Mallards nest on the ground on dry land that is close to water; nests are generally concealed under overhanging grass or other vegetation. Occasionally, Mallards nest in agricultural fields, especially alfalfa but also winter wheat, barley, flax, and oats.

How do you tell if a duck is nesting?

Most ducks lay eggs very early in the morning, so you probably won't notice her heading for her nest box. You can tell if a duck is laying by feeling her pelvic bones as you hold her. A duck's pelvic bones spread and become flexible when she is capable of laying eggs.

Do Mallards sit on their eggs?

Once incubation begins, the Mallard will sit on her eggs for most of the day, for about 25-29 days. She will leave the eggs (typically covered in down) for an hour or so each morning and afternoon so that she can feed.