Feeding feedbacks: coupling human feeding of wildlife to observations of ecological processes shapes wildlife infection dynamics and impacts

Richard Hall

University of Georgia

"Feeding feedbacks: coupling human feeding of wildlife to observations of ecological processes shapes wildlife infection dynamics and impacts"

Humans provide food for wildlife for conservation and recreational purposes, but the resulting aggregation of wildlife around food sources can increase transmission of infectious diseases. Past work investigating the consequences of wildlife feeding for parasite transmission typically assumes that food is provided at a constant rate, but in reality, observations of changing wildlife abundance or infection can influence how much food is provided, potentially generating feedbacks between human behavior and wildlife disease. Focusing on backyard bird-feeding as a widespread and globally popular form of wildlife feeding, I develop a simple mathematical model for coupling the abundance and infection of birds with the intensity of food provisioning, contrasting scenarios where the rate of food provisioning is independent of, or depends on, components of the natural system. Unlike constant food provisioning, which usually results in a small outbreak followed by a smooth approach to equilibrium infection prevalence, coupling food provisioning to bird abundance and infection can result in more complex emergent dynamics, including larger and more frequent epidemic peaks and higher cumulative bird mortality. Accounting for this coupling of human activity to observations of ecological dynamics could inform development of best practice guidelines for wildlife feeding that minimize its unintended negative consequences.

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