A discrete-time bioeconomic model of free-roaming cat management: A case study in Knox County, Tennessee

Unowned free-roaming cats are a global problem due to predation on wildlife and the spread of infectious diseases. Programs such as Trap, Neuter, and Return (TNR) and Trap-Euthanize (TE) have been used to manage cat populations. We present a bioeconomic model using data from Knox County, Tennessee, U.S., and some parameters from literature that weighs benefits and costs of free-roaming cat management pro-grams. A benefit of a management program is the reduction in wildlife killed by free-roaming cats, illus-trated in the model by placing a value on wildlife. The economic management costs include the costs of trapping and neutering, and the procedural and emotional costs of euthanasia. We highlight two key factors that determine which management strategy is most cost effective. The first is whether cat caretakers cooperate with management by decreasing food available for cat groups. The second is the value attributed to saving the lives of wildlife and free-roaming cats. Based on plausible cat and wildlife values, TNR was the most cost effective when caretakers cooperated, but TE was the most cost-effective when caretakers did not cooperate. When the model is adjusted for the local goals, effort, and information, it can be used as a tool for management.

Automated summary

The benefits and costs of managing unowned free-roaming cats can be evaluated using a bioeconomic model, with key factors being the cooperation of cat caretakers and the value placed on wildlife and free-roaming cat lives. Adjusting the model based on specific goals and information can make it a useful management tool.