The spread of infectious disease in wildlife represents an emerging threat to biodiversity. Particularly among predators, the effects of emerging infectious diseases not only include population declines and potential extirpation, but also can result in top-down effects on prey communities. In North America, several hibernating bat species face serious population declines due to the emergence of white-nose syndrome, a devastating disease caused by the fungal pathogen Pseudogymnoascus destructans. While arthropodivorous bats are often lauded for providing ecosystem services in the form of agricultural pest suppression, other regulatory effects on the arthropod food web as a whole have seldom been assessed. In light of the impending westward spread of white-nose syndrome and corresponding predicted bat population declines, this dissertation seeks to characterize the role of bats as top predators in the nocturnal arthropod food web and to assess the broader ecological consequences of disease-related bat population declines. Specifically, this research focuses on two common bat species, the little brown bat (Myotis lucifugus) and the big brown bat (Eptesicus fuscus), to explore the response of bats to changing prey abundance (Chapter 1), changes in bat foraging patterns over the past century (Chapter 2), top-down consequences of bat declines on arthropod communities (Chapter 3), and the possibility of the functional replacement of one bat species by another (Chapter 4). Overall, this dissertation demonstrates that the function of bats in the nocturnal arthropod food web is complex, and that declines among little brown bats in particular can have top-down effects which are unlikely to be ameliorated by other persisting bat species. As such, these results emphasize the necessity of promoting the conservation of bats and other aerial arthropodivores, while highlighting their importance as predators that influence their respective food webs.