By now many mallard nests are underway. Some delay nesting until well into summer, but normally only one set of eggs is laid each year. Mallards nest by choice in city parks, in school courtyards, or under shrubs close to the entrances to our homes. Occasionally nests are built in forks of trees or on abandoned hawk nests, sometimes as high as 25 feet from the ground. However, nests are usually built on dry ground among dead grasses and other plants at the edges of marshes, ponds and lakes. The nest itself is most often a hollow in the ground, well concealed, built with grasses and leaves or any convenient material from the immediate vicinity, and lined with down from the breast of the female.

Normally eight to 12 eggs are laid, one per day. The eggs are light greenish to nearly white. The incubation is done by the female alone with the eggs usually hatching in 26 days. Incubation starts with the laying of the last egg so that all the eggs will hatch on the same day. The drakes usually take no interest in family cares after the eggs are laid, but gather in small flocks by themselves, molt into eclipse plumage and hide among the plants in wetlands where they spend the summer. Ducklings, like goslings, are precocial. As soon as their down dries after hatching the solitary mother leads them to water. There she teaches her young to find food and to stay close to her for protection.