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Ecological networks are known to influence ecosystem attributes, but we poorly understand how interspecific network structure affect population demography of multiple species, particularly for vertebrates. Establishing the link between network structure and demography is at the crux of being able to use networks to understand population dynamics and to inform conservation.We addressed the critical but unanswered question, does network structure explain demographic consequences of urbanization?We studied 141 ecological networks representing interactions between plants and nesting birds in forests across an urbanization gradient in Ohio, USA from 2001-2011. Nest predators were identified by video-recording nests and surveyed from 2004-2011.As landscapes urbanized, bird-plant networks were more nested, less compartmentalized, and dominated by strong interactions between a few species (i.e., low evenness). Evenness of interaction strengths promoted avian nest survival, and evenness explained demography better than urbanization, level of invasion, numbers of predators, or other qualitative network metrics. Highly uneven networks had approximately half the nesting success as the most even networks. Thus, nest survival reflected how urbanization altered species interactions, particularly with respect to how nest placement affected search efficiency of predators.The demographic effects of urbanization were not direct, but were filtered through bird-plant networks. This study illustrates how network structure can influence demography at the community level, and further, that knowledge of species interactions and a network approach may be requisite to understanding demographic responses to environmental change.This article is protected by copyright. All rights reserved.