House Wrens are very territorial during the summer months, often taking over multiple birdhouses and nests they find. Female House Wrens are especially picky about where they nest. If a nest does not meet their high standards, they will pick at it or even destroy it. If they find other birds' eggs in a nest or birdhouse, they destroy those as well. House Wrens also fill other birds' nests in their territory with sticks, making them unusable so that no other birds can live nearby. Females seem to take pleasure in destroying the work of other birds, all while hiding their behavior behind a cheerful song.