Department or Program



Lyme disease caused by Borrelia burgdorferi infection is the most common vector-borne illness in the United States, and has become increasingly reported since it was first described clinically. The tick species Ixodes scapularis is responsible for disease transmission between endothermic hosts. Consequently, the spatial patterns of human infection are positively correlated with population densities of the tick. Field observations have shown that migrating songbirds often carry ticks during the fall as they travel southward. However, no research currently predicts or demonstrates the magnitude of tick dispersal by fall migrants. The goal of this research was to develop an individual-based model of avian migration and bird-tick interactions to investigate species-specific patterns of I. scapularis dispersal within the continental United States by southward migrating songbirds. The model used in this research predicts the dispersal of over a million ticks outside of the current range of the species to most areas predicted to be climatically suitable for the tick, both presently and in the future. Out of areas without an established tick population, Eastern Minnesota, Iowa, Virginia and North Carolina experienced the highest level of tick detachment events, suggesting that birds may play a significant role in the range expansion of I. scapularis into these regions. This model suggests that the dispersal of I. scapularis by avian species is a critical factor in determining human infection risk to Lyme disease and other tick-borne pathogens in the United States. In the future, this model can be used as a virtual laboratory to analyze how local climate change patterns may impact the dispersal and range expansion of I. scapularis through changes to the phenological synchrony of ticks and songbirds.

Level of Access

Restricted: Embargoed [Open Access After Expiration]

First Advisor

Dearborn, Donald

Date of Graduation


Degree Name

Bachelor of Science

Number of Pages