The primary objective of the past field season with support from Nuttal was to explain the mechanisms responsible for Canada warbler reproductive success, and the pattern of that success over years, among age classes, and at several spatial scales. We are measuring reproductive success at the level of individuals in the context of populations. We consider the habitat features and behavioral milieu that best promote successful fledging. We characterize the behaviors most associated with success, such as neighborhood dynamics, male and female mating opportunism, individual attributes – including age, plumage and physiological condition measured by carotenoid concentrations and reflectance values in feathers – that increase success. We examine whether “hot” areas occur within neighborhoods based upon asymmetries in paternity among males in each neighborhood, and whether males and females shift territories or choices for extra-pair copulations, respectively, recognizing these hot spots.