,” she says.

“There is usually not a cut-and-dry solution because of the diverse factors involved, but the first step is quantifying the problem. As a pre-vet student, working towards the solution to problems that aren’t black and white will be an invaluable experience and provide me with irreplaceable skills for my future.”