Feral Cats: Computational Study Looks at How Best to Fix the Nuisance

Working with faculty members in mathematics and biology, a Duquesne undergraduate majoring in computer science and mathematics, as well as physics, has created the first computational model to track the size, location and nuisance of feral cat colonies. This issue concerns communities nationwide that hold some 70 to 100 million unhoused cats and kittens.

By the nuisance criteria, the traditional Trap-Neuter-Return (TNR) method that diminishes hormone production and mating behaviors wins hands down, over the Trap-Vasectomy-Hysterectomy-Return (TVHR) method that leaves hormone production intact, said Dr. Rachael Neilan, assistant professor of mathematics.

Like other researchers, student Timothy Ireland started with a mathematical model based on differential equations, then developed an even more complex, agent-based computational program. This program allows for detailed inputs, such as ages and locations of individual cats, environmental conditions, newly abandoned felines and the use of TNR or TVHR. Each cat in the model has its own identity and behaviors, and the program unfolds something like a video game for felines.

Because of his unique approach, Ireland presented his work at the Nov. 21 National Institute of Mathematical and Biological Synthesis undergraduate research symposium in Knoxville, Tenn. Ireland’s agent-based model, a cutting-edge technique in applied mathematics drew much interest and attention.

Ireland and Neilan worked closely with Dr. Becky Morrow, a veterinarian and assistant professor of biological sciences, and Dr. Lisa Ludvico, a DNA specialist and assistant professor of biological sciences, in the Bayer School of Natural and Environmental Sciences, who sought a scientific model for the most effective control strategies and provided the modelers with field-tested assumptions.

“You have to know the responses of feral cats to different environment cues—and how the cats interact with each other,” said Neilan, who received a Duquesne Faculty Development grant for the project. “The model is an elaborate computational and mathematical system built on biological assumptions and provides answers to important questions.”

The project started with community engagement as part of a class in differential equations. Students fed off the practical challenge of the project, Neilan said.

“This project illustrates the importance of studying math and how math can be used to solve a real-life problem,” Neilan said. “Students are excited to see their work result in something with practical meaning, especially when the results impact the local community.”