Males and females of the hooded merganser form monogamous pairs and they remain together until the female has selected a nesting cavity and completed laying her clutch. After that, the male leaves the female to incubate and care for the brood. Females will actively seek out cavities in dead trees or artificial nest boxes such as those provided for nesting wood ducks. They prefer cavities 4–15 feet off the ground. Breeding occurs anytime between the end of February and the end of June, depending on the region.